Type 2 Diabetes
Supplements studied for type 2 type-2-diabetes.
Overview
Several supplements show medium-level evidence for blood sugar effects in type 2 type-2-diabetes. L-Carnitine (25 studies) may slightly lower blood sugar, insulin, and improve insulin sensitivity at doses of at least 2 g daily for three months or more. Resveratrol (24 studies) may improve blood sugar and insulin resistance, especially at 250 mg or more daily in poorly controlled type-2-diabetes. Magnesium (21 studies) supplementation may help when intake is low, and dietary magnesium is linked to better glucose control.
Curcumin (9 studies) may modestly lower fasting blood sugar and HbA1c in some trials, though quality varies. Panax Ginseng (8 studies) shows mixed results, with small fasting glucose improvements in some studies but little change in HbA1c. See the heatmap and evidence reviews below for evidence across 25 supplements.
Effect graph
Relevant supplements
Relevant supplements sorted by DEX Score.
| Beta-Glucan | ★★★★★ | High |
| Zinc | ★★★★★ | Medium |
| Taurine | ★★★★★ | Medium |
| Panax Ginseng | ★★★★★ | Medium |
| Nattokinase | ★★★★★ | Medium |
| Milk Thistle | ★★★★★ | Medium |
| Jiaogulan | ★★★★★ | Medium |
| Inulin | ★★★★★ | Medium |
| Garlic | ★★★★★ | Medium |
| Flaxseed | ★★★★★ | Medium |
| Curcumin | ★★★★★ | Medium |
| Apple Cider Vinegar | ★★★★★ | Medium |
| Resveratrol | ★★★★★ | Medium |
| Olive Oil | ★★★★★ | Medium |
| Oats | ★★★★★ | Medium |
| Magnesium | ★★★★★ | Medium |
| L-Carnitine | ★★★★★ | Medium |
| Chromium | ★★★★★ | Medium |
| Cassia Cinnamon | ★★★★★ | Medium |
| Caffeine | ★★★★★ | Medium |
| Berberine | ★★★★★ | Medium |
| Probiotics | ★★★★★ | Medium |
| Beta-Alanine | ★★★★★ | Medium |
| Ivy Gourd | ★★★★★ | Medium |
| Yerba Mate | ★★★★★ | Medium |
| Vitamin D | ★★★★★ | Low |
| Green Tea | ★★★★★ | Low |
| Aloe | ★★★★★ | Low |
| Vitamin K | ★★★★★ | Low |
| Vitamin B9 (Folate) | ★★★★★ | Low |
| Melatonin | ★★★★★ | Low |
| Lycopene | ★★★★★ | Low |
| Lutein | ★★★★★ | Low |
| Kefir | ★★★★★ | Low |
| Ginger | ★★★★★ | Low |
| Flaxseed Oil | ★★★★★ | Low |
| Cocoa | ★★★★★ | Low |
| Biotin | ★★★★★ | Low |
| Astragalus | ★★★★★ | Low |
| Alpha-Lipoic Acid | ★★★★★ | Low |
| Quercetin | ★★★★★ | Low |
| Potassium | ★★★★★ | Low |
| Ginkgo | ★★★★★ | Low |
| Boswellia | ★★★★★ | Low |
| American Ginseng | ★★★★★ | Low |
| Whey Protein | ★★★★★ | Low |
| Red Yeast Rice | ★★★★★ | Low |
| L-Citrulline | ★★★★★ | Low |
| Kudzu | ★★★★★ | Low |
| Kombucha | ★★★★★ | Low |
| Fish Oil | ★★★★★ | Very Low / None |
| Eleuthero | ★★★★★ | Low |
| Casein Protein | ★★★★★ | Low |
| Bilberry | ★★★★★ | Low |
| Astaxanthin | ★★★★★ | Low |
| Zeaxanthin | ★★★★★ | Very Low / None |
| Selenium | ★★★★★ | Very Low / None |
| Lysine | ★★★★★ | Low |
| Ceylon Cinnamon | ★★★★★ | Very Low / None |
| Branched Chain Amino Acids (BCAAs) | ★★★★★ | Very Low / None |
| Ashwagandha | ★★★★★ | Low |
| Reishi | ★★★★★ | Very Low / None |
| Iron | ★★★★★ | Very Low / None |
| Oleic Acid | ★★★★★ | Very Low / None |
| Black Tea | ★★★★★ | Very Low / None |
| Acetyl-L-Carnitine | ★★★★★ | Very Low / None |
Studies
Find individual evidence reviews for supplements sorted by DEX Score.
66 supplements for , and rated at least stars. All purchase bands. No minimum star filter.
Beta-GlucanView supplement →
Consider purchase·★★★★★
How we scored this▸
- Beta-glucans, a type of fiber found in oats and barley, can help people with type 2 diabetes control their blood sugar, especially after meals.
- Eating foods with about 3 grams of beta-glucans daily for a few weeks to several months has been shown in studies to improve blood sugar levels and cholesterol.
- Beta-glucans work by slowing digestion and supporting gut health.
- Some studies have not found benefits, which may be due to different types or amounts used.
- For people with type 1 diabetes, evidence is more limited; beta-glucan snacks at bedtime may help reduce low blood sugar in the early part of the night in some cases, but overall results are mixed.
Browse 9 studies·2 meta-analyses
MetaThe effect of oat β-glucan on postprandial blood glucose and insulin responses: a systematic review and meta-analysis2021n=538
A meta-analysis of 103 trial comparisons (538 participants) found oat beta-glucan reduced postprandial glucose iAUC by 23% and insulin iAUC by 22%, with larger effects at higher dose and molecular weight >300 kg/mol.
- Effect
- Benefit
- Participants
- 538
RCTEffect of High β-glucan Barley on Postprandial Blood Glucose and Insulin Levels in Type 2 Diabetic Patients2020n=10
In 10 type 2 diabetic patients, a meal with 50% high beta-glucan barley mixed with white rice significantly lowered postprandial glucose and C-peptide iAUC versus white rice alone.
- Effect
- Benefit
- Dose
- 7.2 g/day
- Population
- Diabetic patients
- Participants
- 10
- Avg age
- ~52
Clinical trialThe effect of beta-glucan supplementation on glycemic control and variability in adolescents with type 1 diabetes mellitus2020n=30
In 30 adolescents with type 1 diabetes, 6 g/day oat beta-glucan for 1 week lowered mean, premeal/postmeal, and peak glucose and reduced glycemic variability (SD, CV, LBGI, CONGA) versus lower doses.
- Effect
- Benefit
- Duration
- 1 week
- Dose
- 3 g/day
- Population
- Children/adolescents
- Participants
- 30
RCTA Multifunctional Bread Rich in Beta Glucans and Low in Starch Improves Metabolic Control in Type 2 Diabetes: A Controlled Trial2017
In matched type 2 diabetic patients, ~6 months of beta-glucan-rich, low-starch functional bread reduced HbA1c by ~0.5–0.6% versus regular white bread and lowered postprandial and mean glucose.
- Effect
- Benefit
- Dose
- 7 g/day
- Population
- Diabetic patients
- Ages
- 50–80
RCTEffect of Oral Pre-Meal Administration of Betaglucans on Glycaemic Control and Variability in Subjects with Type 1 Diabetes2017n=14
In 14 adults with type 1 diabetes, 4.59 g/day oat beta-glucan before meals for 2 weeks did not improve glycemic control or variability versus placebo in this pilot crossover study.
- Effect
- No Benefit
- Duration
- 14 days
- Dose
- 4.59 g/day
- Population
- Adults
- Participants
- 14
MetaEffect of Oat β-Glucan Intake on Glycaemic Control and Insulin Sensitivity of Diabetic Patients: A Meta-Analysis of Randomized Controlled Trials2016
A meta-analysis of 4 RCTs (350 type 2 diabetic patients) found 2.5–3.5 g/day oat beta-glucan for 3–8 weeks lowered fasting glucose by 0.52 mmol/L and HbA1c by 0.21% versus control.
- Effect
- Benefit
- Duration
- 3–8 weeks
- Dose
- 3.5 g/day
- Population
- Diabetic patients
RCTA controlled study of consumption of beta-glucan-enriched soups for 2 months by type 2 diabetic free-living subjects2010
In 53 type 2 diabetic adults, 3.5 g/day beta-glucan in soup for 8 weeks significantly lowered triglycerides versus control but did not change total cholesterol, LDL, HDL, HbA1c, or fasting glucose.
- Effect
- No Benefit
- Duration
- 2 months
- Dose
- 3.5 g/day
- Population
- Diabetic patients
RCTThe consumption of bread enriched with betaglucan reduces LDL-cholesterol and improves insulin resistance in patients with type 2 diabetes2009n=46
In 46 type 2 diabetic patients, 3 weeks of beta-glucan-enriched bread (3 g/day) lowered LDL cholesterol by 0.66 mmol/L (16%), total cholesterol by 0.80 mmol/L, fasting insulin, and HOMA-IR versus control bread.
- Effect
- Benefit
- Duration
- 3 weeks
- Dose
- 3 g/day
- Population
- Diabetic patients
- Participants
- 46
Influence of a beta-glucan-enriched bedtime snack on nocturnal blood glucose levels in diabetic children2001n=38
In 38 children with diabetes, a beta-glucan-enriched bedtime snack flattened the pre-midnight glucose curve but did not reduce the 27% prevalence of hypoglycemia at 2 AM versus a conventional snack.
- Effect
- No Benefit
- Population
- Children/adolescents
- Participants
- 38
Apple Cider VinegarView supplement →
Consider purchase·★★★★★
How we scored this▸
- Apple cider vinegar may help lower blood sugar and cholesterol modestly in people with type 2 diabetes, but the evidence is mixed and many studies are small or of a low quality.
- Drinking about 1 to 2 tablespoons daily diluted in water might reduce fasting blood sugar and HbA1c levels slightly.
- Liquid vinegar may work better than pills.
- Side effects can include stomach upset, low potassium, and damage to tooth enamel if taken undiluted or in large amounts.
- People with diabetes should talk to a doctor before using ACV, especially if they take blood sugar medicines.
Browse 7 studies·3 meta-analyses
Systematic reviewEffects of apple cider vinegar on glycemic control and insulin sensitivity in patients with type 2 diabetes: A GRADE-assessed systematic review and dose-response meta-analysis of controlled clinical trials2025
A meta-analysis of 7 controlled trials found apple cider vinegar significantly lowered fasting blood sugar, HbA1c, and raised insulin in type 2 diabetes patients.
- Effect
- Benefit
- Population
- Diabetic patients
MetaThe Effects of Apple Cider Vinegar on Cardiometabolic Risk Factors: A Systematic Review and Meta-analysis of Clinical Trials2023n=1,320
A meta-analysis of 25 trials (1320 adults) found apple cider vinegar significantly reduced fasting glucose, HbA1c, and total cholesterol, with stronger effects in diabetic patients and at ≥12 weeks for triglycerides.
- Effect
- Benefit
- Population
- Adults
- Participants
- 1,320
RCTThe improvement effect of apple cider vinegar as a functional food on anthropometric indices, blood glucose and lipid profile in diabetic patients: a randomized controlled clinical trial2023n=72
In 72 type 2 diabetes patients over 8 weeks, 30 mL/day apple cider vinegar plus diet advice lowered fasting glucose, HbA1c, LDL, and cholesterol ratios versus diet alone.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 30 mL/day apple cider vinegar
- Population
- Adults
- Participants
- 72
MetaThe effect of apple cider vinegar on lipid profiles and glycemic parameters: a systematic review and meta-analysis of randomized clinical trials2021
A meta-analysis of 9 trials found apple cider vinegar significantly lowered total cholesterol, fasting glucose, and HbA1c; LDL, HDL, insulin, and HOMA-IR were unchanged overall.
- Effect
- Benefit
- Population
- Healthy adults
RCTCommercial Vinegar Tablets Do Not Display the Same Physiological Benefits for Managing Postprandial Glucose Concentrations as Liquid Vinegar2020n=10
In 12 healthy young adults, liquid vinegar 1.25 g acetic acid before a meal reduced 60-minute glucose excursion 31% versus placebo, while whole vinegar tablets did not.
- Effect
- Benefit
- Dose
- 1.50 g acetic acid
- Population
- Adults
- Participants
- 10
- Ages
- 18–35
RCTThe effect of apple vinegar consumption on glycemic indices, blood pressure, oxidative stress, and homocysteine in patients with type 2 diabetes and dyslipidemia: A randomized controlled clinical trial2019n=70
In 70 type 2 diabetes patients with dyslipidemia, 20 mL/day apple vinegar for 8 weeks improved fasting glucose and antioxidant capacity (DPPH) versus control, without blood pressure or homocysteine changes.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 20 ml/day
- Population
- Diabetic patients
- Participants
- 70
CrossoverVinegar improves insulin sensitivity to a high-carbohydrate meal in subjects with insulin resistance or type 2 diabetes2004
A crossover study title indicates vinegar improved insulin sensitivity after a high-carbohydrate meal in insulin-resistant and type 2 diabetic subjects; the available abstract contains no outcome data.
- Effect
- Benefit
CurcuminView supplement →
Consider purchase·★★★★★
How we scored this▸
- Some lower quality studies suggest that taking curcumin, a component of turmeric, may help improve blood sugar control in people with diabetes.
- In some small studies, curcumin lowered fasting blood sugar by about 8 mg/dL and, in one trial with a special curcumin form, by about 20 mg/dL after several months.
- Other reviews of studies showed curcumin can lower blood sugar and HbA1c (a long-term blood sugar measure) slightly more than placebo or usual treatment, though results varied widely.
- Some studies found no benefit.
- Overall, the evidence is mixed, and the amount of curcumin taken varied a lot between studies.
Browse 9 studies·5 meta-analyses
MetaComparative effectiveness of six herbs in the management of glycemic status of type 2 diabetes mellitus patients: A systematic review and network meta-analysis of randomized controlled trials2023n=3,130
A network meta-analysis of 44 RCTs (3,130 adults with type 2 diabetes) found curcumin significantly reduced fasting blood glucose (SMD −13.15) versus placebo, though it was not among the most effective herbs for HbA1c.
- Effect
- Benefit
- Population
- Adults
- Participants
- 3,130
MetaTurmeric and curcuminiods ameliorate disorders of glycometabolism among subjects with metabolic diseases: A systematic review and meta-analysis of randomized controlled trials2022
A meta-analysis of 17 RCTs in metabolic disease found turmeric/curcuminoids lowered fasting blood glucose by 7.86 mg/dL, HbA1c by 0.38%, and HOMA-IR by 1.01 compared with controls.
- Effect
- Benefit
- Duration
- 12 weeks
- Population
- Healthy adults
RCTEffect of Curcumin on Diabetic Kidney Disease: A Systematic Review and Meta-Analysis of Randomized, Double-Blind, Placebo-Controlled Clinical Trials2021n=290
A meta-analysis of 5 double-blind RCTs (290 diabetic kidney disease patients) found curcumin improved serum creatinine, total cholesterol, systolic blood pressure, and fasting blood glucose versus placebo.
- Effect
- Benefit
- Participants
- 290
RCTEfficacy and Safety of Curcumin Supplement on Improvement of Insulin Resistance in People with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2021n=453
A meta-analysis of 4 RCTs (453 type 2 diabetes patients) found curcumin reduced HOMA-IR and improved glycemic control and triglycerides in Asian populations, though Middle Eastern subgroup results were inconsistent.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 453
MetaPotential Therapeutic Effects of Curcumin on Glycemic and Lipid Profile in Uncomplicated Type 2 Diabetes-A Meta-Analysis of Randomized Controlled Trial2021
A meta-analysis in uncomplicated type 2 diabetes found curcumin significantly reduced HbA1c, HOMA-IR, and LDL cholesterol versus control, though fasting glucose itself did not reach statistical significance.
- Effect
- Benefit
- Population
- Patients with type 2 diabetes
RCTThe Effects of Nano-curcumin on Metabolic Status in Patients With Diabetes on Hemodialysis, a Randomized, Double Blind, Placebo-controlled Trial2020n=30
In 60 diabetic patients on hemodialysis, 80 mg/day nano-curcumin for 12 weeks significantly lowered fasting glucose, insulin, lipids, hs-CRP, and oxidative stress markers versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 80 mg/day
- Population
- Diabetic patients
- Participants
- 30
RCTEffects of Curcuminoids Plus Piperine on Glycemic, Hepatic and Inflammatory Biomarkers in Patients with Type 2 Diabetes Mellitus: A Randomized Double-Blind Placebo-Controlled Trial2018n=100
A 3-month study including 100 type 2 diabetics (18-65 yrs) found 500 mg/day curcumin + 5 mg/day piperine significantly reduced serum levels of glucose (-9±16 mg/dL vs. -3±11 mg/dL), C-peptide (-0.6±0.8 ng/mL vs. 0.02±0.6 ng/mL) and HbA1c (0.9±1.1% vs. -0.2±0.5%) vs. placebo. There was also a reduction in serum alanine aminotransferase (-2±6 vs. -1±5) and aspartate aminotransferase (-3±5 vs. -0.3±4). No significant differences were observed in hs-CRP concentrations in T2D patients. [10240]
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 500 mg/day
- Population
- Diabetic patients
- Participants
- 100
- Ages
- 18–65
RCTThe effect of nano-curcumin on HbA1c, fasting blood glucose, and lipid profile in diabetic subjects: a randomized clinical trial2016
In 70 type 2 diabetes patients (ages 18–65), 80 mg/day nano-curcumin for 3 months significantly reduced HbA1c, fasting blood glucose, triglycerides, LDL cholesterol, and BMI versus placebo.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 80 mg/day
- Population
- Diabetic patients
- Ages
- 18–65
RCTCurcuminoids exert glucose-lowering effect in type 2 diabetes by decreasing serum free fatty acids: a double-blind, placebo-controlled trial2012n=100
A 3-month study of 100 type 2 diabetics found that curcuminoids (300 mg/day) significantly decreased fasting blood glucose, HbA1c and insulin resistance index compared to placebo. The curcuminoids group also experienced an increase in lipoprotein lipase activity and a significant decrease in serum total free fatty acids and triglycerides. [10242]
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 300 mg/day
- Population
- Diabetic patients
- Participants
- 100
FlaxseedView supplement →
Consider purchase·★★★★★
How we scored this▸
- Ground flaxseed may help lower blood sugar and insulin levels in people with diabetes or prediabetes, although results from studies are mixed.
- Some research shows that taking 13–40 grams daily for several weeks can modestly improve blood sugar control, but other studies find little to no effect.
- Whole flaxseed seems to have less clear benefits, and flaxseed supplements focused on lignans have not consistently lowered blood sugar or HbA1c.
- Overall, flaxseed may provide small improvements, but the evidence is not strong or consistent.
Browse 8 studies·4 meta-analyses
MetaEffects of flaxseed supplementation on weight loss, lipid profiles, glucose, and high-sensitivity C-reactive protein in patients with coronary artery disease: A systematic review and meta-analysis of randomized controlled trials2024
A meta-analysis of 6 RCTs in coronary artery disease patients found flaxseed supplementation did not significantly change weight, lipids, hs-CRP, or glucose.
- Effect
- No Benefit
- Population
- CAD patients
MetaFlaxseed supplementation significantly reduces hemoglobin A1c in patients with type 2 diabetes mellitus: A systematic review and meta-analysis2023
A meta-analysis of 13 T2DM trials found flaxseed supplementation significantly lowered HbA1c versus control, without consistent effects on weight, blood pressure, fasting glucose, or lipids overall.
- Effect
- Benefit
- Population
- Adults
MetaEffect of flaxseed (Linum usitatissimum) supplementation on glycemic control and insulin resistance in prediabetes and type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials2022
A meta-analysis of RCTs found flaxseed supplementation modestly reduced fasting glucose, HbA1c, and HOMA-IR in people with prediabetes or type 2 diabetes.
- Effect
- Benefit
RCTEffect of flaxseed or psyllium vs. placebo on management of constipation, weight, glycemia, and lipids: A randomized trial in constipated patients with type 2 diabetes2018
In a 12-week single-blind RCT of 77 constipated type 2 diabetes patients, cookies containing 20 g/day flaxseed or psyllium improved constipation symptoms versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 20 g/day
- Population
- Adults
MetaFlaxseed supplementation on glucose control and insulin sensitivity: a systematic review and meta-analysis of 25 randomized, placebo-controlled trials2018
A meta-analysis of 25 flaxseed RCTs found supplementation significantly reduced fasting glucose (−2.94 mg/dL), insulin, and HOMA-IR and increased insulin sensitivity, without significant HbA1c change.
- Effect
- Benefit
RCTDaily flaxseed consumption improves glycemic control in obese men and women with pre-diabetes: a randomized study2013n=25
In a crossover RCT of 25 overweight adults with prediabetes, 13 g/day ground flaxseed for 12 weeks reduced fasting glucose and insulin versus 0 g, while 26 g/day did not differ from placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 13–26 g/day
- Population
- Adults
- Participants
- 25
RCTFlaxseed supplementation improved insulin resistance in obese glucose intolerant people: a randomized crossover design2011
In a crossover RCT of 9 obese glucose-intolerant adults, 40 g/day flaxseed for 12 weeks reduced lipid peroxidation (TBARS) and HOMA-IR versus wheat bran, without changing inflammatory cytokines.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 40 g/day
- Population
- Adults
RCTEffects of a flaxseed-derived lignan supplement in type 2 diabetic patients: a randomized, double-blind, cross-over trial2007
In a 12-week crossover RCT of 68 Chinese type 2 diabetic patients (ages 50–79), 360 mg/day flaxseed lignan produced modest but statistically significant improvements in glycemic control versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 360 mg/day
- Population
- Diabetic patients
- Ages
- 50–79
GarlicView supplement →
Consider purchase·★★★★★
How we scored this▸
- Most research suggests that taking garlic supplements for at least 12 weeks can slightly lower fasting blood sugar in people with diabetes.
- Garlic powder, garlic oil, or aged garlic extract have been shown to reduce fasting glucose by a small amount, especially in people with higher blood sugar at the start.
- Taking garlic along with diabetes medicine like metformin may improve blood sugar control more than medicine alone.
- However, it isn’t clear if garlic helps control blood sugar after meals or long-term blood sugar levels (HbA1c).
- Older studies didn’t find clear benefits, but newer research is more supportive.
- One study found that taking aged garlic extract for a year didn’t improve heart muscle changes related to diabetes.
Browse 5 studies·1 meta-analysis
RCTAged garlic extract reduces left ventricular myocardial mass in patients with diabetes: A prospective randomized controlled double-blind study2020n=65
In a 52-week double-blind RCT of 65 diabetic patients (mean age ~58), 2,400 mg/day aged garlic extract reduced left ventricular myocardial mass on cardiac CT versus placebo.
- Effect
- Benefit
- Duration
- 52 weeks
- Dose
- 400 mg/day
- Population
- Diabetic patients
- Participants
- 65
- Avg age
- ~58
MetaGarlic intake lowers fasting blood glucose: meta-analysis of randomized controlled trials2015n=513
A meta-analysis of 7 RCTs (513 subjects) found garlic intake significantly lowered fasting blood glucose in people with and without diabetes.
- Effect
- Benefit
- Participants
- 513
RCTGarlic (Allium sativum) supplementation with standard antidiabetic agent provides better diabetic control in type 2 diabetes patients2011n=60
In a 24-week double-blind RCT of 60 type 2 diabetic patients on metformin, adding 300 mg garlic tablets three times daily improved fasting glucose and lipids versus placebo plus metformin.
- Effect
- Benefit
- Duration
- 24 weeks
- Dose
- 300 mg 3×/day
- Population
- Diabetic patients
- Participants
- 60
RCTMetabolic effects of time-released garlic powder tablets in type 2 diabetes mellitus: the results of double-blinded placebo-controlled study2008
In a 4-week double-blind RCT of 60 type 2 diabetic patients, time-released garlic powder (Allicor) improved metabolic control and plasma lipids versus placebo.
- Effect
- Benefit
- Duration
- 4 weeks
- Population
- Diabetic patients
RCTGarlic shows promise for improving some cardiovascular risk factors2001
A systematic review of 45 randomized garlic trials lasting at least 4 weeks found modest improvements in some cardiovascular risk factors, though effects varied by garlic preparation and outcome measured.
- Effect
- Benefit
InulinView supplement →
Consider purchase·★★★★★
How we scored this▸
- Taking inulin supplements along with diabetes medication may help improve blood sugar control in people with type 2 diabetes, especially when taken for a short time (6–12 weeks).
- Studies show that inulin can lower blood sugar and a measure of long-term blood sugar control (HbA1c).
- Women taking diabetes medicines who took 10 grams of inulin daily for 8 weeks saw improvements.
- Eating more inulin-rich foods over several years may also lower the risk of developing diabetes.
- Some studies using inulin with other supplements found benefits on blood sugar, weight, and blood pressure, but others did not.
Browse 7 studies·3 meta-analyses
ObservationalInulin intake and the incidence of cardiometabolic diseases: a prospective cohort study2022
A prospective cohort study examined whether habitual dietary inulin intake is associated with incidence of cardiometabolic diseases in adults.
- Effect
- No Benefit
- Dose
- 100 g/day
- Population
- Adults
RCTEffect of inulin-type fructans on appetite in patients with type 2 diabetes: a randomised controlled crossover trial2021n=12
In 12 adults with type 2 diabetes over 6 weeks, inulin-type fructans (16 g/day) improved appetite regulation and reduced hunger versus maltodextrin.
- Effect
- Benefit
- Duration
- 6 weeks
- Dose
- 16 g/day
- Population
- Adults
- Participants
- 12
RCTEfficacy of inulin supplementation in improving insulin control, HbA1c and HOMA-IR in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials2020n=661
A meta-analysis of RCTs (661 type 2 diabetes patients) found inulin significantly improved HbA1c, insulin control, and HOMA-IR versus control.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 661
MetaEffect of Inulin-Type Carbohydrates on Insulin Resistance in Patients with Type 2 Diabetes and Obesity: A Systematic Review and Meta-Analysis2019
A meta-analysis found inulin-type carbohydrates reduced insulin resistance and improved metabolic markers in type 2 diabetes and obesity.
- Effect
- Benefit
- Population
- Diabetic patients
MetaInulin-type fructans supplementation improves glycemic control for the prediabetes and type 2 diabetes populations: results from a GRADE-assessed systematic review and dose-response meta-analysis of 33 randomized controlled trials2019n=1,346
A GRADE-assessed meta-analysis (1,346 participants) found inulin-type fructans (~10 g/day) improved glycemic control in prediabetes and type 2 diabetes.
- Effect
- Benefit
- Dose
- 10 g/day
- Participants
- 1,346
RCTMilk Powder Co-Supplemented with Inulin and Resistant Dextrin Improves Glycemic Control and Insulin Resistance in Elderly Type 2 Diabetes Mellitus: A 12-Week Randomized, Double-Blind, Placebo-Controlled Trial2018
In elderly type 2 diabetes patients over 12 weeks, milk powder with inulin and resistant dextrin improved fasting glucose and insulin sensitivity versus plain milk powder.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 45 g/day
- Population
- Older adults
RCTInulin controls inflammation and metabolic endotoxemia in women with type 2 diabetes mellitus: a randomized-controlled clinical trial2014n=49
In 49 women with type 2 diabetes over 8 weeks, inulin (10 g/day) reduced inflammatory markers and metabolic endotoxemia versus maltodextrin.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 10 g/day
- Population
- Women
- Participants
- 49
JiaogulanView supplement →
Consider purchase·★★★★★
How we scored this▸
- Jiaogulan (also called Gynostemma) may help with blood sugar control in people recently diagnosed with type 2 diabetes.
- In clinical studies from Vietnam, adults who took jiaogulan whole plant extract powder (1.5 grams in water, twice a day before meals) for 8 to 12 weeks lowered their average blood sugar (HbA1c) by about 1% and saw drops in fasting blood sugar and after-meal blood sugar compared with people taking green tea.
- Some participants were also taking a diabetes medication called a sulfonylurea, while others were not on any medications.
- In another small short-term study, the same jiaogulan treatment improved blood sugar and insulin sensitivity after 4 weeks, but the benefits faded when participants switched to placebo.
- All of these studies were small and done by the same research team, so the results should be interpreted with caution.
Browse 4 studies·1 meta-analysis
Systematic reviewEffectiveness and Safety of Ayurvedic Medicines in Type 2 Diabetes Mellitus Management: A Systematic Review and Meta-Analysis2022n=21,191
A systematic review of 199 Ayurvedic medicine RCTs (21,191 participants) found Boswellia serrata reduced HbA1c by 0.5% (95% CI −0.7 to −0.4) compared with control in type 2 diabetes.
- Effect
- Benefit
- Population
- Adults
- Participants
- 21,191
Gynostemma pentaphyllum Tea Improves Insulin Sensitivity in Type 2 Diabetic Patients2013
In drug-naïve type 2 diabetes patients, Gynostemma pentaphyllum tea 6 g/day for 4 weeks improved insulin sensitivity on somatostatin-insulin-glucose testing and lowered fasting glucose versus placebo.
- Effect
- Benefit
- Duration
- 4 weeks
- Dose
- 6 g/day
- Population
- Diabetic patients
RCTAntidiabetic Effects of Add-On Gynostemma pentaphyllum Extract Therapy with Sulfonylureas in Type 2 Diabetic Patients2012
In type 2 diabetes patients on gliclazide, adding Gynostemma pentaphyllum extract 6 g/day for 8 weeks further lowered fasting glucose and HbA1c by about 2% versus placebo add-on.
- Effect
- Benefit
- Duration
- 4 weeks
- Dose
- 6 g/day
- Population
- Diabetic patients
RCTAntidiabetic effect of Gynostemma pentaphyllum tea in randomly assigned type 2 diabetic patients2010
In 24 drug-naïve type 2 diabetes patients, Gynostemma pentaphyllum tea 6 g/day for 12 weeks lowered fasting glucose by 3.0 mmol/L versus 0.6 mmol/L with placebo (p<0.01) and reduced HbA1c by about 2%.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 6 g/day
- Population
- Diabetic patients
Milk ThistleView supplement →
Consider purchase·★★★★★
How we scored this▸
- Milk thistle extracts may help improve blood sugar control in people with diabetes. Research combining many studies shows that milk thistle can lower fasting blood sugar by about 22 mg/dL, reduce long-term blood sugar control (HbA1c) by 0.85%, and lower fasting insulin levels. Most studies were done in the Middle East, so it’s unclear if the same benefits apply everywhere.
- In people with type 2 diabetes, taking milk thistle (210-600 mg daily) alone or with other natural ingredients for up to 6 months can help lower blood sugar and HbA1c. The benefits may be stronger in shorter studies and when combined with other ingredients.
- Some combination products, like Berberol from Italy, which contains milk thistle and turmeric extracts, have shown benefits for blood sugar control in people with type 2 diabetes, obesity, metabolic syndrome, and type 1 diabetes.
Browse 8 studies·2 meta-analyses
MetaImpacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose-Response Meta-Analysis2024n=1,943
A dose-response meta-analysis of 33 trials (1,943 participants) found silymarin supplementation reduced fasting glucose, total cholesterol, triglycerides, LDL cholesterol, and diastolic blood pressure.
- Effect
- Benefit
- Population
- Adults
- Participants
- 1,943
MetaThe therapeutic effects of silymarin for patients with glucose/lipid metabolic dysfunction: A meta-analysis2020n=1,358
A meta-analysis of 16 studies (1,358 patients) found silymarin significantly improved fasting glucose, HbA1c, insulin resistance, and lipid profiles in glucose/lipid metabolic dysfunction.
- Effect
- Benefit
- Population
- Patients with glucose/lipid metabolic dysfunction
- Participants
- 1,358
RCTLower glycemic indices and lipid profile among type 2 diabetes mellitus patients who received novel dose of Silybum marianum (L.) Gaertn. (silymarin) extract supplement: A Triple-blinded randomized controlled clinical trial2018n=20
An RCT of 40 type 2 diabetes patients found silymarin 140 mg three times daily for 45 days reduced fasting glucose, insulin, HOMA-IR, and triglycerides and increased HDL cholesterol vs placebo.
- Effect
- Benefit
- Duration
- 45 days
- Dose
- 140 mg/day
- Population
- Diabetic patients
- Participants
- 20
- Ages
- 25–50
RCTBioimpedance analysis, metabolic effects and safety of the association Berberis aristata/Bilybum marianum: a 52-week double-blind, placebo-controlled study in obese patients with type 2 diabetes2017n=136
A 52-week RCT of 136 obese type 2 diabetes patients found berberine plus silymarin improved glycemic control, lipids, abdominal fat, and cardiovascular risk score vs placebo.
- Effect
- Benefit
- Duration
- 52 weeks
- Population
- Diabetic patients
- Participants
- 136
RCTThe role of a fixed Berberis aristata/Silybum marianum combination in the treatment of type 1 diabetes mellitus2016
An RCT of 85 type 1 diabetes patients found berberine plus silymarin for 6 months reduced total insulin dose and improved HbA1c, fasting glucose, and lipid profile vs placebo.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 588/105 mg twice daily
- Population
- Diabetic patients
Pilot study on the additive effects of berberine and oral type 2 diabetes agents for patients with suboptimal glycemic control2012n=20
A pilot study of 20 type 2 diabetes patients with suboptimal glycemic control found berberine plus silymarin for 90 days improved HbA1c, insulin resistance, and lipid levels.
- Effect
- Benefit
- Duration
- 90 days
- Population
- Pregnant women
- Participants
- 20
- Ages
- 25–75
RCTSilymarin as an adjunct to glibenclamide therapy improves long-term and postprandial glycemic control and body mass index in type 2 diabetes2007
An RCT of 59 type 2 diabetes patients on glibenclamide found adding 200 mg/day silymarin for 120 days reduced fasting and postprandial glucose, HbA1c, and BMI vs placebo.
- Effect
- Benefit
- Duration
- 120 days
- Dose
- 200 mg/day
- Population
- Diabetic patients
RCTThe efficacy of Silybum marianum (L.) Gaertn. (silymarin) in the treatment of type II diabetes: a randomized, double-blind, placebo-controlled, clinical trial2006n=26
An RCT of 51 type 2 diabetes patients found silymarin 200 mg three times daily for 4 months reduced HbA1c, fasting glucose, total cholesterol, LDL, and triglycerides vs placebo.
- Effect
- Benefit
- Duration
- 4 months
- Dose
- 200 mg
- Population
- Diabetic patients
- Participants
- 26
NattokinaseView supplement →
Consider purchase·★★★★★
How we scored this▸
- Eating soy foods like natto or taking soy supplements may help control blood sugar and cholesterol in people with type 2 diabetes.
- Soy has natural compounds called isoflavones that may improve blood sugar levels and heart health.
- Some special extracts from fermented soybeans have also been shown to help people with mild diabetes reduce blood sugar.
- People who eat legumes and soy regularly may have a lower risk of developing type 2 diabetes.
- Some studies in Chinese people with diabetes found that eating soy foods was linked to a lower risk of heart-related deaths.
Browse 8 studies·5 meta-analyses
RCTDietary Soy Consumption and Cardiovascular Mortality among Chinese People with Type 2 Diabetes2021n=26,139
In 26,139 Chinese adults with type 2 diabetes, higher soy consumption was associated with lower cardiovascular mortality.
- Effect
- Benefit
- Duration
- 1–3 days
- Population
- Adults
- Participants
- 26,139
- Ages
- 30–79
MetaEffects of Soy Isoflavones on Glycemic Control and Lipid Profile in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2021
A meta-analysis of soy isoflavone RCTs in type 2 diabetes found significant reductions in total cholesterol (-0.21 mmol/L) and LDL-C (-0.20 mmol/L) but no effect on fasting glucose or HbA1c.
- Effect
- No Benefit
- Population
- Diabetic patients
MetaLegume and soy intake and risk of type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies2020n=565,810
A meta-analysis of 565,810 adults found tofu (RR 0.92), soy protein (RR 0.84), and soy isoflavones (RR 0.88) inversely associated with type 2 diabetes risk.
- Effect
- Benefit
- Population
- Adults
- Participants
- 565,810
MetaSoy isoflavones and glucose metabolism in menopausal women: A systematic review and meta-analysis of randomized controlled trials2016n=1,529
A meta-analysis of 17 RCTs (1529 menopausal women) found soy isoflavones reduced fasting glucose by 0.22 mmol/L, insulin by 0.43 μIU/mL, and HOMA-IR by 0.52 vs placebo.
- Effect
- Benefit
- Population
- Women
- Participants
- 1,529
MetaSoy Protein Supplementation Reduces Clinical Indices in Type 2 Diabetes and Metabolic Syndrome2016
A meta-analysis of soy protein RCTs in type 2 diabetes and metabolic syndrome found lower fasting glucose, insulin, HOMA-IR, diastolic BP, LDL-C, total cholesterol, and CRP vs control.
- Effect
- Benefit
- Population
- Adults
MetaEffects of soy intake on glycemic control: a meta-analysis of randomized controlled trials2011n=1,518
A meta-analysis of 24 RCTs (1518 subjects) found soy intake had mixed effects on glycemic measures, with some trials showing modest improvements in fasting glucose and HOMA-IR.
- Effect
- No Benefit
- Participants
- 1,518
RCTEfficacy and safety of Touchi extract, an alpha-glucosidase inhibitor derived from fermented soybeans, in non-insulin-dependent diabetes mellitus2001
In 18 type 2 diabetic patients, 0.9 g/day Touchi extract (alpha-glucosidase inhibitor) for 6 months lowered blood glucose and HbA1c; 9 healthy subjects tolerated 3 g/day for 12 weeks without adverse lab changes.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 3 g/day
- Population
- Healthy adults
RCTLong-term ingestion of a fermented soybean-derived Touchi-extract with alpha-glucosidase inhibitory activity is safe and effective in humans with borderline and mild type-2 diabetes2001n=36
In 36 adults with borderline or mild type 2 diabetes, 0.9 g/day Touchi extract for 3 months reduced fasting glucose (6.9 to 6.4 mmol/L) and HbA1c (6.1% to 5.6%) vs placebo.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 0.9 g/day
- Population
- Adults
- Participants
- 36
Panax GinsengView supplement →
Consider purchase·★★★★★
How we scored this▸
- Research on Panax ginseng for blood sugar control in diabetes is mixed.
- Some studies show small improvements in fasting blood sugar, but most do not show changes in long-term markers like HbA1c or insulin levels.
- Some ginseng preparations may help more than others, and effects might vary depending on the dose and type of product used.
- More research is needed to confirm these benefits.
Browse 8 studies·3 meta-analyses
RCTEffects of Panax ginseng on hyperglycemia, hypertension, and hyperlipidemia: A systematic review and meta-analysis2022
A meta-analysis of 23 studies found Panax ginseng significantly reduced glucose, insulin, body fat, blood pressure, total cholesterol, triglycerides, and LDL-C versus placebo across metabolic conditions.
- Effect
- Benefit
- Duration
- 4–24 weeks
- Dose
- 200 mg/day
- Population
- Healthy adults
MetaEffects of Panax ginseng on hyperglycemia, hypertension, and hyperlipidemia: A systematic review and meta-analysis2021
A meta-analysis of 23 studies found Panax ginseng significantly reduced glucose, insulin, body fat, blood pressure, total cholesterol, triglycerides, and LDL-C versus placebo across metabolic conditions.
- Effect
- Benefit
- Duration
- 4–24 weeks
- Dose
- 200 mg/day
- Population
- Healthy adults
RCTPostprandial glucose-lowering effects of fermented red ginseng in subjects with impaired fasting glucose or type 2 diabetes: a randomized, double-blind, placebo-controlled clinical trial2014n=42
In 42 adults with impaired fasting glucose or type 2 diabetes, fermented red ginseng for 4 weeks lowered postprandial glucose and insulin AUC versus placebo without changing fasting lipids.
- Effect
- Benefit
- Duration
- 4 weeks
- Population
- Adults
- Participants
- 42
- Ages
- 20–75
MetaThe effect of ginseng (the genus Panax) on glycemic control: a systematic review and meta-analysis of randomized controlled clinical trials2014n=770
A meta-analysis of 16 RCTs (n=770) found ginseng significantly lowered fasting blood glucose −0.31 mmol/L (p=0.03) but not HbA1c or insulin overall.
- Effect
- Benefit
- Participants
- 770
RCTGinseng and ginsenoside Re do not improve β-cell function or insulin sensitivity in overweight and obese subjects with impaired glucose tolerance or diabetes2011
In overweight adults with impaired glucose tolerance or new type 2 diabetes, ginseng 8 g/day or ginsenoside Re for 30 days did not improve beta-cell function or insulin sensitivity versus placebo.
- Effect
- No Benefit
- Duration
- 30 days
- Dose
- 8 g/day
- Population
- Overweight adults
- Avg age
- 46±3
MetaRed ginseng for type 2 diabetes mellitus: a systematic review of randomized controlled trials2011n=76
A systematic review of 4 RCTs found red ginseng did not significantly improve fasting glucose or insulin in type 2 diabetes (WMD −0.43 mmol/L, p=0.25).
- Effect
- No Benefit
- Duration
- 12 weeks
- Population
- Patients with type 2 diabetes
- Participants
- 76
RCTKorean red ginseng (Panax ginseng) improves glucose and insulin regulation in well-controlled, type 2 diabetes: results of a randomized, double-blind, placebo-controlled study of efficacy and safety2008
In 19 well-controlled type 2 diabetes patients, Korean red ginseng rootlets 6 g/day for 12 weeks lowered postprandial glucose 8–11% and insulin 33–38% versus placebo without changing HbA1c.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 6 g/day
- Avg age
- 64±2
Controlled trialGinseng therapy in non-insulin-dependent diabetic patients1995
In 36 newly diagnosed NIDDM patients, ginseng 100–200 mg/day for 8 weeks improved mood, performance, fasting glucose, and glycated hemoglobin at 200 mg versus placebo.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 200 mg/day
- Population
- Diabetic patients
TaurineView supplement →
Consider purchase·★★★★★
How we scored this▸
- It is unclear if taurine supplements help people with diabetes.
- People with diabetes often have lower taurine levels in their blood.
- Some small studies suggest taurine might lower blood sugar and cholesterol and improve how the body uses insulin, but results are mixed.
- Taking taurine while exercising might help reduce blood sugar more than exercise alone.
- Larger studies are needed to confirm if taurine is helpful for diabetes.
Browse 5 studies·1 meta-analysis
MetaEffect of Long-Term Taurine Supplementation on the Lipid and Glycaemic Profile in Adults with Overweight or Obesity: A Systematic Review and Meta-Analysis2024
In adults with overweight or obesity over 12 weeks, long-term taurine supplementation improved some lipid and glycemic markers versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 3 g/day
- Population
- Adults
RCTThe Effects of TRX Suspension Training Combined with Taurine Supplementation on Body Composition, Glycemic and Lipid Markers in Women with Type 2 Diabetes2021n=10
In 40 women with type 2 diabetes, 8 weeks of TRX training plus taurine improved body composition and blood glucose markers more than exercise alone.
- Effect
- Benefit
- Population
- Women
- Participants
- 10
- Avg age
- 53±5
RCTThe effects of taurine supplementation on glycemic control and serum lipid profile in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled trial2020n=23
An RCT of 45 type 2 diabetes patients found that 3000 mg/day taurine for 8 weeks significantly reduced fasting blood sugar, insulin, HOMA-IR, total cholesterol, and LDL-C versus placebo.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 3000 mg/day
- Population
- Diabetic patients
- Participants
- 23
ObservationalThe Relationship between Plasma Taurine Levels and Diabetic Complications in Patients with Type 2 Diabetes Mellitus2019n=38
An observational study of 59 adults with type 2 diabetes found lower plasma taurine in diabetic patients, with the lowest levels associated with neuropathy.
- Population
- Diabetic patients
- Participants
- 38
- Ages
- 32–82
RCTThe effect of taurine supplementation on patients with type 2 diabetes mellitus2003
A clinical trial reported that taurine supplementation improved metabolic markers in patients with type 2 diabetes mellitus.
- Effect
- Benefit
- Population
- Diabetic patients
ZincView supplement →
Consider purchase·★★★★★
How we scored this▸
- Taking zinc supplements may slightly improve blood sugar control in people with diabetes.
- Studies found that zinc can lower fasting blood sugar by up to 20 mg/dL and reduce a key blood sugar marker (HbA1c) by about 0.35%.
- These effects are mostly seen in people from the Eastern hemisphere and with daily doses of at least 30 mg taken for a month or more.
- Zinc also lowers triglycerides but does not change good or bad cholesterol.
- For women with gestational diabetes, taking zinc gluconate during late pregnancy may lower fasting blood sugar and improve insulin sensitivity but does not reduce the chance of cesarean delivery or improve baby health at birth.
Browse 4 studies·2 meta-analyses
MetaEffects of zinc supplementation on lipid profile in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials2020n=424
A meta-analysis of nine RCTs in 424 type 2 diabetes patients found zinc supplementation significantly lowered triglycerides by 17.1 mg/dL and total cholesterol by 26.2 mg/dL, with HDL increases in several subgroups.
- Effect
- Benefit
- Dose
- 3.58 mg/day
- Population
- Diabetic patients
- Participants
- 424
MetaZinc supplementation improves glycemic control for diabetes prevention and management: a systematic review and meta-analysis of randomized controlled trials2019n=1,700
A meta-analysis of 32 RCTs in 1,700 participants found zinc supplementation reduced fasting glucose by 14.2 mg/dL, HbA1c by 0.55%, fasting insulin, and insulin resistance versus placebo.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 1,700
RCTZinc Supplementation and the Effects on Pregnancy Outcomes in Gestational Diabetes: a Randomized, Double-blind, Placebo-controlled Trial2016n=25
In 50 women with gestational diabetes, 30 mg/day zinc for 6 weeks lowered hs-CRP and raised total antioxidant capacity versus placebo but did not significantly change pregnancy outcomes.
- Effect
- No Benefit
- Duration
- 6 weeks
- Dose
- 30 mg/day
- Population
- Women
- Participants
- 25
RCTZinc supplementation and the effects on metabolic status in gestational diabetes: A randomized, double-blind, placebo-controlled trial2015n=29
In 58 women with gestational diabetes, 30 mg/day zinc for 6 weeks reduced fasting glucose, insulin, and HOMA-IR and increased insulin sensitivity versus placebo, without affecting most other lipids.
- Effect
- Benefit
- Duration
- 6 weeks
- Dose
- 30 mg/day
- Population
- Women
- Participants
- 29
- Ages
- 18–40
BerberineView supplement →
Consider purchase·★★★★★
How we scored this▸
- Berberine can help lower blood sugar in people with type 2 diabetes.
- Studies show taking 500 mg of berberine two or three times a day for a few months can reduce blood sugar levels and HbA1c, similar to standard diabetes drugs like metformin.
- When combined with other diabetes medicines or probiotics, berberine may provide extra blood sugar and cholesterol improvements.
- Berberine works by helping the body use insulin better, much like metformin.
Browse 10 studies·5 meta-analyses
RCTEffects of administering berberine alone or in combination on type 2 diabetes mellitus: a systematic review and meta-analysis2024n=4,150
A 2024 meta-analysis of 50 RCTs in 4,150 type 2 diabetes patients found berberine alone or combined lowered fasting glucose, postprandial glucose, HbA1c, lipids, and inflammatory markers.
- Effect
- Benefit
- Duration
- 1–3 months
- Dose
- 0.9–1.5 g/day berberine
- Participants
- 4,150
RCTCombined berberine and probiotic treatment as an effective regimen for improving postprandial hyperlipidemia in type 2 diabetes patients: a double-blind placebo-controlled randomized study2022n=365
A 12-week RCT of 365 type 2 diabetes patients found berberine plus probiotics lowered postprandial cholesterol and lipid metabolites more than either treatment alone.
- Effect
- Benefit
- Duration
- 12 weeks
- Population
- Patients with type 2 diabetes
- Participants
- 365
- Ages
- 20–70
Systematic reviewGlucose-lowering effect of berberine on type 2 diabetes: a systematic review and meta-analysis2022n=3,048
A meta-analysis of 37 RCTs in 3,048 type 2 diabetes patients found berberine reduced fasting glucose 0.82 mmol/L, HbA1c 0.63%, and 2-hour glucose 1.16 mmol/L without increasing hypoglycemia risk.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 3,048
RCTEffectiveness and safety of Bifidobacterium and berberine in human hyperglycemia and their regulatory effect on the gut microbiota: a multi-center, double-blind, randomized, parallel-controlled study2021n=297
A 16-week multicenter RCT of 297 newly hyperglycemic adults found berberine alone or with Bifidobacterium lowered fasting glucose about 0.5 mmol/L versus placebo and shifted gut microbiota.
- Effect
- Benefit
- Duration
- 16 weeks
- Population
- Women
- Participants
- 297
- Ages
- 18–70
MetaThe effect of berberine on metabolic profiles in type 2 diabetic patients: a systematic review and meta-analysis of randomized controlled trials2021n=60
A meta-analysis of 46 type 2 diabetes RCTs found berberine reduced HbA1c, fasting and postprandial glucose, insulin resistance, LDL, triglycerides, and inflammatory markers.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 60
- Ages
- 18+
MetaMeta-analysis of the effect and safety of berberine in the treatment of type 2 diabetes mellitus, hyperlipemia and hypertension2015n=2,569
A meta-analysis of 27 RCTs in 2,569 patients found berberine comparably improved glucose, lipids, and blood pressure in type 2 diabetes, hyperlipidemia, and hypertension with no serious adverse events.
- Effect
- Benefit
- Population
- Type 2 diabetes, hyperlipidemia, and hypertension patients
- Participants
- 2,569
RCTBerberine in the treatment of type 2 diabetes mellitus: a systemic review and meta-analysis2012n=1,068
A meta-analysis of 14 RCTs in 1,068 type 2 diabetes patients found berberine improved hyperglycemia and dyslipidemia, especially when combined with oral hypoglycemics, without serious adverse effects.
- Effect
- Benefit
- Participants
- 1,068
RCTBerberine lowers blood glucose in type 2 diabetes mellitus patients through increasing insulin receptor expression2010
Clinical and cell studies found berberine increased insulin receptor expression and lowered fasting glucose and HbA1c in type 2 diabetes patients with efficacy similar to metformin or rosiglitazone.
- Effect
- Benefit
- Population
- Diabetic patients
RCTEfficacy of berberine in patients with type 2 diabetes mellitus2008n=48
A pilot study in 36 newly diagnosed and 48 poorly controlled type 2 diabetes patients found berberine 1.5 g/day for 3 months lowered HbA1c, fasting and postprandial glucose similar to metformin, with transient GI effects in 35%.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 1.5 g/day
- Population
- Adults
- Participants
- 48
RCTTreatment of type 2 diabetes and dyslipidemia with the natural plant alkaloid berberine2008n=16
A 3-month RCT of 116 type 2 diabetes patients with dyslipidemia found 1 g/day berberine lowered fasting glucose, HbA1c, triglycerides, and LDL-C and raised glucose disposal rate versus placebo.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 1.0 g/day
- Population
- Diabetic patients
- Participants
- 16
CaffeineView supplement →
Consider purchase·★★★★★
How we scored this▸
- Dietary caffeine intake, mainly from coffee and tea, is associated with a dose-dependent lower risk of developing type 2 diabetes, with higher caffeine consumption linked to up to a 33% reduction in incidence in some populations.
- However, its role in preventing gestational diabetes or managing glycemia in type 1 or type 2 diabetes patients is unclear.
- Some small studies indicate caffeine may decrease insulin sensitivity and alter hypoglycemia awareness in diabetic patients, but overall evidence is inconclusive, requiring further research for definitive conclusions.
Browse 14 studies·2 meta-analyses
RCTCombined intake of caffeine and low-dose glucose to reduce exercise-related hypoglycaemia in individuals with type 1 diabetes on ultra-long-acting insulin degludec: A randomized, controlled, double-blind, cross-over trial2024n=16
In 16 adults with type 1 diabetes on insulin degludec, pre-exercise caffeine 250 mg plus 10 g glucose reduced exercise-related hypoglycemia risk by 86% versus aspartame control without causing hyperglycemia.
- Effect
- Benefit
- Dose
- 250 mg/day
- Population
- Adults
- Participants
- 16
ObservationalAssessment of Caffeine Consumption and Maternal Cardiometabolic Pregnancy Complications2021n=54
In 2,583 pregnant women, second-trimester caffeinated beverage intake 1–100 mg/day was associated with lower gestational diabetes risk and better glucose and lipid profiles; no links to preeclampsia or gestational hypertension were found.
- Effect
- Benefit
- Dose
- 200 mg/day
- Population
- Women
- Participants
- 54
- Avg age
- ~28
ObservationalLong-term effects of coffee and caffeine intake on the risk of pre-diabetes and type 2 diabetes: Findings from a population with low coffee consumption2018n=29
In 1,878–2,139 Iranian adults followed ~5.8 years, coffee drinkers had lower incidence of pre-diabetes (HR 0.73) and type 2 diabetes (HR 0.66) versus non-drinkers after adjustment.
- Effect
- Benefit
- Dose
- 6.5 mg/kg
- Population
- Adults
- Participants
- 29
- Ages
- 20–70
MetaCaffeinated and decaffeinated coffee consumption and risk of type 2 diabetes: a systematic review and a dose-response meta-analysis2014
A dose-response meta-analysis of 28 prospective studies found each additional cup of coffee associated with lower type 2 diabetes risk for both caffeinated (RR 0.91 per cup) and decaffeinated coffee (RR 0.94).
- Effect
- Benefit
- Duration
- 10 months to 20 years
MetaCoffee and caffeine intake and incidence of type 2 diabetes mellitus: a meta-analysis of prospective studies2013n=491,485
A meta-analysis of prospective studies (up to 1,096,647 participants) found highest coffee intake associated with 29–30% lower type 2 diabetes incidence; each 2 cups/day reduced risk by 12% (caffeinated) to 14% (caffeine).
- Effect
- Benefit
- Dose
- 200 mg/day
- Population
- Women
- Participants
- 491,485
RCTAcute caffeine ingestion and glucose tolerance in women with or without gestational diabetes mellitus2009n=19
In 19 women with and without gestational diabetes, acute caffeine 3 mg/kg impaired insulin sensitivity and glucose tolerance in GDM patients but not in controls during an oral glucose tolerance test.
- Effect
- No Benefit
- Dose
- 3 mg/kg
- Population
- Women
- Participants
- 19
ObservationalCoffee and tea consumption and risk of type 2 diabetes2009n=40,011
In 40,011 Dutch adults over ~10 years, drinking 4.1–6.0 cups coffee/day or >5 cups tea/day was inversely associated with type 2 diabetes versus lower intake, independent of caffeine-related mediators tested.
- Effect
- Benefit
- Population
- Adults
- Participants
- 40,011
ObservationalDoes long-term coffee intake reduce type 2 diabetes mellitus risk?2009
A review of 14 of 18 cohort studies concluded moderate-to-high coffee/caffeine intake (≥4 cups or ≥400 mg/day) associates with lower type 2 diabetes risk, though causality and decaffeinated effects need more trial evidence.
- Effect
- Benefit
- Dose
- 400 mg/day
- Population
- Postmenopausal women
ObservationalThe relationship between green tea and total caffeine intake and risk for self-reported type 2 diabetes among Japanese adults2006n=231
In 17,413 Japanese adults aged 40–65 followed 5 years, ≥6 cups/day green tea (OR 0.67) and ≥3 cups/day coffee (OR 0.58) were inversely associated with self-reported type 2 diabetes; black or oolong tea were not.
- Effect
- Benefit
- Population
- Adults
- Participants
- 231
- Ages
- 40–65
RCTCaffeine ingestion is associated with reductions in glucose uptake independent of obesity and type 2 diabetes before and after exercise training2005n=8
In lean, obese, and type 2 diabetic men, acute caffeine 5 mg/kg reduced insulin-mediated glucose uptake during clamp testing; chronic exercise training did not remove this insulin-desensitizing effect.
- Effect
- No Benefit
- Dose
- 5 mg/kg
- Population
- Women
- Participants
- 8
RCTInfluence of caffeine on frequency of hypoglycemia detected by continuous interstitial glucose monitoring system in patients with long-standing type 1 diabetes2005n=19
In 19 women with long-standing type 1 diabetes monitored 4 weeks, caffeine reduced nocturnal hypoglycemia duration and shifted episodes from moderate to mild versus placebo without changing overall glycemic control.
- Effect
- Benefit
- Duration
- 4 weeks
- Population
- Women
- Participants
- 19
RCTCaffeine ingestion before an oral glucose tolerance test impairs blood glucose management in men with type 2 diabetes2004n=12
In 12 obese men with type 2 diabetes, caffeine 5 mg/kg before oral glucose loading raised post-load glucose and insulin despite higher proinsulin and C-peptide, indicating impaired glucose management.
- Effect
- No Benefit
- Dose
- 5 mg/kg
- Population
- Women
- Participants
- 12
- Avg age
- 49±2
ObservationalCoffee consumption and risk for type 2 diabetes mellitus2004n=10
In 126,270 U.S. men and women followed up to 18 years, higher coffee intake was inversely associated with type 2 diabetes incidence in a dose-response pattern for regular and decaffeinated coffee.
- Effect
- Benefit
- Population
- Adults
- Participants
- 10
RCTInfluence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes2000n=34
In 34 type 1 diabetes patients over 3 months, caffeine 200 mg/day increased symptomatic hypoglycemia episodes and symptom intensity versus placebo without worsening HbA1c or causing severe hypoglycemia.
- Effect
- No Benefit
- Duration
- 3 months
- Dose
- 200 mg/day
- Population
- Women
- Participants
- 34
Cassia CinnamonView supplement →
Consider purchase·★★★★★
How we scored this▸
- Research on cassia cinnamon for type 2 diabetes shows mixed results.
- Some studies and reviews suggest that it may help lower blood sugar and improve cholesterol levels, but other studies find little or no benefit.
- One large review showed that cinnamon could lower fasting blood sugar, LDL (“bad”) cholesterol, and triglycerides, while raising HDL (“good”) cholesterol.
- However, a more recent review found no benefit when cinnamon bark powder was used in typical doses.
- Its effects on long-term blood sugar control (HbA1c) are also unclear.
- Some studies show modest lowering of HbA1c, while others show no change.
- Differences may depend on the type of cinnamon used, the dose, how long it’s taken, and whether patients are already on diabetes medication.
- In some studies, combinations of cinnamon with other plant extracts lowered blood sugar and HbA1c to a degree similar to the drug metformin, but it is uncertain whether cinnamon itself was responsible for these improvements.
- In people with type 1 diabetes, studies show that cassia cinnamon does not help control blood sugar or reduce low blood sugar episodes.
Browse 21 studies·7 meta-analyses
MetaEffects of cinnamon supplementation on metabolic biomarkers in individuals with type 2 diabetes: a systematic review and meta-analysis2025n=3,054
A meta-analysis of RCTs in type 2 diabetes found cinnamon supplementation reduced fasting glucose, HbA1c, and insulin resistance markers over 30–120 days.
- Effect
- Benefit
- Duration
- 30–120 days
- Dose
- 2 g/day
- Population
- Older adults
- Participants
- 3,054
RCTThe efficacy and safety of berberine in combination with cinnamon supplementation in patients with type 2 diabetes: a randomized clinical trial2025
A 12-week double-blind RCT in type 2 diabetes patients found 1,200 mg/day berberine plus 600 mg/day cinnamon lowered fasting glucose, HbA1c, and LDL-C versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 1200 mg/day
- Population
- Diabetic patients
MetaThe effect of cinnamon supplementation on glycemic control in patients with type 2 diabetes mellitus: An updated systematic review and dose-response meta-analysis of randomized controlled trials2023
An updated meta-analysis of 24 T2DM RCTs found cinnamon lowered fasting glucose, HbA1c, and HOMA-IR vs control; insulin levels did not change significantly.
- Effect
- Benefit
- Duration
- 8–12 weeks
- Dose
- 2 g/day
- Population
- Diabetic patients
RCTA Phase II, Randomized, Double-Blind, Double-Dummy, Active-Controlled Clinical Trial to Investigate the Efficacy and Safety of NW Low-Glu® in Patients Newly Diagnosed with Type 2 Diabetes Mellitus2022n=68
A 12-week phase 2 RCT in newly diagnosed T2DM found low- and high-dose cinnamon-containing NW Low-Glu capsules reduced HbA1c similarly to metformin.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 2000 mg/day
- Population
- Adults
- Participants
- 68
- Ages
- 18–65
Systematic reviewEfficacy of cinnamon supplementation on glycolipid metabolism in T2DM diabetes: A meta-analysis and systematic review2022n=1,020
A systematic review of cinnamon RCTs in T2DM concluded supplementation improves glycemic and some lipid measures, though active components and mechanisms remain unclear.
- Effect
- Benefit
- Population
- Infants
- Participants
- 1,020
RCTImpact of Cassia Bark Consumption on Glucose and Lipid Control in Type 2 Diabetes: An Updated Systematic Review and Meta-Analysis2021
A meta-analysis of cassia cinnamon trials using 1–2 g/day ground bark for 90 days found modest improvements in fasting glucose and some lipids in type 2 diabetes.
- Effect
- No Benefit
- Duration
- 90 days
- Dose
- 1–2 g/day
- Population
- Adults
RCTCinnamon extract lowers glucose, insulin and cholesterol in people with elevated serum glucose2015
A randomized trial in people with elevated blood glucose found cinnamon extract reduced fasting glucose, insulin, and total cholesterol, suggesting possible adjunct benefit for prediabetes and diabetes.
- Effect
- Benefit
MetaCinnamon use in type 2 diabetes: an updated systematic review and meta-analysis2013n=543
A meta-analysis of 10 RCTs (543 patients) found cinnamon doses of 120 mg to 6 g/day for 4–18 weeks lowered fasting glucose, total cholesterol, LDL, and triglycerides and raised HDL, but did not significantly change HbA1c.
- Effect
- Benefit
- Duration
- 4–18 weeks
- Dose
- 120–6000 mg/day
- Population
- Diabetic patients
- Participants
- 543
RCTCinnamon extract improves fasting blood glucose and glycosylated hemoglobin level in Chinese patients with type 2 diabetes2012n=66
In 66 Chinese adults with type 2 diabetes on gliclazide, 120 or 360 mg/day cinnamon extract for 3 months significantly reduced fasting glucose and HbA1c versus placebo; triglycerides fell in the low-dose group.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 120–360 mg
- Population
- Adults
- Participants
- 66
MetaCinnamon for diabetes mellitus2012n=577
A Cochrane review of 10 RCTs (577 participants) found 2 g/day cinnamon for 4–16 weeks did not significantly improve fasting glucose, HbA1c, insulin, or postprandial glucose in type 1 or type 2 diabetes.
- Effect
- No Benefit
- Duration
- 4–16 weeks
- Dose
- 2 g/day
- Population
- Diabetic patients
- Participants
- 577
MetaCinnamon in glycaemic control: Systematic review and meta analysis2012n=435
A meta-analysis of 6 trials (435 patients) found cinnamon 1–6 g/day for 40 days to 4 months significantly reduced mean HbA1c by 0.09% and fasting glucose by 0.84 mmol/L in type 2 diabetes.
- Effect
- Benefit
- Duration
- 40 days
- Dose
- 6 g/day
- Population
- Diabetic patients
- Participants
- 435
RCTDietary cinnamon supplementation and changes in systolic blood pressure in subjects with type 2 diabetes2011n=59
In 59 adults with type 2 diabetes, 1,200 mg/day cinnamon for 12 weeks did not produce a treatment-associated systolic blood pressure reduction after adjusting for baseline blood pressure.
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 200 mg/day
- Population
- Adults
- Participants
- 59
- Ages
- 18–65
RCTGlycated haemoglobin and blood pressure-lowering effect of cinnamon in multi-ethnic Type 2 diabetic patients in the UK: a randomized, placebo-controlled, double-blind clinical trial2010
In 58 poorly controlled UK type 2 diabetes patients, 2 g/day cinnamon for 12 weeks significantly reduced HbA1c, systolic and diastolic blood pressure, fasting glucose, waist circumference, and BMI versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 2 g/day
- Population
- Diabetic patients
- Avg age
- ~55
RCTEffectiveness of cinnamon for lowering hemoglobin A1C in patients with type 2 diabetes: a randomized, controlled trial2009n=109
A randomized trial of 109 type 2 diabetes patients found 1 g/day cinnamon for 90 days lowered HbA1c by 0.83% versus 0.37% with usual care alone in patients with baseline HbA1c above 7%.
- Effect
- Benefit
- Duration
- 90 days
- Dose
- 1 g/day
- Population
- Adults
- Participants
- 109
MetaEffect of cinnamon on glucose control and lipid parameters2008n=282
A meta-analysis of 5 RCTs (282 participants) found cinnamon did not significantly change A1C, fasting glucose, or lipid parameters in patients with type 1 or type 2 diabetes.
- Effect
- No Benefit
- Population
- Patients with type 2 diabetes
- Participants
- 282
RCTEffect of cinnamon on glucose and lipid levels in non insulin-dependent type 2 diabetes2007
A randomized controlled trial reported that cinnamon supplementation reduced serum glucose and triglycerides in non–insulin-dependent type 2 diabetes, though published abstract details were limited.
RCTThe effect of cinnamon on A1C among adolescents with type 1 diabetes2007
In 72 adolescents with type 1 diabetes, 1 g/day cinnamon for 90 days did not improve final A1C, A1C change, daily insulin use, or hypoglycemic episodes versus placebo.
- Effect
- No Benefit
- Duration
- 3 months
- Dose
- 1 g/day
- Population
- Diabetic patients
Controlled trialCinnamon supplementation does not improve glycemic control in postmenopausal type 2 diabetes patients2006
In 25 postmenopausal women with type 2 diabetes, 1.5 g/day cinnamon for 6 weeks did not improve insulin sensitivity, oral glucose tolerance, or fasting lipids versus placebo.
- Effect
- No Benefit
- Duration
- 6 weeks
- Dose
- 1.5 g/day
- Population
- Postmenopausal women
- Avg age
- ~63
RCTEffects of a cinnamon extract on plasma glucose, HbA, and serum lipids in diabetes mellitus type 22006n=79
In 79 type 2 diabetes patients, aqueous cinnamon extract equivalent to 3 g/day for 4 months significantly reduced fasting glucose by 10.3% versus 3.4% with placebo; HbA1c and lipids did not differ between groups.
- Effect
- Benefit
- Duration
- 4 months
- Dose
- 3 g/day
- Population
- Diabetic patients
- Participants
- 79
RCTThe effect of cinnamon cassia powder in type 2 diabetes mellitus2006
In 60 type 2 diabetes patients, 1.5 g/day cinnamon cassia powder for 12 weeks did not significantly reduce fasting glucose, HbA1c, or lipids versus placebo, though SGOT improved in the cinnamon group.
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 1.5 g/day
- Population
- Diabetic patients
RCTCinnamon improves glucose and lipids of people with type 2 diabetes2003n=60
In 60 adults with type 2 diabetes, 1, 3, or 6 g/day cinnamon for 40 days reduced fasting glucose (18–29%), triglycerides (23–30%), LDL (7–27%), and total cholesterol (12–26%) versus placebo.
- Effect
- Benefit
- Duration
- 40 days
- Dose
- 6 g/day
- Population
- Adults
- Participants
- 60
- Avg age
- ~52
ChromiumView supplement →
Consider purchase·★★★★★
How we scored this▸
- Chromium supplements may help improve blood sugar control in people with type 2 diabetes, especially if taken in higher doses (over 200 mcg daily) and if diabetes is not well controlled.
- Some studies show chromium can lower long-term blood sugar (HbA1c) by a small amount and may improve some cholesterol levels.
- However, the evidence is mixed and not strong enough to recommend chromium as a main treatment.
- The FDA says the evidence that chromium lowers diabetes risk is uncertain.
- More research is needed.
Browse 42 studies·9 meta-analyses
MetaComparative effects of vitamin and mineral supplements in the management of type 2 diabetes in primary care: A systematic review and network meta-analysis of randomized controlled trials2023n=14,223
A network meta-analysis of 170 trials (14,223 participants) ranked chromium supplements highest for lowering fasting glucose and insulin resistance among micronutrient options in type 2 diabetes.
- Effect
- Benefit
- Population
- Healthy adults
- Participants
- 14,223
MetaEffects of chromium supplementation on body composition in patients with type 2 diabetes: A dose-response systematic review and meta-analysis of randomized controlled trials2023
A 2023 meta-analysis of 14 RCTs found chromium supplementation did not significantly change body weight, BMI, waist circumference, or fat mass in type 2 diabetes overall.
- Effect
- No Benefit
- Dose
- 400 mcg/day
- Population
- Diabetic patients
- Ages
- 55+
MetaEffect of Chromium Supplementation on Blood Glucose and Lipid Levels in Patients with Type 2 Diabetes Mellitus: a Systematic Review and Meta-analysis2021n=509
A meta-analysis of 10 RCTs (509 patients) found chromium supplements significantly reduced HbA1c in type 2 diabetes but did not significantly improve fasting glucose or lipids.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 509
MetaEffects of chromium supplementation on blood pressure, body mass index, liver function enzymes and malondialdehyde in patients with type 2 diabetes: A systematic review and dose-response meta-analysis of randomized controlled trials2021
A meta-analysis of 15 RCTs found chromium 200–1,000 µg/day significantly reduced diastolic blood pressure and malondialdehyde in type 2 diabetes without affecting BMI or liver enzymes.
- Effect
- No Benefit
- Dose
- 1000 mcg/day
- Population
- Diabetic patients
MetaEffects of chromium supplementation on lipid profile in patients with type 2 diabetes: A systematic review and dose-response meta-analysis of randomized controlled trials2021
A meta-analysis of 24 RCTs found chromium supplementation modestly lowered triglycerides and total cholesterol and raised HDL in type 2 diabetes, though LDL changes were not significant.
- Effect
- Benefit
- Dose
- 400 mcg/day
- Population
- Diabetic patients
RCTEffects of Chromium Picolinate Supplementation on Cardiometabolic Biomarkers in Patients with Type 2 Diabetes Mellitus: a Randomized Clinical Trial2020n=52
In 52 type 2 diabetes patients over 8 weeks, 400 µg/day chromium picolinate improved HOMA-IR, total cholesterol, and LDL versus placebo but did not change fasting glucose or weight.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 400 mcg/day
- Population
- Diabetic patients
- Participants
- 52
- Ages
- 40+
MetaEffects of chromium supplementation on glycemic control in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials2020
A 2020 meta-analysis of 28 trials found chromium supplementation significantly reduced fasting glucose, insulin, HbA1c, and HOMA-IR in type 2 diabetes.
- Effect
- Benefit
- Population
- Diabetic patients
RCTThe effects of chromium and vitamin D3 co-supplementation on insulin resistance and tumor necrosis factor-alpha in type 2 diabetes: a randomized placebo-controlled trial2020n=23
In 92 type 2 diabetes patients over 4 months, chromium plus vitamin D3 prevented HOMA-IR increases seen with vitamin D3 alone, but did not significantly change HbA1c or lipids.
- Effect
- Benefit
- Duration
- 4 months
- Dose
- 500 μg/day
- Population
- Healthy adults
- Participants
- 23
RCTThe Influences of Chromium Supplementation on Metabolic Status in Patients with Type 2 Diabetes Mellitus and Coronary Heart Disease2020n=32
In 64 diabetic patients with coronary heart disease over 12 weeks, 200 µg/day chromium reduced weight, fasting glucose, insulin resistance, hs-CRP, and diastolic blood pressure versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 200 mcg/day
- Population
- Diabetic patients
- Participants
- 32
RCTBeneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study2015n=39
In 71 poorly controlled type 2 diabetes patients over 4 months, 600 µg/day chromium picolinate reduced fasting and postprandial glucose and lowered HbA1c more than placebo.
- Effect
- Benefit
- Duration
- 4 months
- Dose
- 600 mcg/day
- Population
- Diabetic patients
- Participants
- 39
MetaEffect of chromium supplementation on glycated hemoglobin and fasting plasma glucose in patients with diabetes mellitus2015n=875
A meta-analysis of 14 RCTs found brewer's yeast chromium lowered fasting glucose by 19 mg/dL in type 2 diabetes but did not significantly affect HbA1c.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 875
- Ages
- 30–83
MetaSystematic review and meta-analysis of the efficacy and safety of chromium supplementation in diabetes2014
A 2014 meta-analysis of 25 RCTs found chromium monotherapy significantly improved HbA1c and fasting glucose in diabetes, with greatest effects above 200 µg/day and in poorly controlled patients.
- Effect
- Benefit
- Dose
- 200 mcg/day
- Population
- Diabetic patients
RCTChromium nicotinate has no effect on insulin sensitivity, glycemic control, and lipid profile in subjects with type 2 diabetes2013n=56
In 56 type 2 diabetes patients over 90 days, chromium nicotinate at 50 or 200 µg/day did not improve glycemic control or insulin sensitivity versus placebo.
- Effect
- No Benefit
- Duration
- 90 days
- Dose
- 200 mcg/day
- Population
- Diabetic patients
- Participants
- 56
MetaImproved meta-analytic methods show no effect of chromium supplements on fasting glucose2013n=809
An updated meta-analysis of 16 trials (809 participants) found chromium supplementation did not significantly improve fasting glucose in diabetic or nondiabetic adults.
- Effect
- No Benefit
- Population
- Adults
- Participants
- 809
RCTEffect of chromium dinicocysteinate supplementation on circulating levels of insulin, TNF-α, oxidative stress, and insulin resistance in type 2 diabetic subjects: randomized, double-blind, placebo-controlled study2012n=100
In 74 type 2 diabetes patients over 3 months, chromium dinicocysteinate reduced insulin resistance, TNF-α, and oxidative stress versus baseline, while chromium picolinate did not.
- Effect
- Benefit
- Duration
- 3 months
- Population
- Diabetic patients
- Participants
- 100
RCTBeneficial effect of chromium supplementation on glucose, HbA1C and lipid variables in individuals with newly onset type-2 diabetes2011
In 40 newly diagnosed type 2 diabetes patients over 3 months, brewer's yeast providing 42 µg/day chromium significantly lowered fasting glucose, HbA1c, and lipids versus placebo.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 42 mcg/day
- Population
- Healthy adults
RCTEffects of chromium brewer's yeast supplementation on body mass, blood carbohydrates, and lipids and minerals in type 2 diabetic patients2011
In 20 type 2 diabetes patients over 8 weeks, chromium-enriched brewer's yeast 500 µg/day improved beta-cell function but had only weak hypoglycemic effects.
- Effect
- No Benefit
- Duration
- 8 weeks
- Dose
- 500 mcg/day
- Population
- Adults
- Ages
- 37–63
RCTCharacterization of the metabolic and physiologic response to chromium supplementation in subjects with type 2 diabetes mellitus2009
In type 2 diabetes patients, 1,000 µg/day chromium improved insulin sensitivity mainly in responders with higher baseline glucose and HbA1c, and reduced myocellular lipids.
- Effect
- Benefit
- Dose
- 1000 mcg/day
- Population
- Diabetic patients
RCTAntioxidant effects and insulin resistance improvement of chromium combined with vitamin C and E supplementation for type 2 diabetes mellitus2008n=30
In 30 type 2 diabetes patients over 6 months, chromium yeast alone or with vitamins C and E reduced oxidative stress markers and improved glucose metabolism versus placebo.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 1000 mg
- Population
- Adults
- Participants
- 30
- Ages
- <56
RCTChromium picolinate and biotin combination improves glucose metabolism in treated, uncontrolled overweight to obese patients with type 2 diabetes2008n=47
In 447 poorly controlled type 2 diabetic adults, 90 days of chromium picolinate (600 µg) plus biotin (2 mg) lowered HbA1c by 0.54% versus placebo, with greater fasting glucose reductions in those with baseline HbA1c ≥10%.
- Effect
- Benefit
- Duration
- 90 days
- Dose
- 2 mg
- Population
- Diabetic patients
- Participants
- 47
RCTChromium treatment has no effect in patients with type 2 diabetes in a Western population: a randomized, double-blind, placebo-controlled trial2007
In Western type 2 diabetes patients on oral hypoglycemics, 400 µg/day chromium yeast for 6 months did not improve HbA1c, lipids, or insulin resistance versus placebo.
- Effect
- No Benefit
- Duration
- 6 months
- Dose
- 400 mcg/day
- Population
- Diabetic patients
RCTPhenotype of subjects with type 2 diabetes mellitus may determine clinical response to chromium supplementation2007
In 73 type 2 diabetes patients over 6 months, 1,000 µg/day chromium picolinate improved insulin sensitivity in 63% of patients, with baseline insulin sensitivity predicting response.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 1000 mcg/day
- Population
- Diabetic patients
RCTChromium picolinate supplementation attenuates body weight gain and increases insulin sensitivity in subjects with type 2 diabetes2006n=17
In 37 type 2 diabetes patients on sulfonylurea over 6 months, 1,000 µg/day chromium picolinate improved insulin sensitivity and attenuated weight and fat gain versus placebo.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 1000 mcg/day
- Population
- Diabetic patients
- Participants
- 17
RCTChromium treatment has no effect in patients with poorly controlled, insulin-treated type 2 diabetes in an obese Western population: a randomized, double-blind, placebo-controlled trial2006n=46
In 46 obese insulin-treated type 2 diabetes patients over 6 months, chromium picolinate up to 1,000 µg/day did not improve HbA1c or other metabolic endpoints versus placebo.
- Effect
- No Benefit
- Duration
- 6 months
- Dose
- 1000 mcg/day
- Population
- Diabetic patients
- Participants
- 46
RCTInfluence of chromium-enriched yeast on blood glucose and insulin variables, blood lipids, and markers of oxidative stress in subjects with type 2 diabetes mellitus2006n=19
In 36 type 2 diabetes patients over 12 weeks, 400 µg/day chromium-enriched yeast significantly reduced fasting glucose versus placebo without changing HbA1c.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 400 mcg/day
- Population
- Diabetic patients
- Participants
- 19
- Avg age
- 61.3
RCTThe effect of chromium picolinate and biotin supplementation on glycemic control in poorly controlled patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial2006
In 43 type 2 diabetic patients, 4 weeks of chromium picolinate plus biotin (2 mg/day) reduced 2-h oral glucose tolerance area under the curve and fructosamine versus placebo, without serious adverse events.
- Effect
- Benefit
- Duration
- 4 weeks
- Dose
- 2 mg/day
- Population
- Diabetic patients
RCTThe influence of chromium chloride-containing milk to glycemic control of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial2006n=60
In 60 type 2 diabetes patients over 16 weeks, chromium-fortified milk 400 µg/day lowered fasting glucose and insulin mainly in male patients versus placebo.
- Effect
- Benefit
- Duration
- 16 weeks
- Dose
- 400 mcg/day
- Population
- Diabetic patients
- Participants
- 60
- Ages
- 30–75
RCTChromium supplementation shortens QTc interval duration in patients with type 2 diabetes mellitus2005n=60
In 60 type 2 diabetes patients, 1,000 µg/day chromium picolinate for 3 months shortened QTc interval versus delayed crossover to chromium in the control sequence.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 1000 mcg/day
- Population
- Diabetic patients
- Participants
- 60
RCTEffect of chromium supplementation on blood glucose and lipid levels in type 2 diabetes mellitus elderly patients2004
In 39 elderly diabetic rehabilitation patients over 3 weeks, 400 µg/day chromium picolinate reduced fasting glucose, HbA1c, and total cholesterol versus baseline.
- Effect
- Benefit
- Duration
- 3 weeks
- Dose
- 400 mcg/day
- Population
- Older adults
- Avg age
- ~73
ObservationalLower toenail chromium in men with diabetes and cardiovascular disease compared with healthy men2004n=688
In 688 men, lower toenail chromium was associated with diabetes plus cardiovascular disease versus healthy controls in this observational cohort.
- Population
- Men
- Participants
- 688
- Ages
- 40–75
RCTRole of chromium supplementation in Indians with type 2 diabetes mellitus2002n=50
In 50 Indian type 2 diabetes patients over 12 weeks, 400 µg/day chromium picolinate improved fasting and postprandial glucose and HbA1c versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 400 mcg/day
- Population
- Diabetic patients
- Participants
- 50
RCTPotential antioxidant effects of zinc and chromium supplementation in people with type 2 diabetes mellitus2001
In Tunisian type 2 diabetes patients over 6 months, chromium, zinc, or combined supplementation reduced lipid peroxidation markers but did not change HbA1c or glucose.
- Effect
- No Benefit
- Duration
- 6 months
- Dose
- 400 μg/day
- Population
- Adults
RCTThe effects of inorganic chromium and brewer's yeast supplementation on glucose tolerance, serum lipids and drug dosage in individuals with type 2 diabetes2000
In 78 type 2 diabetes patients, brewer's yeast chromium improved glucose, fructosamine, triglycerides, and HDL more than inorganic chromium chloride over 8 weeks.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 200 μg/day
- Population
- Diabetic patients
Chromium supplementation for women with gestational diabetes mellitus1999
A pilot study suggested chromium supplementation improved glucose tolerance in women with gestational diabetes without adverse maternal or fetal outcomes.
- Effect
- Benefit
- Population
- Women
Case reportControl of steroid-induced diabetes with supplemental chromium1999
Case reports suggested supplemental chromium helped control hyperglycemia in patients with corticosteroid-induced diabetes.
- Population
- Patients with type 2 diabetes
Case reportReversal of corticosteroid-induced diabetes mellitus with supplemental chromium1999n=13
In 13 patients, corticosteroid treatment increased urinary chromium losses, and chromium picolinate 600 µg/day lowered fasting glucose in three patients with steroid-induced diabetes.
- Effect
- Benefit
- Dose
- 600 mcg/day
- Population
- Patients with type 2 diabetes
- Participants
- 13
RCTChromium picolinate supplementation for diabetes mellitus1998
A case report described HbA1c falling from 11.3% to 7.9% over 3 months after starting chromium picolinate 600 µg/day in a woman with type 1 diabetes.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 600 mcg/day
- Population
- Diabetic patients
Age-related decreases in chromium levels in 51,665 hair, sweat, and serum samples from 40,872 patients—implications for the prevention of cardiovascular disease and type II diabetes mellitus1997n=40,872
An analysis of 51,665 samples from 40,872 patients found chromium levels decline with age in hair, sweat, and serum, potentially linking age-related chromium loss to metabolic and cardiovascular risk.
- Effect
- No Benefit
- Population
- Patients with type 2 diabetes
- Participants
- 40,872
RCTElevated intakes of supplemental chromium improve glucose and insulin variables in individuals with type 2 diabetes1997n=180
In 180 type 2 diabetes patients over 4 months, 1,000 µg/day chromium picolinate significantly improved HbA1c, fasting and 2-hour glucose, insulin, and total cholesterol versus placebo.
- Effect
- Benefit
- Duration
- 4 months
- Dose
- 1000 mcg/day
- Population
- Adults
- Participants
- 180
RCTBeneficial effect of chromium supplementation on serum triglyceride levels in NIDDM1994n=30
In 30 non-insulin-dependent diabetes patients, chromium picolinate for 2 months significantly reduced serum triglycerides by 17.4% versus placebo without changing glucose or LDL/HDL.
- Effect
- Benefit
- Duration
- 2 months
- Population
- Patients with type 2 diabetes
- Participants
- 30
Controlled trialThe effects of chromium supplementation on serum glucose and lipids in patients with and without non-insulin-dependent diabetes1992n=76
In 76 patients with atherosclerotic disease over 7–16 months, 250 µg/day chromium chloride raised HDL and lowered triglycerides versus placebo without changing glucose or total cholesterol.
- Effect
- No Benefit
- Duration
- 7–16 months
- Dose
- 250 mcg/day
- Population
- Patients with type 2 diabetes
- Participants
- 76
Plasma chromium and chromium excretion in diabetes1985
This biochemical study reported altered plasma chromium levels and increased urinary chromium excretion in people with diabetes.
- Population
- Diabetic patients
L-CarnitineView supplement →
Consider purchase·★★★★★
How we scored this▸
- Taking L-carnitine supplements (from about 200 mg up to 4 grams daily) may help people with diabetes or obesity slightly lower blood sugar, insulin levels, and improve how their body responds to insulin.
- These benefits are generally seen when taking at least 2 grams per day for 3 months or more.
- However, the improvements are small and it’s unclear how much they help in real life.
- Some studies also show small benefits for cholesterol and weight, especially when L-carnitine is combined with weight-loss medications.
Browse 25 studies·6 meta-analyses
MetaThe effects of L-carnitine supplementation on cardiovascular risk factors in participants with impaired glucose tolerance and diabetes: a systematic review and dose-response meta-analysis2024n=2,900
A meta-analysis of 21 RCTs (2,900 participants) found L-carnitine significantly reduced triglycerides, LDL-C, fasting glucose, HbA1c, HOMA-IR, CRP, TNF-α, weight, BMI, body fat percentage, and leptin in diabetic or glucose-intolerant patients.
- Effect
- Benefit
- Population
- Children
- Participants
- 2,900
MetaEffects of L-carnitine supplementation on glucolipid metabolism: a systematic review and meta-analysis2023
A systematic review and meta-analysis found L-carnitine supplementation improved fasting glucose and insulin resistance markers in adults with metabolic disturbance.
- Effect
- Benefit
- Population
- Adults
Systematic reviewThe effects of L-carnitine supplementation on glycemic markers in adults: A systematic review and dose-response meta-analysis2023n=2,900
A systematic review and dose-response meta-analysis found L-carnitine supplementation significantly reduced fasting blood glucose, HbA1c, and HOMA-IR in adults versus controls.
- Effect
- Benefit
- Dose
- 2 g/day
- Population
- Adults
- Participants
- 2,900
RCTL-Carnitine as a Diet Supplement in Patients With Type II Diabetes2020n=97
In 181 Greek type 2 diabetes patients, 2 g/day oral L-carnitine improved glycemic control and reduced fatigue and insomnia versus baseline.
- Effect
- Benefit
- Dose
- 2 g/day
- Population
- Diabetic patients
- Participants
- 97
- Ages
- 50–65
RCTThe effects of L-carnitine supplementation on lipid concentrations in patients with type 2 diabetes: A systematic review and meta-analysis of randomized clinical trials2020
A meta-analysis of RCTs in type 2 diabetes found L-carnitine supplementation significantly reduced total cholesterol by 8.17 mg/dL versus placebo.
- Effect
- Benefit
- Dose
- 200 mg/day
- Population
- Diabetic patients
RCTThe effects of L-carnitine supplementation on glycemic control: a systematic review and meta-analysis of randomized controlled trials2019
A meta-analysis of 37 RCTs (44 effect sizes) found L-carnitine supplementation improved glycemic control markers versus placebo.
- Effect
- Benefit
RCTBlood Pressure and Metabolic Effects of Acetyl-L-Carnitine in Type 2 Diabetes: DIABASI Randomized Controlled Trial2018n=29
The DIABASI RCT in 229 hypertensive type 2 diabetes patients found acetyl-L-carnitine 1000 mg twice daily for 6 months did not improve blood pressure, glycemic control, lipids, or insulin sensitivity versus placebo on statin therapy.
- Effect
- No Benefit
- Duration
- 6 months
- Dose
- 1000 mg 2×/day
- Population
- Diabetic patients
- Participants
- 29
- Ages
- 40+
RCTComparative study to evaluate the effect of L-carnitine plus glimepiride versus glimepiride alone on insulin resistance in type 2 diabetic patients2018n=58
In 58 type 2 diabetes patients failing glimepiride monotherapy, adding 1 g L-carnitine twice daily to glimepiride for 6 months improved insulin resistance versus glimepiride alone.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 2 mg 2×/day
- Population
- Diabetic patients
- Participants
- 58
RCTEffects of L-carnitine supplementation on the quality of life in diabetic patients with muscle cramps2018n=91
In 25 diabetic patients with muscle cramps, 4 months of L-carnitine 600 mg/day reduced cramp frequency and pain scores and improved quality-of-life subscales for body pain, vitality, and social function.
- Effect
- Benefit
- Duration
- 4 months
- Dose
- 600 mg/day
- Population
- Diabetic patients
- Participants
- 91
RCTEffects of acetyl-L-carnitine and methylcobalamin for diabetic peripheral neuropathy: A multicenter, randomized, double-blind, controlled trial2016n=232
In 232 diabetic peripheral neuropathy patients, 500 mg acetyl-L-carnitine three times daily for 24 weeks was non-inferior to methylcobalamin for neuropathy symptoms and nerve conduction.
- Effect
- Benefit
- Duration
- 24 weeks
- Dose
- 500 mg 3×/day
- Population
- Diabetic patients
- Participants
- 232
- Ages
- 18–70
RCTEvaluation of L-Carnitine Efficacy in the Treatment of Non-Alcoholic Fatty Liver Disease among Diabetic Patients: A Randomized Double Blind Pilot Study2016
A randomized double-blind pilot study in diabetic patients with NAFLD reported L-carnitine improved liver enzymes and reduced hepatic fat accumulation versus placebo.
- Effect
- Benefit
- Population
- Diabetic patients
RCTEffect of carnitine-orotate complex on glucose metabolism and fatty liver: a double-blind, placebo-controlled study2014n=26
In 52 drug-naïve patients with impaired glucose metabolism and fatty liver, carnitine-orotate 250 mg three times daily plus metformin for 12 weeks improved glucose metabolism and fatty liver versus metformin alone.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 250 mg 3×/day
- Population
- Adults with impaired glucose metabolism
- Participants
- 26
MetaMetabolic effects of L-carnitine on type 2 diabetes mellitus: systematic review and meta-analysis2013n=284
A meta-analysis of RCTs (284 participants) in type 2 diabetes found L-carnitine improved metabolic parameters including lipid and glycemic markers versus control.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 284
RCTComparison between orlistat plus L-carnitine and orlistat alone on inflammation parameters in obese diabetic patients2011n=58
In 258 obese type 2 diabetic patients, 1 year of orlistat plus L-carnitine 2 g/day improved body weight, glycemic control, LDL, adiponectin, and inflammatory markers more than orlistat alone.
- Effect
- Benefit
- Duration
- 1 year
- Dose
- 120 mg 3×/day
- Population
- Diabetic patients
- Participants
- 58
RCTEffects of combination of sibutramine and L-carnitine compared with sibutramine monotherapy on inflammatory parameters in diabetic patients2011
In 254 obese type 2 diabetic patients, 12 months of sibutramine plus L-carnitine 2 g/day improved body weight, HbA1c, insulin resistance, and inflammatory markers faster than sibutramine alone.
- Effect
- Benefit
- Duration
- 12 months
- Dose
- 2 g/day
- Population
- Diabetic patients
RCTCaloric restriction and L-carnitine administration improves insulin sensitivity in patients with impaired glucose metabolism2010n=8
In adults with impaired fasting glucose or type 2 diabetes, 2 g L-carnitine twice daily for 10 days with caloric restriction did not clearly improve insulin sensitivity versus control.
- Effect
- No Benefit
- Duration
- 10 days
- Dose
- 2 g 2×/day
- Population
- Adults
- Participants
- 8
RCTOrlistat and L-carnitine compared to orlistat alone on insulin resistance in obese diabetic patients2010n=58
In 258 obese type 2 diabetic patients, 1 year of orlistat plus L-carnitine 2 g/day produced faster improvements in body weight, HbA1c, insulin resistance, and inflammatory markers than orlistat monotherapy.
- Effect
- Benefit
- Duration
- 12 months
- Dose
- 120 mg 3×/day
- Population
- Diabetic patients
- Participants
- 58
RCTEffect of L-carnitine on the size of low-density lipoprotein particles in type 2 diabetes mellitus patients treated with simvastatin2009n=40
In 80 diabetic patients on simvastatin 20 mg, adding 2 g/day L-carnitine for 3 months increased LDL particle size versus simvastatin alone.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 2 g/day
- Population
- Diabetic patients
- Participants
- 40
RCTEffects of simvastatin and carnitine versus simvastatin on lipoprotein(a) and apoprotein(a) in type 2 diabetes mellitus2009n=75
In 75 type 2 diabetes patients, simvastatin plus L-carnitine for 4 months lowered Lp(a) and Apo(a) more than simvastatin alone.
- Effect
- Benefit
- Duration
- 4 months
- Population
- Diabetic patients
- Participants
- 75
RCTL-Carnitine supplementation reduces oxidized LDL cholesterol in patients with diabetes2009n=41
In 81 type 2 diabetes patients, 2 g/day L-carnitine for 3 months reduced oxidized LDL cholesterol versus placebo.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 2 g/day
- Population
- Diabetic patients
- Participants
- 41
RCTEffect of oral L-carnitine administration on insulin sensitivity and lipid profile in type 2 diabetes mellitus patients2008n=12
In 12 type 2 diabetes patients, 2 g/day L-carnitine (1 g three times daily) for 4 weeks improved insulin sensitivity versus placebo.
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 2 g/day
- Population
- Diabetic patients
- Participants
- 12
RCTL-Carnitine supplementation reduces oxidized LDL cholesterol in patients with diabetes2008n=41
In 81 type 2 diabetes patients, 2 g/day L-carnitine for 3 months reduced oxidized LDL cholesterol versus placebo.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 2 g/day
- Population
- Diabetic patients
- Participants
- 41
RCTEffect of L-carnitine on plasma glycemic and lipidemic profile in patients with type II diabetes mellitus2005
In 35 type 2 diabetes patients, 1 g L-carnitine three times daily for 12 weeks decreased fasting glucose and improved lipid parameters versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 2 g/day
- Population
- Diabetic patients
- Avg age
- ~51±3.7
RCTThe effect of L-carnitine on plasma lipoprotein(a) levels in hypercholesterolemic patients with type 2 diabetes mellitus2003n=94
In 94 hypercholesterolemic patients, L-carnitine for 6 months reduced lipoprotein(a) levels versus baseline in a randomized trial.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 2 g/day
- Population
- Diabetic patients
- Participants
- 94
- Avg age
- ~51
RCTThe effects of oral L-carnitine treatment on blood lipid metabolism and the body fat content in the diabetic patient1998n=46
In 46 non-insulin-dependent diabetes patients, 3 g/day L-carnitine for 12 weeks significantly reduced blood lipids and body fat content versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 3 g/day
- Population
- Diabetic patients
- Participants
- 46
MagnesiumView supplement →
Consider purchase·★★★★★
How we scored this▸
- Eating more magnesium in your diet is linked to better blood sugar control and a lower chance of developing type 2 diabetes in adults and overweight children.
- About 25 to 38 out of every 100 people with type 2 diabetes have low magnesium, especially if their diabetes is not well managed.
- People with diabetes who eat less than 250 mg of magnesium daily have a 56% higher risk of dying, especially if their blood sugar levels are high.
- Some studies show that taking magnesium supplements can help lower blood sugar and improve insulin use in people with low magnesium, but results vary.
- The benefits depend on the amount and type of magnesium and your initial magnesium levels.
Browse 21 studies·9 meta-analyses
RCTOral magnesium supplementation does not affect insulin sensitivity in people with insulin-treated type 2 diabetes and a low serum magnesium: a randomised controlled trial2024n=14
In a crossover RCT of 14 adults with insulin-treated type 2 diabetes and low serum magnesium, oral magnesium 15 mmol/day for 6 weeks raised serum magnesium modestly but did not improve insulin sensitivity versus placebo.
- Effect
- No Benefit
- Duration
- 6 weeks
- Dose
- 15 mmol/day
- Population
- Women
- Participants
- 14
- Ages
- 18+
ObservationalAssociation of dietary magnesium intake and glycohemoglobin with mortality risk in diabetic patients2022n=223
A study of 2,045 adults with diabetes divided by glycohemoglobin (HbA1c ≥ 7% and <7%) and daily dietary magnesium intake (> 250 mg/day and ≤ 250 mg/day) found a 56% increased risk of all-cause mortality in adults with lower dietary magnesium intake (≤250mg/day) and an 86% increased risk of all-cause mortality in individuals with poorly controlled diabetes (HbA1c ≥7.0%).
- Effect
- Benefit
- Duration
- 77 months
- Dose
- 250 mg/day
- Population
- Adults
- Participants
- 223
- Avg age
- 52.9±10.1
ObservationalChanges in Dietary Magnesium Intake and Risk of Type 2 Diabetes Mellitus in Middle School Students: Using Data from the HEALTHY Study2021
A study of 2,181 at-risk adolescents found increasing dietary magnesium intake from 6th to 8th grade negatively associated with BMI percentile change in both intervention and control schools.
- Effect
- Benefit
- Population
- Children/adolescents
- Ages
- 11.3–13.7
MetaOral Magnesium Supplementation for Treating Glucose Metabolism Parameters in People with or at Risk of Diabetes: A Systematic Review and Meta-Analysis of Double-Blind Randomized Controlled Trials2021
A meta-analysis of double-blind RCTs found magnesium supplementation reduced fasting glucose in type 2 diabetes and improved 2-hour OGTT glucose and insulin sensitivity markers in people at high diabetes risk.
- Effect
- Benefit
- Population
- Diabetic patients
MetaAssociation of magnesium intake with type 2 diabetes and total stroke: an updated systematic review and meta-analysis2020
A meta-analysis of 41 studies (53 cohorts) found higher magnesium intake associated with 22% lower type 2 diabetes risk and reduced total stroke risk in a dose-dependent manner.
- Effect
- Benefit
RCTThe Effects of Oral Magnesium Supplementation on Glycemic Response among Type 2 Diabetes Patients2018n=48
A 3-month RCT of 42 type 2 diabetes patients found 250 mg/day elemental magnesium significantly improved HbA1c (8.32% to 7.96%), fasting glucose, and HOMA-IR vs placebo.
- Effect
- Benefit
- Dose
- 250 mg/day
- Population
- Diabetic patients
- Participants
- 48
- Ages
- 35–60
RCTEfficacy of Magnesium Supplementation on Glycemic Control in Type 2 Diabetes Patients: A Meta-analysis2017
A meta-analysis of 7 RCTs found magnesium supplementation trended toward lower fasting glucose in type 2 diabetes (mean difference −0.19 mmol/L) but did not support routine magnesium for glycemic control.
- Effect
- No Benefit
- Population
- Diabetic patients
MetaDose-Response Relationship between Dietary Magnesium Intake and Risk of Type 2 Diabetes Mellitus: A Systematic Review and Meta-Regression Analysis of Prospective Cohort Studies2016n=637,922
A meta-regression analysis demonstrating a clear dose-response inverse relationship between dietary magnesium intake and risk of developing type 2 diabetes. A meta-analysis of 25 studies including 637,922 individuals with 26,828 cases of type 2 diabetes found that type 2 diabetes incidence was reduced by 8% to 13% for each 100 mg/day increase in magnesium intake after controlling for age and BMI. When compared with the lowest magnesium consumption group, there was a 17% reduction in risk of type 2 diabetes; 19% in women and 16% in men. This study primarily included US (16 studies) and Asian (7
- Effect
- Benefit
- Dose
- 100 mg/day
- Population
- Adults
- Participants
- 637,922
MetaNonlinear Reduction in Risk for Type 2 Diabetes by Magnesium Intake: An Updated Meta-Analysis of Prospective Cohort Studies2015n=539,735
An updated meta-analysis of 15 prospective cohorts (539,735 participants) found each 100 mg/day magnesium intake associated with 16% lower type 2 diabetes risk, with a nonlinear dose-response.
- Effect
- Benefit
- Dose
- 100 mg/day
- Participants
- 539,735
MetaDietary calcium intake and risk of type 2 diabetes: possible confounding by magnesium2012n=264,268
A cohort analysis suggesting that previously observed associations between higher calcium intake and lower diabetes risk may be confounded by magnesium intake. A meta-analysis of 6 cohort studies including 264,268 participants and 11125 cases found that when failing to control for magnesium as a confounder, dietary calcium intake was associated with a 15% reduction in type 2 diabetes risk (RR 0.85, 95% CI 0.85-0.97) however no significant reduction was found when controlling for magnesium. This suggests that many studies linking calcium to reduced type 2 diabetes risk are confounded by magnesi
- Participants
- 264,268
MetaMagnesium intake and risk of type 2 diabetes: meta-analysis of prospective cohort studies2011n=536,318
A meta-analysis of prospective cohorts showing that higher dietary magnesium intake is associated with significantly reduced risk of developing type 2 diabetes. A meta-analysis of 13 prospective cohort studies including 536,318 participants and 24,516 cases found that each 100 mg/day increase in magnesium led to a 14% reduction in type 2 diabetes risk (RR 0.76, 95% CI 0.82-0.89, I2 = 48.4%). There was a significant inverse relationship between the highest and lowest magnesium intake and risk of type 2 diabetes in 9 of 13 studies (RR 0.78, 95% CI 0.73-0.84).
- Effect
- Benefit
- Dose
- 100 mg/day
- Participants
- 536,318
MetaMagnesium intake and risk of type 2 diabetes: a meta-analysis2007n=286,668
A meta-analysis demonstrating that higher magnesium intake is consistently linked to reduced incidence of type 2 diabetes across multiple prospective studies. A meta-analysis of 7 prospective cohort studies including 286,668 participants and 10,912 type 2 diabetes cases found a 15% reduction in diabetes risk from a 100 mg/day increase in dietary or supplemental magnesium intake. Both dietary magnesium and dietary + supplement magnesium showed a similar reduction in risk.
- Effect
- Benefit
- Dose
- 100 mg/day
- Participants
- 286,668
MetaEffects of oral magnesium supplementation on glycaemic control in Type 2 diabetes: a meta-analysis of randomized double-blind controlled trials2006n=370
A meta-analysis of 9 double-blind RCTs (370 type 2 diabetes patients, 360 mg/day for 4–16 weeks) found magnesium reduced fasting glucose by 0.56 mmol/L and raised HDL cholesterol by 0.08 mmol/L vs placebo.
- Effect
- Benefit
- Duration
- 4–16 weeks
- Dose
- 360 mg/day
- Population
- Diabetic patients
- Participants
- 370
Magnesium deficiency is associated with insulin resistance in obese children2005
A study of 48 children (24 obese nondiabetic BMI >= 85th percentile + 24 lean control subjects BMI < 85th percentile) found an inverse correlation between serum magnesium and fasting insulin, and positive correlation between serum magnesium and quantitative insulin sensitivity check index (QUICKI). Obese subjects: Had significantly lower serum magnesium (0.748 +/- 0.015 mmol/l) vs. lean children (0.801 +/- 0.012 mmol/l) Had significantly lower dietary magnesium intake (0.12 +/- 0.004 mg/kcal) vs lean children (0.14 +/- 0.004 mg/kcal) Improved magnesium status is associated with leanness
- Effect
- Benefit
- Dose
- 0.004 mg/day
- Population
- Adults
Clinical efficacy of magnesium supplementation in patients with type 2 diabetes2004
A 30-day study of 9 mild type 2 diabetes patients given magnesium-rich water (300 mL/day) found reduced insulin, HOMA-IR, triglycerides, and blood pressure vs baseline.
- Effect
- Benefit
- Duration
- 30 days
- Dose
- 300 mL/day
- Population
- Diabetic patients
RCTOral magnesium supplementation improves insulin sensitivity and metabolic control in type 2 diabetic subjects: a randomized double-blind controlled trial2003n=63
A 16-week double-blind RCT of 63 type 2 diabetes patients with low magnesium found 50 mL/day MgCl2 improved fasting glucose (8.0 vs 10.3 mmol/L), HbA1c (8.0% vs 10.1%), and HOMA-IR vs placebo.
- Effect
- Benefit
- Duration
- 16 weeks
- Dose
- 50 ml/day magnesium chloride solution
- Population
- Diabetic patients
- Participants
- 63
RCTOral magnesium supplementation in insulin-requiring Type 2 diabetihttps://journals.lww.com/ajg/citation/2000/09000/A_comparison_of_famotidine_antacid_combination.212.aspxc patients1998n=34
A 3-month RCT of 50 insulin-treated type 2 diabetes patients found 15 mmol/day magnesium raised plasma magnesium and urinary excretion but did not significantly change HbA1c, glucose, lipids, or blood pressure vs placebo.
- Effect
- No Benefit
- Duration
- 3 months
- Population
- Diabetic patients
- Participants
- 34
RCTThe effect of magnesium supplementation in increasing doses on the control of type 2 diabetes1998n=128
A 30-day dose-escalation RCT of 128 type 2 diabetes patients found only the highest dose (41.4 mmol/day MgO) reduced fructosamine, with no glycemic benefit at lower doses.
- Effect
- Benefit
- Duration
- 30 days
- Population
- Diabetic patients
- Participants
- 128
- Ages
- 30–69
RCTHypomagnesemia in type II diabetes: effect of a 3-month replacement therapy1995n=40
A 3-month double-blind RCT of 40 hypomagnesemic type 2 diabetes patients found 30 mmol/day magnesium corrected low magnesium levels but did not change HbA1c (7.2% vs 7.4%).
- Effect
- No Benefit
- Duration
- 3 months
- Population
- Diabetic patients
- Participants
- 40
RCTEffect of magnesium treatment on glycemic control and metabolic parameters in NIDDM patients1994
A clinical trial in NIDDM patients reported that magnesium treatment improved glycemic control and metabolic parameters, though full abstract details were unavailable.
- Effect
- Benefit
RCTDaily magnesium supplements improve glucose handling in elderly subjects1992
A 4-week crossover RCT in elderly subjects found daily magnesium supplementation improved insulin response and glucose tolerance during intravenous glucose tolerance testing.
- Effect
- Benefit
- Duration
- 4 weeks
- Dose
- 0.33 g/kg
- Population
- Older adults
- Avg age
- ~78
OatsView supplement →
Consider purchase·★★★★★
How we scored this▸
- Eating whole grains like oats may help lower the risk of developing type 2 diabetes and improve blood sugar control in people with diabetes.
- Studies show that each 16-gram serving of whole grains lowers diabetes risk by about 7% to 11%.
- Eating oats and oat bran for a few weeks or months can reduce blood sugar, insulin, and bad cholesterol levels, especially when eating less-processed oats like thick-cut or whole kernels.
- In people with type 2 diabetes, eating 50 to 100 grams of oats daily helps lower blood sugar levels after meals and improves long-term blood sugar control.
- Oats may also help kids with type 1 diabetes and pregnant women with gestational diabetes control their blood sugar better.
Browse 11 studies·2 meta-analyses
RCTOat beta-glucans consumed at breakfast improve glucose tolerance acutely and after a subsequent lunch - a randomized dose-response study in healthy young adults2025n=19
In 19 healthy adults, 2–4 g oat beta-glucan with 30 g available carbohydrate reduced postprandial glucose peak and improved glycemia after a subsequent lunch vs reference drink.
- Effect
- Benefit
- Duration
- Acute (postprandial)
- Dose
- 2–4 g/day oat beta-glucan
- Population
- Healthy adults
- Participants
- 19
MetaA Systematic Review and Meta-Analysis of Randomized Controlled Trials on the Effects of Oats and Oat Processing on Postprandial Blood Glucose and Insulin Responses2021
A meta-analysis found intact oat kernels and thick oat flakes significantly lowered postprandial glucose and insulin vs refined grains; thin/instant flakes showed weaker effects.
- Effect
- Benefit
- Population
- Adults
RCTThe effect of oat bran consumption on gestational diabetes: a randomized controlled clinical trial2021n=112
In 112 women with gestational diabetes, adding 30 g/day oat bran to a GDM diet for 4 weeks lowered fasting and 2-hour postprandial glucose vs diet alone.
- Effect
- Benefit
- Duration
- 4 weeks
- Dose
- 30 g/day oat bran
- Population
- Pregnant women with gestational diabetes
- Participants
- 112
- Ages
- 18–35
Clinical trialThe effect of beta-glucan supplementation on glycemic control and variability in adolescents with type 1 diabetes mellitus2020n=30
In 30 adolescents with type 1 diabetes, 6 g/day oat beta-glucan for 1 week lowered mean, premeal/postmeal, and peak glucose and reduced glycemic variability (SD, CV, LBGI, CONGA) versus lower doses.
- Effect
- Benefit
- Duration
- 1 week
- Dose
- 3 g/day beta-glucan
- Population
- Children/adolescents
- Participants
- 30
ObservationalHigher Whole-Grain Intake Is Associated with Lower Risk of Type 2 Diabetes among Middle-Aged Men and Women: The Danish Diet, Cancer, and Health Cohort2018n=55,465
In 55,465 Danish adults, each 16 g/day whole-grain increment was associated with 11% (men) and 7% (women) lower type 2 diabetes risk; oats contributed to whole-grain intake.
- Effect
- Benefit
- Duration
- 15 years (median follow-up)
- Dose
- per 16 g/day whole-grain serving
- Population
- Adults
- Participants
- 55,465
- Ages
- 50–65
RCTShort- and Long-Term Effects of Wholegrain Oat Intake on Weight Management and Glucolipid Metabolism in Overweight Type-2 Diabetics: A Randomized Control Trial2016n=80
In 298 overweight type 2 diabetic adults, 30-day centralized oat intake (50–100 g/day) improved fasting and postprandial glucose and lipids vs control diet in a randomized trial.
- Effect
- Benefit
- Duration
- 30 days
- Dose
- 50–100 g/day oats
- Population
- Adults
- Participants
- 80
MetaThe Metabolic Effects of Oats Intake in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis2015
A meta-analysis found oats intake in type 2 diabetes lowered HbA1c by 0.42%, fasting glucose by 0.39 mmol/L, total cholesterol by 0.49 mmol/L, and LDL by 0.29 mmol/L.
- Effect
- Benefit
- Population
- Diabetic patients
RCTBeneficial effects of high dietary fiber intake in patients with type 2 diabetes mellitus2000n=13
In 13 type 2 diabetic patients, a high-fiber diet (50 g/day, half soluble) for 6 weeks lowered preprandial glucose by 13 mg/dL vs a moderate-fiber ADA diet.
- Effect
- Benefit
- Duration
- 6 weeks
- Dose
- 50 g/day total fiber (high-fiber diet)
- Population
- Diabetic patients
- Participants
- 13
Narrative reviewThe role of viscous soluble fiber in the metabolic control of diabetes. A review with special emphasis on cereals rich in beta-glucan1997
A review concluded beta-glucan–rich oats and barley (≥3 g/day beta-glucan, ~10% in food) can reduce glycemic peaks by ~50% and lower LDL in diabetic individuals.
- Effect
- Benefit
- Dose
- ≥3 g/day beta-glucan
- Population
- Diabetic patients
RCTOat bran concentrate bread products improve long-term control of diabetes: a pilot study1996n=8
In 8 men with NIDDM, oat bran concentrate bread providing 9 g/day soluble fiber for 12 weeks improved long-term glycemic control and insulin profiles vs white bread periods.
- Effect
- Benefit
- Duration
- 12 weeks per arm (24-week crossover)
- Dose
- 9 g/day soluble fiber (oat bran concentrate bread)
- Population
- Diabetic patients
- Participants
- 8
- Avg age
- ~45
High beta-glucan oat bran and oat gum reduce postprandial blood glucose and insulin in subjects with and without type 2 diabetes1994
In subjects with and without type 2 diabetes, oat bran and oat gum meals lowered postprandial glucose and insulin excursions vs wheat farina control.
- Effect
- Benefit
- Duration
- Acute (3 h postprandial)
- Population
- Diabetic patients
Olive OilView supplement →
Consider purchase·★★★★★
How we scored this▸
- Eating more olive oil appears to lower the risk of developing type 2 diabetes and helps improve blood sugar control in people who already have it.
- Studies show that regular olive oil consumption for several years reduces diabetes risk by about 16% to 22%, especially when eating 1 to 1.5 tablespoons (15–20 grams) daily.
- People with type 2 diabetes who eat olive oil have lower long-term blood sugar (HbA1c) and fasting glucose levels.
- Some research shows fewer benefits, often because of differences in the type of olive oil used in studies.
- Overall, olive oil may be a helpful part of managing or preventing diabetes.
Browse 3 studies·3 meta-analyses
MetaEffect of olive oil consumption on cardiovascular disease, cancer, type 2 diabetes, and all-cause mortality: A systematic review and meta-analysis2022n=806,203
A meta-analysis of 806,203 participants found each olive oil increment associated with 16% lower cardiovascular disease risk and reduced all-cause mortality.
- Effect
- Benefit
- Dose
- 25 g/day
- Participants
- 806,203
MetaEffect of extra virgin olive oil consumption on glycemic control: A systematic review and meta-analysis2021n=633
A meta-analysis of 13 RCTs in 633 participants found extra virgin olive oil did not significantly change fasting glucose, insulin, HOMA-IR, or HbA1c versus control.
- Effect
- No Benefit
- Participants
- 633
MetaOlive oil in the prevention and management of type 2 diabetes mellitus: a systematic review and meta-analysis of cohort studies and intervention trials2017
A meta-analysis of 4 cohorts and 29 trials found highest olive oil intake linked to 16% lower type 2 diabetes risk and olive oil supplementation reduced HbA1c and fasting glucose in diabetic patients.
- Effect
- Benefit
- Population
- Patients with type 2 diabetes
ResveratrolView supplement →
Consider purchase·★★★★★
How we scored this▸
- Taking resveratrol might help lower blood sugar and improve insulin resistance in people with type 2 diabetes, especially at doses of 250 mg or more each day.
- The benefits seem better for those with poorly controlled diabetes or middle-aged adults.
- Resveratrol has little effect on blood pressure, cholesterol, or liver health.
- Higher doses of around 500 mg or more may work better.
- More research is needed to find the best dose and who benefits the most.
Browse 24 studies·19 meta-analyses
MetaThe efficacy of resveratrol supplementation on inflammation and oxidative stress in type-2 diabetes mellitus patients: randomized double-blind placebo meta-analysis2025n=533
In 48 nursing students on shift work, Rhodiola rosea did not significantly reduce mental or physical fatigue versus placebo over the study period.
- Effect
- No Benefit
- Population
- Diabetic patients
- Participants
- 533
MetaResveratrol may mildly improve renal function in the general adult population: A systematic review and meta-analysis of randomized controlled clinical trials2023
A meta-analysis found resveratrol supplementation produced small improvements in estimated glomerular filtration rate versus placebo in general adult populations.
- Effect
- Benefit
- Dose
- 500 mg/day
- Population
- Adults
MetaEffects of Resveratrol on Metabolic Indicators in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis2022n=1,151
In 30 adults, Rhodiola rosea or ADAPT-232 reduced ultra-weak photon emission versus placebo, suggesting adaptogen-related biophysical effects in this pilot.
- Effect
- Benefit
- Dose
- 1000 mg/day
- Population
- Diabetic patients
- Participants
- 1,151
MetaInfluence of Age and Dose on the Effect of Resveratrol for Glycemic Control in Type 2 Diabetes Mellitus: Systematic Review and Meta-Analysis2022n=60
In 60 adults with stress-related fatigue, SHR-5 Rhodiola rosea 4 tablets daily improved fatigue, cognition, and stress symptoms versus placebo.
- Effect
- Benefit
- Dose
- 250 mg/day
- Population
- Adults
- Participants
- 60
- Ages
- 60+
MetaResveratrol supplementation efficiently improves endothelial health: A systematic review and meta-analysis of randomized controlled trials2022
A meta-analysis of RCTs found resveratrol supplementation significantly improved flow-mediated dilation and lowered ICAM-1 versus placebo in adults with cardiometabolic risk.
- Effect
- Benefit
- Population
- Patients with cardiovascular diseases
MetaThe effects of resveratrol on glycemic control and cardiometabolic parameters in patients with T2DM: A systematic review and meta-analysis2022n=871
In foreign students, the adaptogen preparation rodakson based on Rhodiola rosea improved work capacity, coordination, and reduced fatigue versus baseline.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 871
MetaFine wine or sour grapes? A systematic review and meta-analysis of the impact of red wine polyphenols on vascular health2021
A meta-analysis found red wine polyphenols and resveratrol improved some vascular function measures in human trials, though effects were modest.
- Effect
- Benefit
- Population
- Healthy adults
MetaResveratrol supplementation and type 2 diabetes: a systematic review and meta-analysis2021n=10
In 10 adults with generalized anxiety disorder, Rhodiola rosea (Rhodax) reduced Hamilton Anxiety scores versus baseline in this open-label pilot study.
- Effect
- Benefit
- Population
- Adults
- Participants
- 10
MetaThe effects of resveratrol on glycemic control and cardiometabolic parameters in patients with T2DM: A systematic review and meta-analysis2021n=871
In foreign students, the adaptogen preparation rodakson based on Rhodiola rosea improved work capacity, coordination, and reduced fatigue versus baseline.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 871
MetaThe effects of resveratrol supplementation in patients with type 2 diabetes, metabolic syndrome, and nonalcoholic fatty liver disease: an umbrella review of meta-analyses of randomized controlled trials2021n=6
An overview of meta-analyses found resveratrol produced small improvements in some cardiometabolic markers in T2DM, MetS, and NAFLD, with low certainty for many outcomes.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 6
MetaThe effects of resveratrol on lipid profiles and liver enzymes in patients with metabolic syndrome and related disorders: a systematic review and meta-analysis of randomized controlled trials2020
A meta-analysis in metabolic syndrome patients found resveratrol improved some lipid profiles and liver enzymes, though results varied by outcome.
- Effect
- Benefit
- Population
- Patients with metabolic syndrome
MetaCan resveratrol supplement change inflammatory mediators? A systematic review and meta-analysis on randomized clinical trials2019n=658
A meta-analysis of RCTs (658 participants) found resveratrol significantly lowered CRP and TNF-α but not IL-6 versus placebo.
- Effect
- Benefit
- Population
- Adults
- Participants
- 658
- Ages
- 18–75
MetaEffect of Resveratrol on Blood Lipid Levels in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis2019n=363
In 220 menopausal women, a black cohosh plus Rhodiola combination reduced Kupperman menopausal scores more than black cohosh alone or placebo over 12 weeks.
- Effect
- Benefit
- Duration
- 12 weeks
- Population
- Diabetic patients
- Participants
- 363
RCTResveratrol reduces albuminuria in diabetic nephropathy: A randomized double-blind placebo-controlled clinical trial2019n=60
In 60 type 2 diabetic patients with albuminuria, resveratrol 500 mg/day for 90 days reduced urinary albumin/creatinine ratio versus placebo alongside losartan.
- Effect
- Benefit
- Duration
- 90 days
- Dose
- 500 mg/day
- Population
- Diabetic patients
- Participants
- 60
MetaResveratrol supplementation significantly influences obesity measures: a systematic review and dose-response meta-analysis of randomized controlled trials2019
A meta-analysis of 28 trials found resveratrol significantly reduced body weight and BMI in adults, with larger effects at higher doses.
- Effect
- Benefit
- Dose
- 500 mg/day
- Population
- Adults
MetaThe Effects of Resveratrol Supplementation on Endothelial Function and Blood Pressures Among Patients with Metabolic Syndrome and Related Disorders: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2019
A meta-analysis in metabolic syndrome found resveratrol improved endothelial function in some trials but did not consistently lower blood pressure versus placebo.
- Effect
- Benefit
- Population
- Patients with metabolic syndrome
MetaEvidence-based nutritional and pharmacological interventions targeting chronic low-grade inflammation in middle-age and older adults: A systematic review and meta-analysis2018
An umbrella meta-analysis in middle-age and older adults found resveratrol modestly lowered IL-6 and CRP among anti-inflammatory interventions for chronic low-grade inflammation.
- Effect
- Benefit
- Dose
- 0.17 mg/day
- Population
- Older adults
MetaThe effects of resveratrol supplementation on biomarkers of inflammation and oxidative stress among patients with metabolic syndrome and related disorders: a systematic review and meta-analysis of randomized controlled trials2018
A meta-analysis found resveratrol reduced inflammatory and oxidative stress biomarkers in metabolic syndrome patients, though heterogeneity was high.
- Effect
- Benefit
- Population
- Patients with metabolic syndrome
RCTResveratrol as Add-on Therapy in Subjects With Well-Controlled Type 2 Diabetes: A Randomized Controlled Trial2016n=15
In 15 volunteers at simulated 4600 m altitude, 7-day Rhodiola rosea did not improve capillary oxygenation versus placebo or oxygenated water.
- Effect
- No Benefit
- Duration
- 30 days
- Dose
- 150 mg/day
- Population
- Patients with type 2 diabetes
- Participants
- 15
RCTSix months of resveratrol supplementation has no measurable effect in type 2 diabetic patients. A randomized, double blind, placebo-controlled trial2016
In endurance athletes, Rhodiola rosea supplementation did not reduce in vivo inflammatory activity after continuous exercise versus control.
- Effect
- No Benefit
- Duration
- 6 months
- Dose
- 40 mg/day
- Population
- Diabetic patients
MetaResveratrol treatment as an adjunct to pharmacological management in type 2 diabetes mellitus--systematic review and meta-analysis2015
In endurance athletes, Rhodiola rosea did not reduce in vivo inflammatory activity after continuous exercise compared with control conditions.
- Effect
- No Benefit
- Population
- Athletes
MetaEffect of resveratrol on glucose control and insulin sensitivity: a meta-analysis of 11 randomized controlled trials2014n=388
A meta-analysis of 11 RCTs (388 participants) found resveratrol did not significantly improve fasting glucose or insulin sensitivity overall versus placebo.
- Effect
- No Benefit
- Participants
- 388
RCTPilot study of resveratrol in older adults with impaired glucose tolerance2012n=10
In marathon runners, Rhodiola rosea before a race did not significantly reduce muscle damage, DOMS, or cytokines versus placebo.
- Effect
- No Benefit
- Duration
- 4 weeks
- Dose
- 2 g/day
- Population
- Older adults
- Participants
- 10
- Avg age
- ~72
RCTResveratrol improves insulin sensitivity, reduces oxidative stress and activates the Akt pathway in type 2 diabetic patients2011
In healthy volunteers after exhaustive exercise, Rhodiola rosea reduced C-reactive protein and creatine kinase elevations versus control.
- Effect
- Benefit
- Dose
- 10 mg/day resveratrol
- Population
- Diabetic patients
Beta-AlanineView supplement →
Consider purchase·★★★★★
How we scored this▸
- Research shows that taking supplements containing carnosine or its precursor beta-alanine can help improve blood sugar and insulin levels in people with diabetes or prediabetes.
- Studies found that these supplements slightly lower fasting blood sugar, long-term blood sugar control (HbA1c), and improve how the body responds to insulin.
- More research is needed to determine the ideal dose and who might benefit the most.
Browse 1 study·1 meta-analysis
MetaEffect of Carnosine or β-Alanine Supplementation on Markers of Glycemic Control and Insulin Resistance in Humans and Animals: A Systematic Review and Meta-analysis2021n=16
A systematic review and meta-analysis of 20 human and rodent studies found carnosine or beta-alanine supplementation reduced fasting glucose, HbA1c, HOMA-IR, and fasting insulin in humans (moderate certainty).
- Effect
- Benefit
- Participants
- 16
ProbioticsView supplement →
Consider purchase·★★★★★
How we scored this▸
- Probiotics are possibly effective for Type 2 diabetes.
Browse 1 study·1 meta-analysis
MetaEffects of probiotics supplementation on glycemic profile in adults with type 2 diabetes mellitus: A grade-assessed systematic review and dose-response meta-analysis of randomized controlled trials2024
A GRADE meta-analysis of 32 type 2 diabetes RCTs found probiotics lowered fasting glucose −13.27 mg/dL, HbA1c −0.44%, insulin, and HOMA-IR versus control.
- Effect
- Benefit
- Population
- Adults
Ivy GourdView supplement →
Consider purchase·★★★★★
How we scored this▸
- Early research shows that taking 20 grams of ivy gourd leaves with breakfast helps lower blood sugar after meals.
- Taking ivy gourd twice a day for 6 weeks also improves how the body handles sugar.
- In people with type 2 diabetes, taking ivy gourd extract daily for 3 months lowers blood sugar levels, HbA1C, and insulin resistance better than a placebo, with no reported side effects.
Browse 4 studies
RCTEfficacy and safety of a herbal drug of Coccinia grandis (Linn.) Voigt in patients with type 2 diabetes mellitus: A double blind randomized placebo controlled clinical trial2021n=79
In 145 newly diagnosed type 2 diabetes patients, Coccinia grandis extract 500 mg/day for 3 months significantly lowered HbA1c and improved selected lipid markers versus placebo with good tolerability.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 500 mg/day
- Population
- Diabetic patients
- Participants
- 79
- Avg age
- 45±15
Clinical trialBlood sugar lowering effect of Coccinia grandis (L.) J. Voigt: path for a new drug for diabetes mellitus2011n=122
In 122 healthy volunteers, a breakfast containing 20 g Coccinia grandis leaves reduced postprandial blood glucose rise versus a coconut placebo meal over a glucose tolerance test.
- Effect
- Benefit
- Dose
- 20 g/day
- Population
- Healthy adults
- Participants
- 122
- Ages
- 18–55
RCTEffect of supplementation of Coccinia cordifolia extract on newly detected diabetic patients2008
In 60 newly diagnosed type 2 diabetes patients, Coccinia cordifolia extract 1 g/day for 90 days significantly lowered fasting, postprandial glucose, and A1C versus placebo alongside standard dietary advice.
- Effect
- Benefit
- Duration
- 90 days
- Dose
- 1 g/day
- Population
- Diabetic patients
- Ages
- 35–60
Treatment of diabetes mellitus with Coccinia indica.1980
A 1980 clinical study reported Coccinia indica as a traditional antidiabetic remedy in patients with diabetes mellitus, though detailed trial outcomes were not available in the indexed record.
- Population
- Diabetic patients
AloeView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Some studies have found that taking aloe supplements by mouth may help lower blood sugar and improve cholesterol in people with prediabetes or diabetes.
- On average, aloe may lower blood sugar by about 30–47 points and HbA1c by up to 1%.
- Some studies also show improvements in cholesterol and triglycerides.
- However, results are mixed because aloe was used in many different forms and doses, and several studies found no benefit at all.
Browse 11 studies·3 meta-analyses
MetaEffect of Aloe vera on glycaemic control in prediabetes and type 2 diabetes: a systematic review and meta-analysis2016n=470
Meta-analysis of 8 RCTs in 470 patients found Aloe vera improved fasting glucose in prediabetes and HbA1c in type 2 diabetes, though heterogeneity limits certainty and more standardized trials are needed.
- Effect
- Benefit
- Population
- Prediabetes and type 2 diabetes patients
- Participants
- 470
MetaEfficacy of Aloe Vera Supplementation on Prediabetes and Early Non-Treated Diabetic Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2016n=415
Meta-analysis of 5 RCTs in 415 patients found aloe vera lowered fasting glucose, HbA1c, triglycerides, total and LDL cholesterol, and raised HDL versus controls, with limited safety data.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 415
MetaReduction of Fasting Blood Glucose and Hemoglobin A1c Using Oral Aloe Vera: A Meta-Analysis2016n=283
Meta-analysis of 9 studies in 283 patients reported oral aloe vera reduced fasting glucose by 46.6 mg/dL and HbA1c by 1.05%, supporting possible glycemic benefit in prediabetes and diabetes.
- Effect
- Benefit
- Population
- Patients with type 2 diabetes
- Participants
- 283
RCTMetabolic effects of Aloe vera gel complex in obese prediabetes and early non-treated diabetic patients: randomized controlled trial2013n=136
In an RCT of 136 obese prediabetic or early untreated diabetic patients, Aloe QDM complex reduced body weight, body fat, and insulin resistance over 8 weeks, with fasting glucose tending to improve.
- Effect
- Benefit
- Duration
- 8 weeks
- Population
- Diabetic patients
- Participants
- 136
RCTAnti-hyperglycemic and anti-hypercholesterolemic effects of Aloe vera leaf gel in hyperlipidemic type 2 diabetic patients: a randomized double-blind placebo-controlled clinical trial2012n=30
In a 2-month double-blind RCT of 30 hyperlipidemic type 2 diabetic patients given 600 mg/day aloe gel, fasting glucose, HbA1c, total cholesterol, and LDL fell significantly versus placebo with no adverse effects.
- Effect
- Benefit
- Duration
- 2 months
- Dose
- 600 mg/day
- Population
- Diabetic patients
- Participants
- 30
- Ages
- 40–60
RCTA prospective, randomized clinical trial comparing topical Aloe vera with 0.1% triamcinolone acetonide in mild to moderate plaque psoriasis2010n=80
In an 8-week RCT of 80 mild-to-moderate psoriasis patients, topical Aloe vera reduced PASI scores slightly more than 0.1% triamcinolone, while quality-of-life gains were similar between groups.
- Duration
- 8 weeks
- Population
- Patients with psoriasis
- Participants
- 80
RCTA double-blind, placebo-controlled study of a commercial Aloe vera gel in the treatment of slight to moderate psoriasis vulgaris2005n=40
In a 4-week double-blind RCT of 40 plaque psoriasis patients, commercial preserved Aloe vera gel was modest and performed worse than placebo on erythema, infiltration, and desquamation scores.
- Duration
- 4 weeks
- Population
- Patients with psoriasis
- Participants
- 40
Systematic reviewAloe vera: a systematic review of its clinical effectiveness1999
Systematic review of 10 controlled trials suggested oral aloe may lower blood glucose and lipids, and topical aloe may help genital herpes and psoriasis, but overall evidence remained limited and inconclusive.
- Effect
- Benefit
- Population
- Diabetic patients
Clinical trialAntidiabetic activity of Aloe vera L. juice II. Clinical trial in diabetes mellitus patients in combination with glibenclamide1996
In diabetic patients unresponsive to glibenclamide alone, adding Aloe vera juice significantly lowered fasting glucose within 2 weeks and triglycerides within 4 weeks, with no kidney or liver toxicity.
- Effect
- Benefit
- Population
- Diabetic patients
Clinical trialAntidiabetic activity of Aloe vera L. juice. I. Clinical trial in new cases of diabetes mellitus1996
Clinical trial of Aloe vera juice (1 tablespoon twice daily for at least 2 weeks) in diabetic patients reported lower blood sugar and triglycerides, suggesting potential antidiabetic activity without cholesterol change.
- Effect
- Benefit
- Duration
- 2 weeks
- Population
- Diabetic patients
The hypoglycemic and hypolipidemic effects of Aloe vera in Thai diabetic patients1996
This thesis examined hypoglycemic and hypolipidemic effects of Aloe vera in Thai diabetic patients. Without abstract data, clinical benefit cannot be assessed from available metadata alone.
- Effect
- No Benefit
- Population
- Diabetic patients
Green TeaView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is still uncertain whether green tea helps prevent diabetes or improves blood sugar.
- Some studies suggest benefits.
- In Japan, people who drank six or more cups a day had about a one-third lower risk of type 2 diabetes, with stronger effects seen in women.
- In China, drinking green tea at least once a week was linked with a much lower chance of developing high blood sugar.
- Another study showed that people who drank tea daily had a slightly lower risk of diabetes overall.
- However, other research has found the opposite, with some studies suggesting that higher green tea intake may actually increase diabetes risk.
- When people with prediabetes or type 2 diabetes were given green tea or green tea extract for several weeks, results did not show improvements in blood sugar, long-term sugar control (HbA1c), insulin levels, or insulin sensitivity.
- Some studies that combine people with normal blood sugar and those with diabetes show very small improvements, but studies focusing on diabetes alone do not find clear benefits.
- Green tea seems more promising in other areas.
- Taking higher amounts over longer periods, especially in people who are overweight, has been linked with small reductions in blood fats such as triglycerides and total cholesterol, though not in LDL or HDL cholesterol.
- It may also help with small amounts of weight and body fat loss, but not with waist size.
- In people already living with type 2 diabetes, drinking green tea daily has been linked in large studies with lower risk of death, though it does not appear to protect against diabetes-related complications.
Browse 15 studies·6 meta-analyses
MetaThe effect of green tea on patients with type 2 diabetes mellitus: A meta-analysis2024n=722
A meta-analysis of 15 RCTs (722 type 2 diabetes patients) found green tea significantly improved fasting glucose and related metabolic markers versus control.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 722
MetaEffect of green tea on glycemic control in patients with type 2 diabetes mellitus: A systematic review and meta-analysis2021
A meta-analysis of RCTs in type 2 diabetes found green tea supplementation lowered fasting glucose, HbA1c, and insulin resistance markers versus control.
- Effect
- No Benefit
- Population
- Diabetic patients
ObservationalTea consumption and long-term risk of type 2 diabetes and diabetic complications: a cohort study of 0.5 million Chinese adults2021n=30,300
In 482,425 diabetes-free and 30,300 diabetic Chinese adults (ages 30–79), tea consumption was examined for long-term type 2 diabetes and complication risk.
- Effect
- Benefit
- Population
- Adults
- Participants
- 30,300
- Ages
- 30–79
ObservationalAdditive effects of green tea and coffee on all-cause mortality in patients with type 2 diabetes mellitus: the Fukuoka Diabetes Registry2020n=4,923
In 4,923 Japanese adults with type 2 diabetes followed ~5.3 years, combined high green tea and coffee intake was associated with lower all-cause mortality.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 4,923
- Ages
- 20+
MetaEffect of green tea extract on lipid profile in patients with type 2 diabetes mellitus: A systematic review and meta-analysis2020
A meta-analysis found green tea extract (~800 mg/day) significantly improved lipid profiles, including total cholesterol, in type 2 diabetes patients.
- Effect
- Benefit
- Dose
- 800 mg/day
- Population
- Diabetic patients
MetaEffect of Green Tea on Anthropometric Indices and Body Composition in Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis2020
A meta-analysis in type 2 diabetes found green tea produced small favorable effects on weight-related anthropometric indices and body composition.
- Effect
- Benefit
- Dose
- 800 mg/day
- Population
- Diabetic patients
ObservationalGreen tea consumption and risk of type 2 diabetes in Chinese adults: the Shanghai Women's Health Study and the Shanghai Men's Health Study2018n=67
In two Shanghai cohorts (>119,000 adults), regular green tea drinking was associated with lower incident type 2 diabetes over 5–10 years of follow-up.
- Effect
- No Benefit
- Population
- Adults
- Participants
- 67
- Ages
- 5–10
RCTAssociations of green tea and rock tea consumption with risk of impaired fasting glucose and impaired glucose tolerance in Chinese men and women2013n=4,808
In 4,808 Chinese adults, moderate green and rock tea consumption was associated with lower odds of impaired fasting glucose and impaired glucose tolerance.
- Effect
- Benefit
- Population
- Adults
- Participants
- 4,808
MetaEffect of green tea on glucose control and insulin sensitivity: a meta-analysis of 17 randomized controlled trials2013n=1,133
A meta-analysis of 17 RCTs (1,133 participants) found green tea modestly improved fasting glucose and insulin sensitivity versus control.
- Effect
- Benefit
- Participants
- 1,133
RCTEffectiveness of green tea in a randomized human cohort: relevance to diabetes and its complications2013
In a 14-week RCT, adults at risk of diabetes who drank 3 cups/day of Mauritian green tea showed improvements in waist-hip ratio, glucose, blood pressure, and ALT versus control.
- Effect
- Benefit
- Duration
- 14 weeks
- Population
- Adults
MetaEffects of green tea catechins with or without caffeine on glycemic control in adults: a meta-analysis of randomized controlled trials2013n=1,584
A meta-analysis of 1,584 adults found green tea catechins (~583 mg/day), with or without caffeine, improved fasting blood glucose versus control.
- Effect
- Benefit
- Dose
- 582.8 mg/day
- Population
- Adults
- Participants
- 1,584
RCTDoes supplementation with green tea extract improve insulin resistance in obese type 2 diabetics? A randomized, double-blind, and placebo-controlled clinical trial2011n=80
In 80 obese adults with type 2 diabetes, 16 weeks of decaffeinated green tea extract (856 mg EGCG/day) improved insulin resistance versus placebo.
- Effect
- No Benefit
- Duration
- 16 weeks
- Dose
- 856 mg/day
- Population
- Adults
- Participants
- 80
- Ages
- 20–65
RCTA catechin-rich beverage improves obesity and blood glucose control in patients with type 2 diabetes2009n=23
In 43 type 2 diabetes patients over 12 weeks, catechin-rich green tea (583 mg/day) reduced waist circumference and improved adiponectin and glycemic markers versus low-catechin control.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 582.8 mg/day
- Population
- Diabetic patients
- Participants
- 23
ObservationalThe relationship between green tea and total caffeine intake and risk for self-reported type 2 diabetes among Japanese adults2006n=231
In 17,413 Japanese adults aged 40–65 followed 5 years, ≥6 cups/day green tea (OR 0.67) and ≥3 cups/day coffee (OR 0.58) were inversely associated with self-reported type 2 diabetes; black or oolong tea were not.
- Effect
- Benefit
- Population
- Adults
- Participants
- 231
- Ages
- 40–65
RCTRandomized controlled trial for an effect of green tea consumption on insulin resistance and inflammation markers2005n=66
In 66 borderline or diabetic adults over 2 months, green tea extract (544 mg polyphenols/day) improved insulin resistance and inflammatory markers versus control.
- Effect
- Benefit
- Duration
- 2 months
- Dose
- 544 mg/day
- Population
- Patients with diabetes
- Participants
- 66
- Ages
- 32–73
Vitamin DView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Vitamin D has no meaningful benefit for Type 2 diabetes.
Browse 12 studies·7 meta-analyses
MetaVitamin D supplementation vs. placebo and incident type 2 diabetes in an ancillary study of the randomized Vitamin D and Omega-3 Trial2025n=911
In VITAL-T2D analysis of 22,220 adults, 2,000 IU/day vitamin D3 did not reduce incident type 2 diabetes versus placebo in a general older population.
- Effect
- No Benefit
- Dose
- 2000 IU/day
- Population
- Adults
- Participants
- 911
- Avg age
- ~67
RCTEffects of cholecalciferol supplementation on depressive symptoms, C-peptide, serotonin, and neurotrophin-3 in type 2 diabetes mellitus: A double-blind, randomized, placebo-controlled trial2024n=38
A 12-week RCT in 38 type 2 diabetes patients with depression found cholecalciferol 4,000 IU/day improved depressive symptoms and raised serotonin versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 4000 IU/day
- Population
- Diabetic patients
- Participants
- 38
MetaEfficacy of vitamin D supplementation on glycaemic control in type 2 diabetes: An updated systematic review and meta-analysis of randomized controlled trials2024n=2,982
An updated meta-analysis of 39 RCTs (2,982 type 2 diabetes patients) found vitamin D supplementation significantly reduced FBG, HbA1c, HOMA-IR, and fasting insulin versus control.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 2,982
MetaThe Effect of Vitamin D Supplementation on Glycemic Control and Cardiovascular Risk Factors in Type 2 Diabetes: An Updated Systematic Review and Meta-Analysis of Clinical Trials2024
A meta-analysis found vitamin D supplementation significantly reduced HbA1c, FBS, and LDL and raised HDL in type 2 diabetes patients versus control.
- Effect
- Benefit
- Dose
- 50000 IU/day
- Population
- Diabetic patients
MetaSerum and supplemental vitamin D levels and insulin resistance in T2DM populations: a meta-analysis and systematic review2023n=11,063
A meta-analysis of 11,063 participants found higher serum vitamin D associated with lower insulin resistance in observational studies; supplementation effects were inconsistent.
- Participants
- 11,063
MetaWhat is the impact of vitamin D supplementation on glycemic control in people with type-2 diabetes: a systematic review and meta-analysis of randomized controlled trails2023
A meta-analysis of 46 RCTs found vitamin D supplementation significantly reduced HbA1c in type 2 diabetes patients versus placebo.
- Effect
- Benefit
- Dose
- 5.02 mg/day
- Population
- Patients with type 2 diabetes
RCTVitamin D Supplementation for the Treatment of Depressive Symptoms in Women with Type 2 Diabetes: A Randomized Clinical Trial2022n=129
In 119 women with type 2 diabetes and depression given 5000 or 50,000 IU/week vitamin D for 6 months, both doses similarly improved CES-D scores over time.
- Effect
- No Benefit
- Duration
- 6 months
- Dose
- 50000 IU/day
- Population
- Women
- Participants
- 129
- Avg age
- ~50
RCTEffect of vitamin D supplementation on glycose homeostasis and islet function in vitamin D deficient or insufficient diabetes and prediabetes: a systematic review and meta-analysis2021n=569
A meta-analysis of diabetes and prediabetes RCTs found vitamin D improved fasting and postprandial glucose and reduced progression from prediabetes to diabetes in supplemented groups.
- Effect
- Benefit
- Participants
- 569
MetaEfficacy of vitamin D supplementation on glycemic control in type 2 diabetes patients: A meta-analysis of interventional studies2019
A meta-analysis of RCTs found vitamin D supplementation significantly reduced HbA1c and fasting glucose in type 2 diabetes patients versus control.
- Effect
- Benefit
- Population
- Diabetic patients
MetaVitamin D supplementation and glycemic control in type 2 diabetes patients: A systematic review and meta-analysis2017
A systematic review of RCTs found vitamin D supplementation associated with modest improvements in HbA1c and fasting glucose in type 2 diabetes patients.
- Effect
- Benefit
- Population
- Patients with type 2 diabetes
RCTA randomized, placebo-controlled trial of vitamin D supplementation to improve glycaemia in overweight and obese African Americans2012
A 12-week RCT in 89 overweight African Americans with prediabetes found 4,000 IU/day vitamin D3 did not improve insulin secretion or sensitivity versus placebo.
- Effect
- No Benefit
- Duration
- 3 months
- Dose
- 4000 IU/day
- Population
- Adults
The effect of vitamin D3 on insulin secretion and peripheral insulin sensitivity in type 2 diabetic patients2003n=10
A study in 10 women with type 2 diabetes found vitamin D3 1,332 IU/day improved first-phase insulin secretion and peripheral insulin sensitivity versus baseline.
- Effect
- Benefit
- Dose
- 332 IU/day
- Population
- Diabetic patients
- Participants
- 10
Yerba MateView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is not clear if drinking yerba mate helps people with type 2 diabetes.
- One study found that drinking yerba mate tea three times a day for 60 days lowered fasting blood sugar by 17% and average blood sugar (HbA1c) by 0.85%.
- But the study did not include a comparison group, so the results are uncertain.
Browse 1 study
RCTMate tea (Ilex paraguariensis) improves glycemic and lipid profiles of type 2 diabetes and pre-diabetes individuals: a pilot study2011n=58
In an RCT, 330 mL mate tea, 3×/day, for 60 days, mate tea consumption decreased significantly the levels of fasting glucose (25.0 mg/dL), glycated hemoglobin A(1c) (HbA(1c)) (0.85%), and low-density lipoprotein cholesterol (LDL-c) (13.5 mg/dL) of T2DM subjects (p < 0.05); however, it did not change the intake of total energy, protein,...
- Effect
- Benefit
- Duration
- 60 days
- Dose
- 330 mL mate tea, 3×/day
- Population
- Patients with T2DM or pre-diabetes
- Participants
- 58
Alpha-Lipoic AcidView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Research shows that alpha-lipoic acid supplements do not meaningfully improve blood sugar control or insulin sensitivity in people with type 2 diabetes.
- Some small studies found slight changes in blood sugar and weight, but these were too small to be important.
- ALA may help blood sugar slightly in pregnancy-related diabetes and improve heart function in some young people with type 1 diabetes, but more research is needed.
Browse 14 studies·1 meta-analysis
EFFECTS OF ALPHA-LIPOIC ACID ON GLYCEMIC STATUS IN 2 TYPE DIABETES PATIENTS WITH СHRONIC CORONARY SYNDROME2022n=80
A clinical study including 80 people with type 2 diabetes and coronary heart disease who suffered non-Q-myocardial infarction found that ALA (600 mg daily for 4 months) in addition to baseline therapy showed a moderate but significant effect on decreasing fasting glucose (-11.6%).
- Effect
- Benefit
- Duration
- 4 months
- Dose
- 600 mg/day
- Population
- Adults
- Participants
- 80
RCTEfficacy and safety of oral alpha-lipoic acid supplementation for type 2 diabetes management: a systematic review and dose-response meta-analysis of randomized trials2022n=1,035
A meta-analysis of 16 studies including 1035 patients found that ALA (200-1200 mg/day for up to 1 year) did not lead to clinically significant changes in glycemic control, triglycerides or body weight. Despite improvements in some health markers, these changes were below minimal clinically important difference thresholds for all outcomes.
- Effect
- No Benefit
- Dose
- 500 mg/day
- Population
- Adults
- Participants
- 1,035
Clinical trialEffect of alpha-lipoic acid supplementation on the lipid profile and lipid ratios in women with gestational diabetes mellitus: A clinical trial study2020n=30
8-week clinical trial in 60 gestational diabetes women given 100 mg/day ALA lowered triglycerides, TyG index, and atherogenic index versus placebo.
- Effect
- Benefit
- Dose
- 100 mg/day
- Population
- Women
- Participants
- 30
- Ages
- 18–40
RCTAlpha-lipoic acid improves subclinical left ventricular dysfunction in asymptomatic patients with type 1 diabetes2013n=15
A study including 30 type 1 diabetes patients (aged 10-14) given either insulin or insulin plus ALA found that the insulin + ALA group experienced significantly increased glutathione levels and decreased malondialdhyde, nitric oxide, TNF-alpha, Fas ligand, matrix metalloproteinase 2 and troponin-I levels compared to only insulin. Patients were given 300 mg ALA twice daily, leading to improved left ventricular systolic and diastolic function. ALA may reduce the risk of developing diabetic cardiomyopathy in patients with type 1 diabetes.
- Effect
- Benefit
- Dose
- 300 mg 2×/day
- Population
- Diabetic patients
- Participants
- 15
- Ages
- 10–14
RCTShort-term continuous subcutaneous insulin infusion combined with insulin sensitizers rosiglitazone, metformin, or antioxidant α-lipoic acid in patients with newly diagnosed type 2 diabetes mellitus2013n=60
3-month RCT in newly diagnosed type 2 diabetes found insulin infusion plus metformin or rosiglitazone beat insulin alone for glycemic remission; ALA add-on showed no extra benefit.
- Effect
- No Benefit
- Duration
- 3 months
- Population
- Patients with type 2 diabetes
- Participants
- 60
RCTGlycemic and oxidative status of patients with type 2 diabetes mellitus following oral administration of alpha-lipoic acid: a randomized double-blinded placebo-controlled study2012
6-month dose-ranging RCT in type 2 diabetes found ALA trended to lower fasting glucose and HbA1c dose-dependently and reduced urinary F2-isoprostanes versus placebo.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 1200 mg/day
- Population
- Diabetic patients
RCTEffect of alpha-lipoic acid on blood glucose, insulin resistance and glutathione peroxidase of type 2 diabetic patients2011n=57
8-week RCT in 57 type 2 diabetics given 300 mg/day ALA significantly lowered fasting and postprandial glucose and insulin resistance versus placebo.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 300 mg/day
- Population
- Diabetic patients
- Participants
- 57
RCTThe effects of lipoic acid and α-tocopherol supplementation on the lipid profile and insulin sensitivity of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial2011n=26
4-month RCT in 102 type 2 diabetics found LA and vitamin E, alone or combined, did not significantly change lipids or insulin sensitivity despite improved vitamin E/cholesterol ratio.
- Effect
- No Benefit
- Duration
- 4 months
- Dose
- 600 mg/day
- Population
- Diabetic patients
- Participants
- 26
Clinical trialThe Effect of Alpha-Lipoic Acid on Blood Pressure in Type 2 Diabetics2009
Clinical trial examined ALA effects on blood pressure in type 2 diabetes. Without abstract data, blood pressure benefit cannot be confirmed from available metadata alone.
- Effect
- No Benefit
- Population
- Diabetic patients
alpha-Lipoic acid treatment decreases serum lactate and pyruvate concentrations and improves glucose effectiveness in lean and obese patients with type 2 diabetes1999n=10
4-week study in 20 type 2 diabetics given 1200 mg/day LA increased glucose effectiveness and lowered lactate and pyruvate after glucose loading in lean and obese patients.
- Effect
- Benefit
- Duration
- 4 weeks
- Dose
- 1200 mg/day
- Population
- Diabetic patients
- Participants
- 10
RCTOral administration of RAC-alpha-lipoic acid modulates insulin sensitivity in patients with type-2 diabetes mellitus: a placebo-controlled pilot trial1999n=19
4-week multicenter RCT in 74 type 2 diabetics found oral ALA increased insulin-stimulated glucose disposal by 27% versus placebo across doses.
- Effect
- Benefit
- Dose
- 600 mg/day
- Population
- Diabetic patients
- Participants
- 19
Improvement of insulin-stimulated glucose-disposal in type 2 diabetes after repeated parenteral administration of thioctic acid1996n=20
10-day IV thioctic acid in 20 type 2 diabetics increased insulin-stimulated glucose disposal by about 30% versus baseline in an uncontrolled pilot trial.
- Effect
- Benefit
- Dose
- 0.4 mg/kg
- Population
- Patients with type 2 diabetes
- Participants
- 20
Controlled trialEnhancement of glucose disposal in patients with type 2 diabetes by alpha-lipoic acid1995n=7
Acute IV ALA at 1000 mg in 7 type 2 diabetic patients raised insulin-stimulated glucose clearance about 50% versus no change on vehicle in a small controlled study.
- Effect
- Benefit
- Dose
- 600 mg/day
- Population
- Diabetic patients
- Participants
- 7
RCT[Comparative study of alpha-lipoic acid and mexidol effects on affective status, cognitive functions and quality of life in diabetes mellitus patients]
2-week RCT in diabetic patients found IV ALA at 600 mg/day and mexidol each lowered hyperglycemia and improved mood-related measures versus baseline.
- Effect
- Benefit
- Dose
- 600 mg/day
- Population
- Diabetic patients
AstragalusView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Astragalus (40-60 grams dissolved into a hot drink) may help lower blood sugar and improve insulin resistance in people with type 2 diabetes.
- It may also slightly improve blood sugar control when added to metformin treatment.
Browse 3 studies·3 meta-analyses
MetaLong-term efficacy and safety of Huangqi-based Traditional Chinese Medicine in diabetic peripheral neuropathy: a meta-analysis of randomized controlled trials2024n=3,759
A meta-analysis of 48 RCTs in 3,759 diabetic peripheral neuropathy patients found astragalus-based TCM plus Western medicine reduced symptoms, IL-6, TNF-α, and glycemia versus Western medicine alone.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 3,759
MetaThe Efficacy and Safety of Astragalus as an Adjuvant Treatment for Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis2023n=953
A meta-analysis of 20 RCTs in 953 type 2 diabetes patients found astragalus plus metformin lowered fasting glucose, postprandial glucose, HbA1c, and HOMA-IR compared with metformin alone.
- Effect
- Benefit
- Dose
- 50 g/day
- Population
- Diabetic patients
- Participants
- 953
MetaThe effect of Astragalus as an adjuvant treatment in type 2 diabetes mellitus: A (preliminary) meta-analysis2016n=1,054
A meta-analysis including 13 studies with a total of 1054 participants found that both oral and IV astragalus administration significantly reduced fasting plasma glucose, postprandial plasma glucose (after a meal) but only oral astragalus significantly reduced fasting insulin and levels of HbA1c. Oral astragalus may be superior to IV astragalus as an adjuvant therapy in the treatment of type 2 diabetes.
- Effect
- Benefit
- Participants
- 1,054
BiotinView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Taking biotin by itself does not seem to lower blood sugar or improve insulin levels in people with or without diabetes.
- However, supplements combining biotin with chromium picolinate have shown benefits in people with poorly controlled type 2 diabetes, helping to lower blood sugar levels, HbA1c (a measure of long-term blood sugar control), and improve cholesterol and lipid levels.
- It is not clear whether the benefits come from biotin alone, chromium alone, or both together.
- These combination supplements appear to be safe and may help improve diabetes control when used along with regular diabetes medications.
Browse 5 studies·1 meta-analysis
Systematic reviewInfluence of biotin intervention on glycemic control and lipid profile in patients with type 2 diabetes mellitus: A systematic review and meta-analysis2022n=445
A meta-analysis of 5 RCTs (445 type 2 diabetic patients) found biotin for 28–90 days significantly lowered fasting glucose, total cholesterol, and triglycerides but not insulin; evidence for HbA1c and LDL was insufficient.
- Effect
- Benefit
- Duration
- 28–90 days
- Population
- Diabetic patients
- Participants
- 445
RCTChromium picolinate and biotin combination improves glucose metabolism in treated, uncontrolled overweight to obese patients with type 2 diabetes2008n=47
In 447 poorly controlled type 2 diabetic adults, 90 days of chromium picolinate (600 µg) plus biotin (2 mg) lowered HbA1c by 0.54% versus placebo, with greater fasting glucose reductions in those with baseline HbA1c ≥10%.
- Effect
- Benefit
- Duration
- 90 days
- Dose
- 2 mg
- Population
- Diabetic patients
- Participants
- 47
RCTBiotin supplementation reduces plasma triacylglycerol and VLDL in type 2 diabetic patients and in nondiabetic subjects with hypertriglyceridemia2006n=33
In 33 adults (diabetic and nondiabetic), 28 days of biotin (~61 µmol/day) significantly lowered plasma triglycerides and VLDL versus baseline but did not significantly change glucose, insulin, or cholesterol.
- Effect
- Benefit
- Duration
- 28 days
- Population
- Diabetic patients
- Participants
- 33
- Ages
- 30–65
RCTThe effect of chromium picolinate and biotin supplementation on glycemic control in poorly controlled patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial2006
In 43 type 2 diabetic patients, 4 weeks of chromium picolinate plus biotin (2 mg/day) reduced 2-h oral glucose tolerance area under the curve and fructosamine versus placebo, without serious adverse events.
- Effect
- Benefit
- Duration
- 4 weeks
- Dose
- 2 mg/day
- Population
- Diabetic patients
Clinical trialEffects of biotin on pyruvate carboxylase, acetyl-CoA carboxylase, propionyl-CoA carboxylase, and markers for glucose and lipid homeostasis in type 2 diabetic patients and nondiabetic subjects2004n=30
In 37 adults, 14–28 days of biotin raised lymphocyte pyruvate carboxylase, propionyl-CoA carboxylase, and acetyl-CoA carboxylase activity but did not change glucose, insulin, lactate, or lipids in diabetic or nondiabetic groups.
- Effect
- No Benefit
- Population
- Diabetic patients
- Participants
- 30
CocoaView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Some small studies suggest that taking cocoa by mouth may slightly improve blood sugar control in people with diabetes, but these changes are small and probably not important for health.
- Research combining results from several small studies shows cocoa can lower fasting blood sugar and "bad" cholesterol (LDL) a little, but does not improve long-term blood sugar control or other heart risk factors.
- Studies in the general population have found that eating up to 60 grams of chocolate per week might lower the risk of developing diabetes.
- However, a large, long-term study in older adults found that taking a cocoa extract daily did not reduce the chance of getting type 2 diabetes.
Browse 7 studies·3 meta-analyses
RCTCocoa Extract Supplementation and Risk of Type 2 Diabetes: The Cocoa Supplement and Multivitamin Outcomes Study (COSMOS) Randomized Clinical Trial2023n=12,666
In 18,381 older adults over 3.5 years, 500 mg/day cocoa flavanol extract did not reduce incident type 2 diabetes versus placebo.
- Effect
- No Benefit
- Dose
- 500 mg/day
- Population
- Older adults
- Participants
- 12,666
- Ages
- 65+
MetaEffects of cocoa products intake on cardiometabolic biomarkers of type 2 diabetes patients: a systematic review and meta-analysis based on both long-term and short-term randomised controlled trials2022
A meta-analysis of 12 trials found long-term cocoa product intake in type 2 diabetes lowered LDL, triglycerides, fasting glucose, and C-reactive protein.
- Effect
- Benefit
MetaThe effect of cocoa/dark chocolate consumption on lipid profile, glycemia, and blood pressure in diabetic patients: A meta-analysis of observational studies2021n=433
A meta-analysis of 8 RCTs (433 diabetic patients) found cocoa or dark chocolate reduced LDL cholesterol by 15.5 mg/dL and fasting glucose by 6.9 mg/dL.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 433
RCTRegular Intake of a Usual Serving Size of Flavanol-Rich Cocoa Powder Does Not Affect Cardiometabolic Parameters in Stably Treated Patients with Type 2 Diabetes and Hypertension-A Double-Blinded, Randomized, Placebo-Controlled Trial2018
In 42 stably treated type 2 diabetes patients with hypertension over 12 weeks, 2.5 g/day flavanol-rich cocoa did not change blood pressure, glucose, or lipids versus placebo.
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 2.5 g/day
- Population
- Diabetic patients
MetaChocolate Consumption and Risk of Coronary Heart Disease, Stroke, and Diabetes: A Meta-Analysis of Prospective Studies2017n=7
A meta-analysis of 14 prospective studies found higher chocolate intake associated with 10–18% lower risks of coronary heart disease, stroke, and diabetes, with optimal intake around 2–6 servings per week.
- Effect
- Benefit
- Participants
- 7
- Ages
- 5–16
RCTAcute Cocoa Supplementation Increases Postprandial HDL Cholesterol and Insulin in Obese Adults with Type 2 Diabetes after Consumption of a High-Fat Breakfast2015n=18
In 18 obese type 2 diabetes patients, acute high-polyphenol cocoa raised postprandial HDL and insulin after a high-fat meal but did not improve overall metabolic responses.
- Effect
- No Benefit
- Dose
- 960 mg/day
- Population
- Adults
- Participants
- 18
- Avg age
- ~56
RCTSustained benefits in vascular function through flavanol-containing cocoa in medicated diabetic patients a double-masked, randomized, controlled trial2008
In medicated type 2 diabetes patients over 30 days, flavanol-rich cocoa 321 mg three times daily increased flow-mediated dilation by 30% and sustained acute vascular benefits.
- Effect
- Benefit
- Duration
- 30 days
- Dose
- 963 mg/day
- Population
- Diabetic patients
Flaxseed OilView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Most studies show that flaxseed oil does not help control blood sugar or insulin levels in people with type 2 diabetes.
- However, in pregnant women with gestational diabetes, taking flaxseed oil daily for about six weeks might help lower blood sugar and improve how the body uses insulin.
- Some research combined flaxseed oil with vitamin E, but it’s not clear if the benefits come from flaxseed oil, vitamin E, or both.
- More research is needed to confirm these effects.
Browse 8 studies·2 meta-analyses
MetaFlaxseed supplementation significantly reduces hemoglobin A1c in patients with type 2 diabetes mellitus: A systematic review and meta-analysis2023
A meta-analysis of 13 T2DM trials found flaxseed supplementation significantly lowered HbA1c versus control, without consistent effects on weight, blood pressure, fasting glucose, or lipids overall.
- Effect
- Benefit
- Population
- Adults
RCTThe effects of n-3 fatty acids from flaxseed oil on genetic and metabolic profiles in patients with gestational diabetes mellitus: a randomised, double-blind, placebo-controlled trial2020n=60
In 60 women with gestational diabetes over 6 weeks, 2,000 mg/day flaxseed oil n-3s lowered fasting glucose, insulin, HOMA-IR, and triglycerides and modulated PPAR-gamma and inflammatory gene expression versus placebo.
- Effect
- Benefit
- Duration
- 6 weeks
- Dose
- 2000 mg/day
- Population
- Women
- Participants
- 60
RCTA comparison between the effects of flaxseed oil and fish oil supplementation on cardiovascular health in type 2 diabetic patients with coronary heart disease: A randomized, double-blinded, placebo-controlled trial2019n=30
In 90 T2DM patients with CHD over 12 weeks, 2,000 mg/day fish oil or flaxseed oil both reduced insulin and raised total antioxidant capacity versus placebo, with flaxseed also lowering hs-CRP.
- Effect
- Benefit
- Duration
- 12 weeks
- Population
- Diabetic patients
- Participants
- 30
MetaFlaxseed supplementation on glucose control and insulin sensitivity: a systematic review and meta-analysis of 25 randomized, placebo-controlled trials2018
A meta-analysis of 25 flaxseed RCTs found supplementation significantly reduced fasting glucose (−2.94 mg/dL), insulin, and HOMA-IR and increased insulin sensitivity, without significant HbA1c change.
- Effect
- Benefit
RCTClinical and metabolic response to flaxseed oil omega-3 fatty acids supplementation in patients with diabetic foot ulcer: A randomized, double-blind, placebo-controlled trial2017n=60
In 60 grade-3 diabetic foot ulcer patients over 12 weeks, flaxseed oil omega-3s 2,000 mg/day reduced ulcer dimensions and improved insulin, HOMA-IR, and HbA1c versus placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 2000 mg/day
- Participants
- 60
- Ages
- 40–85
RCTA randomized-controlled clinical trial investigating the effect of omega-3 fatty acids and vitamin E co-supplementation on markers of insulin metabolism and lipid profiles in gestational diabetes2015n=30
In 60 gestational diabetes patients over 6 weeks, 1,000 mg omega-3 from flaxseed oil plus 400 IU vitamin E lowered fasting glucose, insulin, and HOMA-IR significantly versus placebo.
- Effect
- Benefit
- Duration
- 6 weeks
- Dose
- 1000 mg omega-3 + 400 IU vitamin E/day
- Population
- Women
- Participants
- 30
RCTDietary milled flaxseed and flaxseed oil improve N-3 fatty acid status and do not affect glycemic control in individuals with well-controlled type 2 diabetes2010n=17
In 34 type 2 diabetes patients over 12 weeks, milled flaxseed 32 g/day or flaxseed oil 13 g/day (~7.4 g ALA) raised plasma n-3 status without changing HbA1c, glucose, insulin, or adipokines versus control bakery products.
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 7.4 g/day
- Population
- Adults
- Participants
- 17
- Avg age
- ~52
RCTHigh dose flaxseed oil supplementation may affect fasting blood serum glucose management in human type 2 diabetics2008n=12
In adults with type 2 diabetes, ~10 g/day flaxseed oil (~5.5 g ALA) for 3 months did not change fasting glucose, insulin, or HbA1c versus safflower oil placebo.
- Effect
- No Benefit
- Duration
- 3 months
- Dose
- 10 g/day
- Population
- Adults
- Participants
- 12
GingerView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Studies suggest that ginger supplements may help with blood sugar control in people with type 2 diabetes or gestational diabetes.
- In type 2 diabetes, daily ginger (1200–3000 mg for 8–13 weeks) has lowered long-term blood sugar (HbA1c) and fasting glucose in some studies, but other research found no benefit.
- In people with diabetes on dialysis, 2000 mg per day lowered fasting sugar and insulin resistance.
- In pregnant women with gestational diabetes, 1500 mg daily for 6 weeks slightly reduced fasting sugar and insulin, but did not affect blood sugar after meals.
Browse 5 studies·4 meta-analyses
MetaEffect of the Consumption of Species from the Zingiberaceae or Berberidaceae Family on Glycemic Profile Parameters: A Systematic Review and Meta-Analysis2025
A meta-analysis of Zingiberaceae and Berberidaceae plant extracts found significant reductions in fasting glucose, HbA1c, fasting insulin, and HOMA-IR, with stronger effects for berberidaceae species.
- Effect
- Benefit
MetaThe effect of oral supplementation of ginger on glycemic control of patients with type 2 diabetes mellitus - A systematic review and meta-analysis2024
A meta-analysis found ginger supplementation significantly reduced fasting blood glucose and HbA1c in type 2 diabetes patients versus placebo across 4–12 week trials.
- Effect
- No Benefit
- Duration
- 4–12 weeks
- Dose
- 2 g/day
- Population
- Diabetic patients
RCTThe effect of zingiber officinale on prooxidant-antioxidant balance and glycemic control in diabetic patients with ESRD undergoing hemodialysis: a double-blind randomized control trial2023
In 44 diabetic hemodialysis patients, ginger 2000 mg/day for 8 weeks improved prooxidant-antioxidant balance and glycemic control versus placebo.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 2000 mg/day
- Population
- Diabetic patients
MetaThe effect of ginger supplementation on metabolic profiles in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials2022
A meta-analysis found ginger supplementation significantly reduced fasting glucose, HbA1c, total cholesterol, LDL, and triglycerides in type 2 diabetes versus control.
- Effect
- Benefit
- Population
- Diabetic patients
RCTEffects of Ginger (Zingiber officinale Roscoe) on Type 2 Diabetes Mellitus and Components of the Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2018n=490
A meta-analysis of 490 type 2 diabetes patients found ginger significantly reduced fasting glucose, HbA1c, and LDL cholesterol versus placebo.
- Effect
- Benefit
- Population
- Adults
- Participants
- 490
KefirView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- A summary of six small studies in healthy people and in those with diabetes, metabolic syndrome, or overweight found that drinking kefir (180–1200 mL daily for 2–12 weeks) lowered fasting blood sugar by about 10 points, but did not improve long-term blood sugar control (HbA1c).
- The findings are less certain because the studies varied widely in dose, length, and participants.
Browse 3 studies·1 meta-analysis
MetaEffect of kefir beverage consumption on glycemic control: A systematic review and meta-analysis of randomized controlled clinical trials2021n=323
A meta-analysis of kefir trials found kefir consumption significantly reduced fasting glucose and HbA1c in patients with type 2 diabetes versus control.
- Effect
- Benefit
- Participants
- 323
Effect of Probiotic Fermented Milk (Kefir) on Some Blood Biochemical Parameters Among Newly Diagnosed Type 2 Diabetic Adult Males in Gaza Governorate2019
In newly diagnosed adult males with type 2 diabetes, probiotic fermented kefir milk improved several blood biochemical parameters versus control over the intervention period.
- Effect
- Benefit
- Population
- Adults
RCTEffect of probiotic fermented milk (kefir) on glycemic control and lipid profile in type 2 diabetic patients: a randomized double-blind placebo-controlled clinical trial2015n=30
In 30 type 2 diabetes patients, probiotic kefir 600 mL/day for 8 weeks lowered fasting glucose, insulin, HOMA-IR, and LDL cholesterol versus fermented milk control.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 600 mL/day
- Population
- Diabetic patients
- Participants
- 30
- Ages
- 35–65
LuteinView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Some research links low blood levels of lutein and other carotenoids with higher risk of poor blood sugar control, possibly suggesting a role in preventing diabetes.
- However, eating more lutein-rich foods does not seem to lower the risk of developing type 2 diabetes.
- Also, people with type 2 diabetes who have higher lutein levels in their blood do not appear to have a lower risk of heart problems.
- Early studies suggest lutein and zeaxanthin might help protect the eyes in diabetes, but more research is needed.
Browse 4 studies·1 meta-analysis
ObservationalAssociations of Serum Carotenoids With Risk of Cardiovascular Mortality Among Individuals With Type 2 Diabetes: Results From NHANES2022n=3,107
In 3,107 adults with type 2 diabetes, higher serum beta-carotene was associated with increased cardiovascular mortality (HR 2.47 top vs bottom quartile); lutein/zeaxanthin showed no significant association.
- Effect
- No Benefit
- Duration
- 14 years
- Population
- Adults
- Participants
- 3,107
MetaThe effects of lutein on cardiometabolic health across the life course: a systematic review and meta-analysis2016n=387,569
A systematic review and meta-analysis found lutein intake inversely associated with some cardiometabolic outcomes but evidence varied by life stage and endpoint.
- Effect
- Benefit
- Population
- Pregnant women
- Participants
- 387,569
ObservationalDiabetes mellitus and serum carotenoids: findings of a population-based study in Queensland, Australia2005n=1,597
In 1,597 Australian adults, serum lutein/zeaxanthin and other carotenoids except lycopene were inversely associated with type 2 diabetes and impaired glucose metabolism.
- Effect
- Benefit
- Population
- Adults
- Participants
- 1,597
- Ages
- ≥25
ObservationalDietary antioxidant intake and risk of type 2 diabetes2004n=2,285
In 4,304 Finnish adults followed 23 years, higher beta-cryptoxanthin intake was associated with reduced type 2 diabetes risk (RR 0.58); vitamin E showed the strongest antioxidant association.
- Effect
- No Benefit
- Population
- Patients with type 2 diabetes
- Participants
- 2,285
- Ages
- 40–69
LycopeneView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Research shows that eating more lycopene does not lower the chance of developing type 2 diabetes, and higher blood levels of lycopene in people with diabetes do not reduce heart-related deaths.
- Some small studies suggest that taking lycopene or tomato extract supplements may slightly lower blood sugar in people with diabetes.
- More studies are needed to know if lycopene can help in the management of diabetes.
Browse 3 studies·1 meta-analysis
ObservationalAssociations of Serum Carotenoids With Risk of Cardiovascular Mortality Among Individuals With Type 2 Diabetes: Results From NHANES2022n=3,107
In 3,107 adults with type 2 diabetes, higher serum beta-carotene was associated with increased cardiovascular mortality (HR 2.47 top vs bottom quartile); lutein/zeaxanthin showed no significant association.
- Effect
- No Benefit
- Duration
- 14 years
- Population
- Adults
- Participants
- 3,107
MetaEffect of Lycopene Intake on the Fasting Blood Glucose Level: A Systematic Review with Meta-Analysis2022n=750
A meta-analysis of 11 trial arms (n=750) found lycopene intake trended toward lower fasting blood glucose (SMD −0.15, p=0.05), with a significant reduction in type 2 diabetes patients (SMD −0.37, n=152).
- Effect
- Benefit
- Population
- Adults
- Participants
- 750
- Ages
- 18+
RCTThe consumption of lycopene and tomato-based food products is not associated with the risk of type 2 diabetes in women2006n=35,783
A prospective cohort of 35,783 women followed ~10 years found no association between dietary lycopene or tomato product intake and type 2 diabetes risk across quintiles.
- Effect
- No Benefit
- Population
- Women
- Participants
- 35,783
- Ages
- ≥45
MelatoninView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Most studies suggest melatonin can help improve blood sugar control in people with various health conditions.
- Taking 3 to 10 mg for 2 to 6 months may reduce blood sugar and a measure called HbA1c.
- However in people with type 2 diabetes, evidence is limited and mixed.
- Some small studies did not find clear benefits from melatonin for blood sugar control in type 2 diabetes.
Browse 6 studies·3 meta-analyses
RCTGlycemic Variability in Patients with Type 2 Diabetes Mellitus (T2DM): The Role of Melatonin in a Crossover, Double-Blind, Placebo-Controlled, Randomized Study2023n=30
A crossover RCT of 30 type 2 diabetes patients found 3 mg/night melatonin for 7 days increased post-breakfast glycemic variability vs placebo.
- Effect
- No Benefit
- Duration
- 7 days
- Dose
- 3 mg
- Population
- Diabetic patients
- Participants
- 30
RCTConsumption of melatonin supplement improves cardiovascular disease risk factors and anthropometric indices in type 2 diabetes mellitus patients: a double-blind, randomized, placebo-controlled trial2021n=25
An 8-week RCT of 50 type 2 diabetes patients found melatonin (500 mg tablets, ~250 mg elemental) significantly reduced systolic BP, MAP, weight, BMI, and waist circumference vs placebo.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 250 mg
- Population
- Diabetic patients
- Participants
- 25
- Ages
- 30–60
MetaEffects of melatonin supplementation on diabetes: A systematic review and meta-analysis of randomized clinical trials2021
A meta-analysis of diabetes RCTs found melatonin supplementation did not significantly improve insulin resistance or glycated hemoglobin compared with placebo.
- Effect
- No Benefit
- Population
- Diabetic patients
MetaEffects of Melatonin Supplementation on Insulin Levels and Insulin Resistance: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2021n=376
A meta-analysis of 8 RCTs (376 participants) found melatonin supplementation reduced insulin levels and HOMA-IR and increased QUICKI vs control.
- Effect
- Benefit
- Participants
- 376
RCTEffect of Bedtime Melatonin Administration in Patients with Type 2 Diabetes: A Triple-Blind, Placebo-Controlled, Randomized Trial2019n=36
An 8-week RCT of 70 type 2 diabetes patients found 6 mg/night melatonin did not improve fasting glucose, HbA1c, or insulin resistance indices vs placebo.
- Effect
- No Benefit
- Duration
- 8 weeks
- Dose
- 6 mg/day
- Population
- Diabetic patients
- Participants
- 36
- Avg age
- ~58
MetaThe Effects of Melatonin Supplementation on Glycemic Control: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2018
A meta-analysis of 12 RCTs found melatonin supplementation significantly reduced fasting glucose and increased QUICKI, but did not significantly change HOMA-IR or HbA1c.
- Effect
- Benefit
Vitamin B9 (Folate)View supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Small clinical studies show that taking folic acid supplements does not clearly improve long-term blood sugar control (measured by HbA1c) in people with type 2 diabetes.
- Some research suggests that folic acid may slightly lower fasting blood sugar and insulin levels, but these changes are small and it is unclear if they help prevent diabetes complications.
- People with type 2 diabetes who eat more folate-rich foods may have a lower risk of heart disease.
Browse 5 studies·3 meta-analyses
ObservationalDietary Folate, Vitamin B6, and Vitamin B12 and Risk of Cardiovascular Diseases among Individuals with Type 2 Diabetes: A Case-Control Study2023n=419
A case-control study of 419 Chinese adults with type 2 diabetes found highest-quartile folate intake associated with lower CVD risk (OR 0.32) versus lowest quartile.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 419
MetaThe Influence of Maternal Folate Status on Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis2023
A systematic review found higher serum and red blood cell folate in pregnancy associated with increased gestational diabetes risk, especially in the second trimester.
- Population
- Women
MetaFolic Acid Supplementation Improves Glycemic Control for Diabetes Prevention and Management: A Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials2021
A meta-analysis of 24 RCTs found folic acid modestly lowered fasting glucose, fasting insulin, and HOMA-IR in adults; HbA1c was unchanged.
- Effect
- Benefit
- Population
- Adults
RCTFolic acid and vitamin B12 supplementation in subjects with type 2 diabetes mellitus: A multi-arm randomized controlled clinical trial2020n=80
An RCT in 80 type 2 diabetes patients found add-on methylcobalamin (with or without folic acid) improved HbA1c and insulin resistance over 8 weeks versus standard therapy.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 5 mg/day
- Population
- Diabetic patients
- Participants
- 80
MetaEffect of folic acid supplementation on plasma total homocysteine levels and glycemic control in patients with type 2 diabetes: a systematic review and meta-analysis2012n=183
A meta-analysis of 4 RCTs in 183 type 2 diabetes patients found folic acid lowered homocysteine but did not significantly reduce HbA1c versus placebo.
- Effect
- No Benefit
- Population
- Diabetic patients
- Participants
- 183
Vitamin KView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is not clear if taking vitamin K by mouth helps control blood sugar in people with diabetes.
- One small study found that taking vitamin K2 (180 micrograms twice daily) for 12 weeks lowered long-term blood sugar (HbA1c) by 1.6%, while people on placebo had a slight increase.
- However, many people dropped out of the placebo group, which may affect results.
- Another review of studies showed vitamin K1 or K2 might slightly improve fasting blood sugar and insulin resistance, but the studies used different forms and doses.
- A small study with vitamin K4 found no change in blood sugar but some improvement in insulin resistance and ability to reduce diabetes medications.
Browse 7 studies·4 meta-analyses
MetaEffect of Menaquinone-7 (MK-7) Supplementation on Anthropometric Measurements, Glycemic Indices, and Lipid Profiles: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2025
In a meta-analysis in adults, based on the findings of the present systematic review and meta-analysis, MK-7 may have beneficial effects on glycemic control and TC, although further highly qualified original research is needed for a consistent conclusion.
- Effect
- Benefit
- Population
- Adults
RCTThe effect of vitamin K4 supplementation on insulin resistance in individuals with type 2 diabetes: a double-blind randomised placebo-controlled clinical trial2023n=106
In an RCT of 106 participants, 1 mg vitamin K4/day, for 24 weeks, however, it did not affect fasting plasma glucose (FPG) or glycated haemoglobin (HbA 1 c).
- Effect
- No Benefit
- Duration
- 24 weeks
- Dose
- 1 mg vitamin K4/day
- Population
- Pregnant women
- Participants
- 106
- Ages
- 18–65
MetaThe relationship between vitamin K and T2DM: a systematic review and meta-analysis2023n=813
In a meta-analysis of 813 participants, results : A meta -analysis of seven studies (813 participants) found vitamin K supplementation significantly reduced FBS (SMD = -0.150 mg dl -1 , 95% CI = -0.290, -0.010 mg dl -1 ) and HOMA-IR (SMD = -0.200, 95% CI = -0.330, -0.060), but not FINS.
- Effect
- Benefit
- Participants
- 813
RCTGlycemic control improvement in individuals with type 2 diabetes with vitamin K2 supplementation: a randomized controlled trial2021
In an RCT in diabetic patients, 360 mcg/day, for 12 weeks, no significant variation was observed in lipid profiles.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 360 mcg/day
- Population
- Diabetic patients
MetaEffect of Vitamin K Supplementation on Glycemic Control: A Systematic Review and Meta-Analysis of Clinical Trials2018n=533
In a meta-analysis of 533 participants, in conclusion, vitamin K supplementation had no significant effect on glycemic control in healthy subjects.
- Effect
- Benefit
- Dose
- 0.91 mg/day
- Population
- Healthy adults
- Participants
- 533
RCTEffect of vitamin K supplementation on insulin sensitivity: a meta-analysis2017n=1,077
In an RCT of 1,077 participants, vitamin K supplementation did not affect insulin sensitivity as measured by homeostasis model assessment of insulin resistance, fasting plasma glucose, fasting plasma insulin, C-reactive protein, adiponectin, leptin, and interleukin-6 levels.
- Effect
- No Benefit
- Population
- Postmenopausal women
- Participants
- 1,077
ObservationalBias or biology: evaluating the epidemiologic studies of L-tryptophan and the eosinophilia-myalgia syndrome1996
In an observational study, the search for the cause of EMS should continue without the underlying assumption that LT or some contaminant is responsible.
American GinsengView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is unclear if American ginseng helps diabetes.
- Some small studies found that taking 3 grams before meals lowered blood sugar levels after eating in people with type 2 diabetes.
- Taking more than 3 grams didn't help more.
- A combination of American and Panax ginseng taken daily for 12 weeks lowered blood sugar control and top blood pressure numbers slightly.
- However, the most effective form of ginseng is unknown.
Browse 4 studies
RCTEffect of coadministration of enriched Korean Red Ginseng (Panax ginseng) and American ginseng (Panax quinquefolius L) on cardiometabolic outcomes in type-2 diabetes: A randomized controlled trial2021n=80
In 80 type 2 diabetes patients with hypertension, 12 weeks of combined Rg3-enriched Korean red ginseng plus American ginseng 2.25 g/day lowered 24-hour systolic BP 4 mmHg and HbA1c 0.35% versus control.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 2.25 g/day
- Population
- Diabetic patients
- Participants
- 80
RCTVariable effects of American ginseng: a batch of American ginseng (Panax quinquefolius L.) with a depressed ginsenoside profile does not affect postprandial glycemia2003n=12
In 12 healthy adults, a low-ginsenoside American ginseng batch (6 g before OGTT) did not reduce postprandial glucose or insulin, unlike prior batches with higher ginsenoside ratios.
- Effect
- No Benefit
- Dose
- 6 g/day
- Population
- Older adults
- Participants
- 12
- Avg age
- ~31
RCTAmerican ginseng (Panax quinquefolius L) reduces postprandial glycemia in nondiabetic subjects and subjects with type 2 diabetes mellitus2000
In 10 nondiabetic and 9 type 2 diabetic subjects, 3 g American ginseng before a glucose challenge reduced postprandial glycemia 18–22%; in nondiabetics benefit required taking ginseng 40 minutes before glucose.
- Effect
- Benefit
- Dose
- 3 g/day
- Population
- Diabetic patients
- Avg age
- 34±7
RCTSimilar postprandial glycemic reductions with escalation of dose and administration time of American ginseng in type 2 diabetes2000
In 10 type 2 diabetics, 3, 6, or 9 g American ginseng given 0–120 minutes before a glucose challenge similarly reduced postprandial area under the curve by 15–20%; no dose or timing advantage beyond 3 g.
- Effect
- Benefit
- Dose
- 3 g/day
- Population
- Diabetic patients
- Avg age
- ~63
BoswelliaView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is unclear if taking Boswellia serrata helps control blood sugar in type 2 diabetes.
- Some studies suggest that taking Boswellia for 6 to 12 weeks can lower long-term blood sugar (HbA1c) but may not change fasting blood sugar.
- It might also lower triglycerides but does not appear to affect other cholesterol levels.
- The studies varied in dose and length, and more research is needed.
Browse 2 studies·2 meta-analyses
Systematic reviewEffect of boswellia (Boswellia serrata L.) supplementation on glycemic markers and lipid profile in type 2 diabetic patients: a systematic review and meta-analysis2024n=287
A 2024 meta-analysis of 5 RCTs (287 type 2 diabetes patients) found boswellia significantly lowered HbA1c, total cholesterol, triglycerides, and LDL versus placebo; fasting glucose reduction was not significant.
- Effect
- Benefit
- Population
- Diabetic patients
- Participants
- 287
Systematic reviewEffectiveness and Safety of Ayurvedic Medicines in Type 2 Diabetes Mellitus Management: A Systematic Review and Meta-Analysis2022n=21,191
A systematic review of 199 Ayurvedic medicine RCTs (21,191 participants) found Boswellia serrata reduced HbA1c by 0.5% (95% CI −0.7 to −0.4) compared with control in type 2 diabetes.
- Effect
- Benefit
- Population
- Adults
- Participants
- 21,191
GinkgoView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Research is mixed on ginkgo for type 2 diabetes.
- One study found people on metformin lowered their average blood sugar and insulin after 3 months of ginkgo extract (120 mg daily).
- But larger reviews show no overall blood sugar benefits, with some even suggesting a small increase.
- The only clear benefits seen were a small rise in “good” cholesterol and better blood flow in the legs, which may help circulation problems related to diabetes.
Browse 2 studies·1 meta-analysis
MetaEffects and safety of Ginkgo biloba on blood metabolism in type 2 diabetes mellitus: a systematic review and meta-analysis2023n=1,573
A meta-analysis found Ginkgo biloba supplementation modestly improved fasting glucose and lipids in type 2 diabetes without increasing adverse events versus control.
- Effect
- No Benefit
- Population
- Diabetic patients
- Participants
- 1,573
RCTEffect of Ginkgo leaf extract on vascular endothelial function in patients with early stage diabetic nephropathy2009
In an 8-week RCT of 64 early diabetic nephropathy patients, ginkgo leaf extract added to conventional diabetes care improved vascular endothelial function versus control.
- Effect
- Benefit
- Duration
- 8 weeks
- Population
- Diabetic nephropathy patients
PotassiumView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It’s not clear if eating more potassium helps lower the risk of developing diabetes.
- One analysis of seven large studies found that people who got about 3300–3500 mg of potassium a day had about a 20% lower risk of diabetes compared to those getting less than 1000 mg a day.
- Results were similar whether potassium intake was estimated from diet surveys or urine tests.
- However, more research is needed.
Browse 1 study·1 meta-analysis
MetaDietary Potassium Intake and Risk of Diabetes: A Systematic Review and Meta-Analysis of Prospective Studies2022
A meta-analysis of 7 prospective studies found inverse nonlinear association between dietary potassium ≥2900 mg/day and diabetes risk.
- Effect
- Benefit
- Dose
- 2900 mg/day
QuercetinView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Early research in people with type 2 diabetes who are not taking diabetes medicines shows that taking a supplement with quercetin, myricetin, and chlorogenic acid (called Emulin) for one week can lower fasting and after-meal blood sugar levels by about 5%.
- In people who take the diabetes medicine metformin, adding this supplement lowered fasting blood sugar by about 20%, much more than metformin alone.
- More studies are needed to confirm these benefits.
Browse 3 studies
Open-labelBenefits of Quercetin on Glycated Hemoglobin, Blood Pressure, PiKo-6 Readings, Night-Time Sleep, Anxiety, and Quality of Life in Patients with Type 2 Diabetes Mellitus: A Randomized Controlled Trial2024n=50
In 88 type 2 diabetes patients, quercetin 500 mg/day for 12 weeks lowered HbA1c −4.0% versus +0.1% in control and improved anxiety and quality-of-life scores.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 500 mg/day
- Population
- Diabetic patients
- Participants
- 50
RCTThe Impact of Three-Month Quercetin Intake on Quality of Life and Anxiety in Patients With Type II Diabetes Mellitus: An Early Data Analysis From a Randomized Controlled Trial2024n=50
In 38 type 2 diabetes patients at 12-week interim follow-up, quercetin 500 mg/day improved FEV1 (+6.8% vs −0.3% in control) alongside usual care versus standard treatment alone.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 500 mg/day
- Population
- Diabetic patients
- Participants
- 50
- Ages
- 50+
RCTEffect of emulin on blood glucose in type 2 diabetics2013
In 40 type 2 diabetics over 1 week, Emulin (quercetin-containing blend) with metformin lowered postprandial glucose and AUC more than either alone.
- Effect
- Benefit
- Duration
- 1 week
AstaxanthinView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Research on astaxanthin for diabetes shows mixed results.
- A small study found astaxanthin supplementation did not lower blood sugar or cholesterol much but slightly reduced belly fat and systolic blood pressure.
- Other studies suggest astaxanthin may improve blood sugar control and reduce diabetic complications, but more research is needed.
Browse 1 study
RCTAstaxanthin improves glucose metabolism and reduces blood pressure in patients with type 2 diabetes mellitus2018n=44
In 44 type 2 diabetes patients over 8 weeks, astaxanthin 8 mg/day raised adiponectin, reduced visceral fat and triglycerides, and lowered systolic BP, without lowering fasting glucose significantly.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 8 mg/day
- Population
- Adults
- Participants
- 44
BilberryView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is unclear if bilberry helps people with type 2 diabetes.
- One small study showed that taking a single dose of bilberry extract before a glucose test helped lower blood sugar.
- But another small study found that taking bilberry twice daily for 4 weeks did not improve blood sugar control or other health markers.
- Research suggests bilberry might work in several ways to help control blood sugar, but more studies are needed to know if it really benefits people with diabetes.
Browse 2 studies
RCTImpact of short-term bilberry supplementation on glycemic control, cardiovascular disease risk factors, and antioxidant status in Chinese patients with type 2 diabetes2021n=20
A 4-week, randomized, double-blind, placebo-controlled cross-over study in Chinese adults with type 2 diabetes (n≈20) found that supplementation with 1.4 g/day of bilberry extract reduced HbA₁c by ~0.31% (though not significantly vs placebo) and showed tendencies toward improved glycemic control, but no significant changes in body weight, blood pressure, lipids or antioxidant/inflammatory markers.
- Effect
- No Benefit
- Duration
- 4 weeks
- Dose
- 1.4 g/day
- Population
- Adults
- Participants
- 20
RCTA single supplement of a standardised bilberry (Vaccinium myrtillus L.) extract (36 % wet weight anthocyanins) modifies glycaemic response in individuals with type 2 diabetes controlled by diet and lifestyle2013n=8
A single-dose, double-blind, cross-over trial in male volunteers with type 2 diabetes controlled by diet and lifestyle (n=8) showed that ingestion of 0.47 g of a standardized bilberry extract significantly lowered the incremental area under the curve (AUC) for glucose (P=0.003) and insulin (P=0.03) after a 75 g polysaccharide drink, versus placebo.
- Effect
- Benefit
- Dose
- 50 g/day
- Population
- Men
- Participants
- 8
- Avg age
- ~62
Casein ProteinView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- In people with diabetes, drinking a carbohydrate drink that includes casein protein can raise insulin levels and may slightly lower blood sugar compared to a placebo drink.
- In another small study, taking 15 grams of sodium caseinate (a form of casein) did not reduce blood sugar after a meal, but it did raise insulin and glucagon levels.
Browse 2 studies
RCTProtein co-ingestion strongly increases postprandial insulin secretion in type 2 diabetes patients2014n=60
In 60 men with type 2 diabetes, adding intact or hydrolyzed protein to carbohydrate doubled postprandial insulin secretion in nearly all participants.
- Effect
- Benefit
- Dose
- 0.7 g/kg
- Population
- Pregnant women
- Participants
- 60
RCTHydrolyzed casein decreases postprandial glucose concentrations in T2DM patients irrespective of leucine content2011
In type 2 diabetes patients, a hydrolyzed casein preload lowered 4-hour postprandial glucose ~4.7% vs placebo; unhydrolyzed casein had a smaller effect.
- Effect
- Benefit
- Population
- Diabetic patients
EleutheroView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- In people with type 2 diabetes, taking a specific eleuthero extract daily for 3 months lowered fasting and after-meal blood sugar, HbA1c (long-term blood sugar), triglycerides, and cholesterol compared to placebo.
- Research indicates eleuthero may improve how the body uses insulin and protect insulin-producing cells, which could help control diabetes.
- Preclinical and animal studies suggest eleutheroside E improves insulin sensitivity, protects pancreatic beta cells, and regulates glucose metabolism, supporting the hypoglycemic effects observed.
Browse 1 study
RCTSiberian Ginseng Results in Beneficial Effects on Glucose Metabolism in Diabetes Type 2 Patients: A Double Blind Placebo-Controlled Study in Comparison to Panax Ginseng2013
A 2013 double-blind placebo-controlled study in type 2 diabetes compared Siberian ginseng with Panax ginseng for glucose metabolism; detailed outcome data were not available in the indexed abstract.
Fish OilView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Taking fish oil does not improve blood sugar control or protect against heart problems in people with type 2 diabetes, but it may help lower high triglyceride levels.
- Most studies find that fish oil lowers triglycerides, especially in people with very high levels, but it does not change blood sugar or HbA1c.
- A large study found no benefit of fish oil on heart attacks, strokes, or similar problems when taken long-term.
- Some research suggests people over 60 with diabetes who regularly take fish oil may have a lower risk of dementia.
- Fish oil does not prevent diabetes during pregnancy, and it does not lower blood sugar in pregnant women, but a few small studies show it might help improve insulin resistance during gestational diabetes.
Browse 18 studies·5 meta-analyses
RCTComparison of the efficacy of fish oil and probiotic supplementation on glucose and lipid metabolism in patients with type 2 diabetes: a systematic review and network meta-analysis2024
A meta-analysis of 60 RCTs involving 3845 type 2 diabetes patients compared the efficacy of fish oil or probiotic supplementation on lipid metabolism and blood glucose control. It found that fish oil was superior to probiotics for lowering triglyceride and total cholesterol levels. A specific probiotic, Bifidobacterium, demonstrated the highest efficacy in reducing HbA1c levels. Probiotics were more effective for reducing HOMA-IR whilst fish oil led to greater increases in adiponectin levels and larger reductions in leptin and TNF-α. [10662]
- Effect
- Benefit
- Population
- Diabetic patients
MetaEffect of fish-oil supplementation on the glycemic and lipidemic profiles of pregnant women: a systematic review and meta-analysis2024
A meta-analysis of 15 pregnancy trials found fish oil had no overall effect on glycemic or lipid profiles, though subgroup analysis showed modest improvements in insulin and HOMA-IR.
- Effect
- No Benefit
- Dose
- 2.11 IU/day
- Population
- Women
ObservationalFish oil supplementation and risk of dementia among diabetic patients: a prospective study of 16,061 older patients2024n=16,061
In 16,061 UK Biobank diabetic patients ≥60 followed ~7.7 years, habitual fish oil use was associated with 24% lower dementia risk (HR 0.76, 95% CI 0.60–0.98) versus non-users.
- Duration
- 60 years
- Population
- Diabetic patients
- Participants
- 16,061
- Ages
- 60+
RCTThe impact of fish oil and/or probiotics on serum fatty acids and the interaction with low-grade inflammation in pregnant women with overweight and obesity: secondary analysis of a randomised controlled trial2024n=439
In 439 pregnant women with overweight/obesity, fish oil 1.9 g DHA + 0.22 g EPA/day raised serum EPA and DHA in phospholipids and cholesteryl esters versus placebo, with or without probiotics.
- Dose
- 1.9 g DHA + 0.22 g EPA/day
- Population
- Women
- Participants
- 439
RCTEffect of coadministration of omega-3 fatty acids with glimepiride on glycemic control, lipid profile, irisin, and sirtuin-1 in type 2 diabetes mellitus patients: a randomized controlled trial2023n=35
In 70 type 2 diabetes patients on glimepiride over 12 weeks, added fish oil 1,000 mg/day improved lipid profile and metabolic markers including irisin and sirtuin-1 versus corn oil placebo.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 1000 mg/day
- Population
- Diabetic patients
- Participants
- 35
- Ages
- 30–60
RCTEffect of fish oil supplementation combined with high-intensity interval training in newly diagnosed non-obese type 2 diabetes: a randomized controlled trial2020
A 3-mth study assigned 173 newly diagnosed type 2 diabetes patients to a fish oil group (2 g/day), fish oil + HIIT group (Mon, Wed, Fri; 10 x 60-sec cycling bouts) or a control group. The high-intensity interval training + 2 g/day fish oil group experienced significant additive beneficial effects on haemoglobin A1c, fasting glucose, HOMA-IR, adiponectin, fat mass and total cholesterol, but not fasting insulin compared to fish oil without exercise. [10664]
- Duration
- 3 months
- Dose
- 2.0 g/day
- Population
- Newly diagnosed non-obese type 2 diabetes patients
MetaEffects of fish oil supplementation on glucose control and lipid levels among patients with type 2 diabetes mellitus: a Meta-analysis of randomized controlled trials2020
A meta-analysis of 12 RCTs (1 – 6 months, 6 high quality studies) found that fish oil supplementation did not have a significant effect on glucose control outcomes including fasting insulin, glycosylated hemoglobin and HOMA-IR levels compared to placebo. Levels of HDL-C were higher in the Asian subgroup. [10663]
- Effect
- Benefit
- Duration
- 1–6 months
- Population
- Diabetic patients
Systematic reviewOmega-3 fatty acid supplementation does not prevent serious vascular events in people with diabetes2019
The ASCEND trial reported that omega-3 fatty acid supplementation did not prevent serious vascular events in people with diabetes compared with olive oil placebo.
- Effect
- No Benefit
Effect of Omega-3 Fatty Acid on the Fatty Acid Content of the Erythrocyte Membrane and Proteinuria in Patients with Diabetic Nephropathy2015n=19
A 12-wk study of 19 diabetic nephropathy patients taking angiotensin converting enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARB) for at least 6 months found that omega-3 supplementation (Omacar, 3 g/day) did not reduce proteinuria compared to placebo. Omega-3 supplementation significantly increased erythrocyte membrane concentrations of omega-3 fatty acids, and decreased omega-6 : omega-3 fatty acid ratio. [10666]
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 3 g/day
- Population
- Diabetic nephropathy patients
- Participants
- 19
RCTFish-oil supplementation in pregnancy does not reduce the risk of gestational diabetes or preeclampsia2012n=2,399
In 2,399 pregnant women (<21 weeks) to birth, 800 mg/day DHA-enriched fish oil did not reduce gestational diabetes (RR 0.97) or preeclampsia (RR 0.87) versus vegetable oil placebo in the DOMInO trial.
- Effect
- No Benefit
- Duration
- 21 weeks
- Dose
- 800 mg/day
- Population
- Women
- Participants
- 2,399
RCTFish-oil supplement has neutral effects on vascular and metabolic function but improves renal function in patients with Type 2 diabetes mellitus2010n=49
A 12-week study of 97 type 2 diabetes patients without cardiovascular disease found 4 g/day fish oil did not improve vascular function as measured by flow-mediated dilation. Those taking fish oil had lower serum creatinine (-4.5 micromol/l) compared to placebo. There was a significant reduction in serum triglycerides from omega-3 supplementation (-0.46 mmol/l). [10667]
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 4 g/day
- Population
- Diabetic patients
- Participants
- 49
RCTEffects of omega-3 fatty acid supplements on serum lipids, apolipoproteins and malondialdehyde in type 2 diabetes patients2008
A 10-week study of 50 type 2 diabetes patients found that 2 g/day omega-3 fatty acids had no significant effect on serum lipid levels, glucose, insulin, ApoA-I and HbA1c. [10668]
- Effect
- No Benefit
- Duration
- 10 weeks
- Dose
- 2 g/day
- Population
- Type 2 diabetes patients
MetaOmega-3 polyunsaturated fatty acids (PUFA) for type 2 diabetes mellitus2008n=1,075
A meta-analysis of 23 randomised controlled trials with 1075 participants with mean duration of 8.9 weeks given a mean dose of 3.5 g/day omega-3 PUFA found no significant effect on glycemic control. [10669]
- Effect
- No Benefit
- Duration
- 8.9 weeks
- Dose
- 3.5 g/day
- Population
- Type 2 diabetes patients
- Participants
- 1,075
Systematic reviewFish oil supplementation in type 2 diabetes: a quantitative systematic review2000n=823
A meta-analysis of 18 studies (mean 12 weeks duration) including 823 subjects found that fish oil (3 to 18 g/day) demonstrated a significant dose-dependent effect for lowering triglycerides (-0.56 mmol/l [95% CI -0.71 to -0.41]) and raising LDL cholesterol (0.21 mmol/l [0.02 to 0.41]). The triglyceride-lowering effect was greater in hypertriglyceridemic subjects [10670]. This study is similar to a 2001 study [10671].
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 18 g/day
- Population
- Diabetic patients
- Participants
- 823
RCTLong-term effects of fish oil on lipoprotein subfractions and low density lipoprotein size in non-insulin-dependent diabetic patients with hypertriglyceridemia1999n=8
A previously mentioned 6-mth study of 16 NIDDM hypertriglyceridemic patients found that moderate fish oil supplementation did not affect LDL cholesterol size or distribution. [10672]
- Effect
- No Benefit
- Duration
- 6 months
- Population
- Diabetic patients
- Participants
- 8
RCTEffect of omega 3 fatty acid on plasma lipids, cholesterol and lipoprotein fatty acid content in NIDDM patients1997n=18
A cross-over study of 28 type 2 diabetes patients found that 35 mg/kg bw/day EPA + DHA (for 60 kg person this is 2.1 g/day) taken for 3 months did not affect insulin, glucagon, C-peptide, HDL-C or LDL-C levels compared to olive oil placebo. [10674]
- Effect
- No Benefit
- Duration
- 3 months
- Dose
- 2.1 g/day
- Participants
- 18
RCTThe independent and combined effects of aerobic exercise and dietary fish intake on serum lipids and glycemic control in NIDDM. A randomized controlled study1997n=49
In 49 dyslipidemic NIDDM patients over 8 weeks, adding one daily fish meal (3.6 g omega-3) to a low-fat diet reduced triglycerides 0.80 mmol/L; moderate exercise improved fitness without additive glycemic harm.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 3.6 g omega-3/day
- Population
- Type 2 diabetes patients
- Participants
- 49
RCTSupplementation with n-3 fatty acids reduces triglycerides but increases PAI-1 in non-insulin-dependent diabetes mellitus1992
A 16-week (2 x 8-wk treatment period) cross-over study of 14 type 2 diabetics found that 10 g/day MaxEPA (3 g omega-3 fatty acids) led to a significant reduction in triglyceride concentrations (-27%), an increase in LDL cholesterol (+6%) no change in insulin levels and a significant increase in PAI-1 activity (+21%) after 8 weeks. [10679]
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 10 g/day
- Population
- Diabetic patients
KombuchaView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- A small study found that kombucha did not reduce blood sugar levels compared to placebo.
Browse 1 study
RCTKombucha tea as an anti-hyperglycemic agent in humans with diabetes - a randomized controlled pilot investigation2023n=12
In 12 adults with type 2 diabetes, kombucha tea for 4 weeks lowered fasting blood glucose versus baseline with acceptable tolerability in a randomized crossover study.
- Effect
- Benefit
- Duration
- 4 weeks
- Dose
- 240 mL/day
- Population
- Adults
- Participants
- 12
KudzuView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is not clear if kudzu helps with diabetes.
- An early study in adults with type 2 diabetes found that taking a kudzu component called puerarin along with a diabetes medicine for 12 weeks lowered blood sugar and a blood test called HbA1c.
- The effect of kudzu by itself is unknown, and the study had limitations.
Browse 1 study
RCT[Puerarin combined with avandia for diabetic nephropathy]2012n=180
In 180 diabetic nephropathy patients, combined puerarin plus rosiglitazone improved urinary albumin and renal function markers more than rosiglitazone alone over 12 weeks.
- Effect
- Benefit
- Duration
- 12 weeks
- Population
- Patients with diabetes
- Participants
- 180
L-CitrullineView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- In people with type 2 diabetes taking metformin and sulfonylurea medications, a small study showed that adding 3 grams of L-citrulline daily before breakfast for 8 weeks lowered fasting blood sugar by about 22 mg/dL and reduced HbA1c by 0.7%.
- L-citrulline did not change cholesterol or other blood fats.
Browse 2 studies
RCTThe impact of L-citrulline supplementation on glucose homeostasis, lipid profile, and some inflammatory factors in overweight and obese patients with type 2 diabetes: A double-blind randomized placebo-controlled trial2021n=54
In 54 overweight or obese type 2 diabetes patients, 3 g/day L-citrulline for 8 weeks improved glucose homeostasis and reduced TNF-α and hs-CRP versus placebo.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 3 g/day
- Population
- Diabetic patients
- Participants
- 54
RCTOxidative stress and nitrate/nitrite (NOx) status following citrulline supplementation in type 2 diabetes: a randomised, double-blind, placebo-controlled trial2020n=45
In 54 type 2 diabetes patients, 3 g/day citrulline for 2 months improved oxidative stress markers and nitrite/nitrate levels versus placebo.
- Effect
- Benefit
- Duration
- 2 months
- Dose
- 3 g
- Population
- Diabetic patients
- Participants
- 45
Red Yeast RiceView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Red yeast rice has insufficient evidence for Type 2 diabetes.
Browse 1 study·1 meta-analysis
RCTXuezhikang Capsule for Type 2 Diabetes with Hyperlipemia: A Systematic Review and Meta-Analysis of Randomized Clinical Trails2015n=1,548
A meta-analysis of 21 RCTs (1,548 type 2 diabetics with hyperlipidemia) found Xuezhikang improved lipids and was generally safe over at least 8 weeks of treatment.
- Effect
- Benefit
- Duration
- 8 weeks
- Population
- Diabetic patients
- Participants
- 1,548
- Ages
- 40–85
Whey ProteinView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It’s unclear whether whey protein helps manage blood sugar in people with type 2 diabetes.
- In one small study, drinking a 220 kcal beverage with 50 grams of whey protein before a meal lowered blood sugar by 28% and raised insulin levels over the next 3 hours compared with water.
- But taking 20 grams of whey protein daily for 10 weeks during an exercise program didn’t improve blood sugar control or body composition compared with no whey protein.
Browse 2 studies
RCTNil Whey Protein Effect on Glycemic Control after Intense Mixed-Mode Training in Type 2 Diabetes2018n=24
In an RCT of 24 participants, 20 g, for 10 weeks, a clinically meaningful enhancement in glycemic control after 10 wk of MMIT was not clearly advanced with peritraining whey protein supplementation in middle-age men with T2D.
- Effect
- No Benefit
- Duration
- 10 weeks
- Dose
- 20 g
- Population
- Adults
- Participants
- 24
- Avg age
- ~56
RCTIncretin, insulinotropic and glucose-lowering effects of whey protein pre-load in type 2 diabetes: a randomised clinical trial2014n=15
In an RCT of 15 participants, 50 g whey protein preload, dipeptidyl peptidase 4 plasma activity did not display any significant difference after breakfast between the groups.
- Effect
- Benefit
- Dose
- 50 g whey protein preload
- Population
- Adults
- Participants
- 15
AshwagandhaView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is uncertain if ashwagandha helps with type 2 diabetes.
- Early research suggests that taking 3 grams daily for 30 days lowered blood sugar levels similar to diabetes medications, but it was not directly compared to those drugs.
Browse 1 study
Controlled trialHypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) root2000
In 6 mild type 2 diabetics and 6 mild hypercholesterolemic subjects, ashwagandha root powder for 30 days showed hypoglycemic, diuretic, and cholesterol-lowering effects without adverse events.
- Effect
- Benefit
- Duration
- 30 days
Branched Chain Amino Acids (BCAAs)View supplement →
Reconsider purchase·★★★★★
How we scored this▸
- The research is not clear whether eating more branched-chain amino acids (BCAAs) lowers or raises the risk of developing diabetes.
- Some studies in Japanese women suggest eating more BCAAs might reduce diabetes risk, while others in US populations show the opposite, that higher BCAA intake is linked to a higher risk of diabetes.
- This may be due to different eating habits or gut bacteria among people.
- BCAAs in the blood are often higher in people who develop diabetes, but it’s uncertain if eating BCAAs causes this.
- More research is needed.
Browse 3 studies
ObservationalDietary Intakes of Branched-Chained Amino Acid and Risk for Type 2 Diabetes in Adults: The Harbin Cohort Study on Diet, Nutrition and Chronic Non-Communicable Diseases Study2018n=1,804
A cohort study of 1,804 Chinese adults found higher dietary BCAA intake was associated with greater type 2 diabetes odds, with associations varying by dietary pattern.
- Effect
- No Benefit
- Population
- Adults
- Participants
- 1,804
MetaCumulative consumption of branched-chain amino acids and incidence of type 2 diabetes2016
Pooled data from three Western cohorts with 16,097 incident diabetes cases found highest-quintile dietary BCAA intake raised type 2 diabetes risk about 11–13% per amino acid.
- Effect
- No Benefit
- Population
- Adults
Branched-chain amino acid intake and the risk of diabetes in a Japanese community: the Takayama study2013
In 13,525 Japanese adults, higher dietary BCAA intake was associated with lower diabetes risk in women (HR 0.57, highest vs lowest tertile) and a marginal association in men.
- Effect
- Benefit
- Population
- Women
Ceylon CinnamonView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Most research shows that Ceylon cinnamon does not consistently help lower blood sugar in people with type 2 diabetes.
- Taking 1 to 9 grams daily for a few months usually does not improve fasting blood sugar.
- Some smaller studies suggest it might help people with poorly controlled diabetes, but the evidence is limited and not clear.
- One larger study found small improvements compared to placebo, but it’s unclear if medicine changes affected results.
- More research is needed to know if cinnamon can be helpful for diabetes management.
Browse 5 studies
RCTEfficacy of Young Cinnamomum zeylanicum Blume Bark on Hyperglycemia and PTPase Activity in Type 2 Diabetes2023
In 154 type 2 diabetes patients, 1.5 g/day Ceylon cinnamon for 120 days reduced fasting glucose by 35.5% versus a 5% rise with placebo and inhibited PTP1B expression in peripheral blood cells.
- Effect
- Benefit
- Duration
- 120 days
- Dose
- 1.5 g/day
- Population
- Diabetic patients
RCTEffects of Cinnamon Consumption on Glycemic Indicators, Advanced Glycation End Products, and Antioxidant Status in Type 2 Diabetic Patients2017n=22
In 44 type 2 diabetes patients, 3 g/day cinnamon for 8 weeks did not significantly change fasting glucose, HbA1c, HOMA-IR, or inflammatory markers versus placebo.
- Effect
- No Benefit
- Duration
- 8 weeks
- Dose
- 3 g/day
- Population
- Diabetic patients
- Participants
- 22
- Avg age
- ~57
RCTControlling type 2 diabetes mellitus with herbal medicines: A triple-blind randomized clinical trial of efficacy and safety2016
In 105 type 2 diabetes patients, 1 g/day cinnamon for 90 days improved BMI versus placebo but did not differ from whortleberry on glucose, insulin sensitivity, or lipids between herb groups.
- Effect
- No Benefit
- Duration
- 90 days
- Dose
- 1 g/day
- Population
- Diabetic patients
RCTEffects of Cinnamon, Cardamom, Saffron, and Ginger Consumption on Markers of Glycemic Control, Lipid Profile, Oxidative Stress, and Inflammation in Type 2 Diabetes Patients2014n=204
In 204 type 2 diabetes patients, 3 g/day cinnamon with black tea for 8 weeks improved cholesterol markers versus controls, but only within-group cinnamon intake significantly lowered fasting blood sugar.
- Effect
- No Benefit
- Duration
- 8 weeks
- Dose
- 3 g/day
- Population
- Diabetic patients
- Participants
- 204
RCTEffects of cinnamon consumption on glycemic status, lipid profile and body composition in type 2 diabetic patients2012n=22
In 44 type 2 diabetes patients, 3 g/day cinnamon for 8 weeks improved fasting glucose, HbA1c, triglycerides, weight, BMI, and body fat within the treatment group, with no significant between-group differences at endpoint.
- Effect
- No Benefit
- Duration
- 8 weeks
- Dose
- 3 g/day
- Population
- Diabetic patients
- Participants
- 22
- Ages
- 30–65
LysineView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- A small study shows that taking lysine supplements (500 mg twice a day for 2 months) did not change blood sugar or long-term blood sugar levels in people with type 2 diabetes, when compared to a control group.
Browse 1 study
Controlled trialEffect of oral supplementation of free amino acids in type 2 diabetic patients-- a pilot clinical trial2002n=77
A 2-month double-blind pilot of 77 type 2 diabetes patients found oral amino acid supplementation (including lysine) modestly reduced postprandial glucose without changing insulin levels.
- Effect
- Benefit
- Duration
- 2 months
- Population
- Adults
- Participants
- 77
- Ages
- 30–60
SeleniumView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Taking too much selenium, from food or supplements, may increase the chance of developing type 2 diabetes.
- Studies suggest that both low and high selenium levels can raise diabetes risk.
- People who consume more than the recommended amount might have a higher risk than those who consume less.
- Some studies found selenium supplements help the body use insulin better but don’t lower blood sugar.
- For pregnant women with gestational diabetes, selenium with diet slightly lowered blood sugar.
- It’s important to keep selenium intake balanced because too little or too much may impact diabetes risk.
Browse 3 studies·2 meta-analyses
MetaPotential Benefits of Selenium Supplementation in Reducing Insulin Resistance in Patients with Cardiometabolic Diseases: A Systematic Review and Meta-Analysis2022n=526
A meta-analysis of 10 cardiometabolic disease RCTs (526 patients) found selenium supplementation reduced insulin and HOMA-IR and raised HDL cholesterol.
- Effect
- Benefit
- Population
- Patients with cardiometabolic diseases
- Participants
- 526
MetaSelenium exposure and the risk of type 2 diabetes: a systematic review and meta-analysis2018
A meta-analysis of 50 studies found higher selenium exposure associated with increased type 2 diabetes risk, and 200 mcg/day supplementation trials also showed elevated diabetes risk.
- Effect
- No Benefit
- Dose
- 200 mcg/day
- Population
- Patients with type 2 diabetes
RCTSelenium Supplementation for Prevention of Colorectal Adenomas and Risk of Associated Type 2 Diabetes2016n=1,621
In 1374 participants from the Sel/Cel trial, selenium 200 mcg/day for up to 33 months did not reduce colorectal adenoma recurrence versus placebo.
- Effect
- No Benefit
- Duration
- 33 months
- Dose
- 200 mcg/day
- Population
- Adults
- Participants
- 1,621
- Ages
- 40–80
ZeaxanthinView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Taking zeaxanthin likely does not help prevent diabetes or its complications.
- Studies show that low levels of zeaxanthin and lutein in the blood are linked to problems with blood sugar control.
- However, eating more zeaxanthin and lutein does not reduce the chance of getting type 2 diabetes.
- In people who already have diabetes, higher blood zeaxanthin does not lower the risk of heart-related death.
Browse 4 studies·1 meta-analysis
ObservationalAssociations of Serum Carotenoids With Risk of Cardiovascular Mortality Among Individuals With Type 2 Diabetes: Results From NHANES2022n=3,107
In 3,107 adults with type 2 diabetes, higher serum beta-carotene was associated with increased cardiovascular mortality (HR 2.47 top vs bottom quartile); lutein/zeaxanthin showed no significant association.
- Effect
- No Benefit
- Duration
- 14 years
- Population
- Adults
- Participants
- 3,107
MetaThe effects of lutein on cardiometabolic health across the life course: a systematic review and meta-analysis2016n=387,569
A systematic review and meta-analysis found lutein intake inversely associated with some cardiometabolic outcomes but evidence varied by life stage and endpoint.
- Effect
- No Benefit
- Population
- Pregnant women
- Participants
- 387,569
ObservationalDiabetes mellitus and serum carotenoids: findings of a population-based study in Queensland, Australia2005n=1,597
In 1,597 Australian adults, serum lutein/zeaxanthin and other carotenoids except lycopene were inversely associated with type 2 diabetes and impaired glucose metabolism.
- Effect
- Benefit
- Population
- Adults
- Participants
- 1,597
- Ages
- ≥25
ObservationalDietary antioxidant intake and risk of type 2 diabetes2004n=2,285
In 4,304 Finnish adults followed 23 years, higher beta-cryptoxanthin intake was associated with reduced type 2 diabetes risk (RR 0.58); vitamin E showed the strongest antioxidant association.
- Duration
- 23 years
- Population
- Patients with type 2 diabetes
- Participants
- 2,285
- Ages
- 40–69
IronView supplement →
Do not purchase·★★★★★
How we scored this▸
- Early research on type 2 diabetes is limited.
- A systematic review and dose-response meta-analysis evaluating the association between dietary iron intake and the risk of developing type 2 diabetes across prospective cohort studies.
- More studies are needed before any benefit can be considered reliable.
Browse 1 study·1 meta-analysis
MetaDietary iron intake and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis of prospective cohort studies2022n=11
A dose-response meta-analysis of 11 cohorts (323,788 participants) found each 1 mg/day increase in dietary heme iron was associated with 16% higher type 2 diabetes risk; total or non-heme iron showed no association.
- Effect
- No Benefit
- Dose
- 1 mg/day
- Participants
- 11
ReishiView supplement →
Do not purchase·★★★★★
How we scored this▸
- Research on reishi mushroom for type 2 diabetes shows mixed results.
- Most studies found no benefit on blood sugar or cholesterol levels.
- One small study found that a specific reishi extract (Ganopoly) lowered long-term blood sugar (HbA1c) but did not affect fasting blood sugar.
Browse 2 studies·1 meta-analysis
MetaGanoderma lucidum mushroom for the treatment of cardiovascular risk factors2015n=398
A meta-analysis of 5 RCTs (398 adults) found Ganoderma lucidum 1.4–3 g/day for 12–16 weeks did not significantly improve blood glucose, blood pressure, or lipids versus control.
- Effect
- No Benefit
- Duration
- 12–16 weeks
- Dose
- 3 g/day
- Population
- Adults
- Participants
- 398
A Phase I/II Study of Ling Zhi Mushroom Ganoderma lucidum (W.Curt.:Fr.)Lloyd (Aphyllophoromycetideae) Extract in Patients with Type II Diabetes Mellitus2004
A phase I/II trial of Ganoderma lucidum extract in type 2 diabetes patients; no abstract text was available to report specific outcomes.
- Effect
- Benefit
- Population
- Patients with Type II Diabetes Mellitus
Acetyl-L-CarnitineView supplement →
Do not purchase·★★★★★
How we scored this▸
- Taking acetyl-L-carnitine by mouth does not seem to help control blood sugar in type 2 diabetes.
- A study found no improvement in blood sugar or insulin measures after 6 months of taking acetyl-L-carnitine.
- Most people in the study were already on diabetes and heart medications.
- It's unknown if acetyl-L-carnitine helps people with poorly controlled diabetes.
Browse 1 study
RCTBlood pressure and metabolic effects of acetyl-L-carnitine in type 2 diabetes: DIABASI randomized controlled trial2018n=29
The DIABASI RCT in 229 hypertensive type 2 diabetes patients found acetyl-L-carnitine 1000 mg twice daily for 6 months did not improve blood pressure, glycemic control, lipids, or insulin sensitivity versus placebo on statin therapy.
- Effect
- No Benefit
- Duration
- 6 months
- Dose
- 1000 mg 2×/day
- Population
- Diabetic patients
- Participants
- 29
- Ages
- 40+
Black TeaView supplement →
Do not purchase·★★★★★
How we scored this▸
- Early research shows that taking a black and green tea extract every day for 3 months does not improve blood sugar control in people with diabetes.
- Large studies in Japanese adults also suggest that drinking at least 1 cup of black tea daily does not lower the risk of developing type 2 diabetes compared with drinking less than 1 cup a day.
Browse 2 studies
RCTThe effect of an extract of green and black tea on glucose control in adults with type 2 diabetes mellitus: double-blind randomized study2007n=49
In 49 type 2 diabetic adults, 3 months of green/black tea extract (375 or 750 mg/day) did not lower HbA1c versus placebo; mean HbA1c rose ~0.3–0.5% in all arms.
- Effect
- No Benefit
- Duration
- 3 months
- Dose
- 750 mg/day
- Population
- Adults
- Participants
- 49
- Avg age
- ~65
ObservationalThe relationship between green tea and total caffeine intake and risk for self-reported type 2 diabetes among Japanese adults2006n=231
In 17,413 Japanese adults aged 40–65 followed 5 years, ≥6 cups/day green tea (OR 0.67) and ≥3 cups/day coffee (OR 0.58) were inversely associated with self-reported type 2 diabetes; black or oolong tea were not.
- Effect
- No Benefit
- Population
- Adults
- Participants
- 231
- Ages
- 40–65
Oleic AcidView supplement →
Do not purchase·★★★★★
How we scored this▸
- It is unclear if taking oleic acid helps people with diabetes.
- A small study in type 2 diabetes showed that taking oleic acid as part of a low-fat diet for 3 weeks did not change cholesterol levels compared to taking another type of fat called linoleic acid.
Browse 1 study
RCTEffect of a low-fat diet enriched with oleic acid on postprandial lipemia in patients with type 2 diabetes mellitus2001
In 8 type 2 diabetic patients, a 3-week low-fat diet enriched with oleic acid increased postprandial remnant lipoprotein cholesterol after an oral fat load vs linoleic-acid-enriched diet.
- Effect
- No Benefit
- Population
- Diabetic patients
Evidence visualised
Same ratings as above, aggregated so you can see coverage and imbalance.
| Supplement | DEX | Studies | Meta-analyses | Share |
|---|---|---|---|---|
| Chromium | ★★★★★68% | 42 | 9 | 10% |
| L-Carnitine | ★★★★★68% | 25 | 6 | 6% |
| Resveratrol | ★★★★★68% | 24 | 19 | 6% |
| Cassia Cinnamon | ★★★★★68% | 21 | 7 | 5% |
| Magnesium | ★★★★★68% | 21 | 9 | 5% |
| Fish Oil | ★★★★★44% | 18 | 5 | 4% |
| Green Tea | ★★★★★56% | 15 | 6 | 3% |
| Alpha-Lipoic Acid | ★★★★★52% | 14 | 1 | 3% |
| Caffeine | ★★★★★68% | 14 | 2 | 3% |
| Vitamin D | ★★★★★56% | 12 | 7 | 3% |
| Aloe | ★★★★★56% | 11 | 3 | 3% |
| Oats | ★★★★★68% | 11 | 2 | 3% |
| Berberine | ★★★★★68% | 10 | 5 | 2% |
| Beta-Glucan | ★★★★★76% | 9 | 2 | 2% |
| Curcumin | ★★★★★72% | 9 | 5 | 2% |
| Flaxseed | ★★★★★72% | 8 | 4 | 2% |
| Flaxseed Oil | ★★★★★52% | 8 | 2 | 2% |
| Milk Thistle | ★★★★★72% | 8 | 2 | 2% |
| Nattokinase | ★★★★★72% | 8 | 5 | 2% |
| Panax Ginseng | ★★★★★72% | 8 | 3 | 2% |
| Apple Cider Vinegar | ★★★★★72% | 7 | 3 | 2% |
| Cocoa | ★★★★★52% | 7 | 3 | 2% |
| Inulin | ★★★★★72% | 7 | 3 | 2% |
| Vitamin K | ★★★★★52% | 7 | 4 | 2% |
| Melatonin | ★★★★★52% | 6 | 3 | 1% |
| Biotin | ★★★★★52% | 5 | 1 | 1% |
| Ceylon Cinnamon | ★★★★★40% | 5 | 0 | 1% |
| Garlic | ★★★★★72% | 5 | 1 | 1% |
| Ginger | ★★★★★52% | 5 | 4 | 1% |
| Taurine | ★★★★★72% | 5 | 1 | 1% |
| Vitamin B9 (Folate) | ★★★★★52% | 5 | 3 | 1% |
| American Ginseng | ★★★★★48% | 4 | 0 | <1% |
| Ivy Gourd | ★★★★★60% | 4 | 0 | <1% |
| Jiaogulan | ★★★★★72% | 4 | 1 | <1% |
| Lutein | ★★★★★52% | 4 | 1 | <1% |
| Zeaxanthin | ★★★★★40% | 4 | 1 | <1% |
| Zinc | ★★★★★72% | 4 | 2 | <1% |
| Astragalus | ★★★★★52% | 3 | 3 | <1% |
| Branched Chain Amino Acids (BCAAs) | ★★★★★40% | 3 | 0 | <1% |
| Kefir | ★★★★★52% | 3 | 1 | <1% |
| Lycopene | ★★★★★52% | 3 | 1 | <1% |
| Olive Oil | ★★★★★68% | 3 | 3 | <1% |
| Quercetin | ★★★★★48% | 3 | 0 | <1% |
| Selenium | ★★★★★40% | 3 | 2 | <1% |
| Bilberry | ★★★★★44% | 2 | 0 | <1% |
| Black Tea | ★★★★★32% | 2 | 0 | <1% |
| Boswellia | ★★★★★48% | 2 | 2 | <1% |
| Casein Protein | ★★★★★44% | 2 | 0 | <1% |
| Ginkgo | ★★★★★48% | 2 | 1 | <1% |
| L-Citrulline | ★★★★★44% | 2 | 0 | <1% |
| Reishi | ★★★★★36% | 2 | 1 | <1% |
| Whey Protein | ★★★★★44% | 2 | 0 | <1% |
| Acetyl-L-Carnitine | ★★★★★32% | 1 | 0 | <1% |
| Ashwagandha | ★★★★★40% | 1 | 0 | <1% |
| Astaxanthin | ★★★★★44% | 1 | 0 | <1% |
| Beta-Alanine | ★★★★★64% | 1 | 1 | <1% |
| Eleuthero | ★★★★★44% | 1 | 0 | <1% |
| Iron | ★★★★★36% | 1 | 1 | <1% |
| Kombucha | ★★★★★44% | 1 | 0 | <1% |
| Kudzu | ★★★★★44% | 1 | 0 | <1% |
| Lysine | ★★★★★40% | 1 | 0 | <1% |
| Oleic Acid | ★★★★★32% | 1 | 0 | <1% |
| Potassium | ★★★★★48% | 1 | 1 | <1% |
| Probiotics | ★★★★★64% | 1 | 1 | <1% |
| Red Yeast Rice | ★★★★★44% | 1 | 1 | <1% |
| Yerba Mate | ★★★★★56% | 1 | 0 | <1% |