Kidney failure
Supplements studied for kidney failure.
Overview
Calcium carbonate and calcium acetate have the strongest evidence for kidney failure, with high ratings across effect size, evidence, and trust. These may help lower elevated blood phosphate levels, with calcium acetate appearing more effective than sevelamer in some studies. Calcium citrate is not advised because it binds phosphate less well.
L-Carnitine has medium-strength evidence from 27 studies, though oral use is not FDA-approved and results for dialysis-related problems such as anemia response, cramps, and blood pressure are mixed. Selenium, Vitamin B9 (Folate), and N-Acetyl Cysteine (NAC) have limited or uncertain evidence. The heatmap and evidence reviews below provide a fuller comparison.
Effect graph
Relevant supplements
Relevant supplements sorted by DEX Score.
| Calcium | ★★★★★ | High |
| L-Carnitine | ★★★★★ | Medium |
| Vitamin K | ★★★★★ | Low |
| Vitamin B9 (Folate) | ★★★★★ | Low |
| N-Acetyl Cysteine (NAC) | ★★★★★ | Low |
| Selenium | ★★★★★ | Very Low / None |
Studies
Find individual evidence reviews for supplements sorted by DEX Score.
6 supplements for , and rated at least stars. All purchase bands. No minimum star filter.
CalciumView supplement →
Consider purchase·★★★★★
How we scored this▸
- For people with kidney failure, calcium carbonate and calcium acetate can be taken by mouth to help lower high phosphate levels in the blood.
- Calcium acetate (sometimes sold as PhosLo) seems to work better at controlling phosphate than another medicine called sevelamer (Renagel).
- Calcium citrate is not advised because it doesn’t bind phosphate as well and can cause the body to absorb more aluminum, which may be harmful.
- Some studies also show that calcium supplements may help lower blood pressure in people with kidney failure.
Browse 6 studies
ObservationalRelationship of serum calcium concentration with chronic kidney disease and mortality in type 2 diabetes mellitus patients: evidence from the NHANES 1999-20182025
In 6,595 NHANES adults with type 2 diabetes, serum calcium levels showed complex associations with diabetic kidney disease and mortality across stratified analyses.
- Population
- Diabetic patients
- Ages
- 40+
Systematic reviewBenefits and harms of phosphate binders in CKD: a systematic review of randomized controlled trials2009n=6,406
A systematic review of 40 CKD phosphate-binder trials (6,406 patients) found calcium salts lowered phosphorus and PTH vs sevelamer but increased hypercalcemia risk; mortality effects were unclear.
- Effect
- Benefit
- Population
- CKD patients
- Participants
- 6,406
A comparison of clinically useful phosphorus binders for patients with chronic kidney failure2004
A review compared phosphate binders in CKD, noting calcium carbonate and acetate effectively lower phosphorus but carry hypercalcemia and vascular calcification concerns.
- Population
- CKD patients
RCTTreatment of hyperphosphatemia in hemodialysis patients: The Calcium Acetate Renagel Evaluation (CARE Study)2004
In 100 hemodialysis patients over 8 weeks, calcium acetate achieved phosphorus and calcium-phosphate product targets more often than sevelamer, with transient hypercalcemia in 17%.
- Effect
- Benefit
- Duration
- 8 weeks
- Dose
- 1.08 mg/day
- Population
- Hemodialysis patients
RCTLong-term oral calcium supplementation reduces diastolic blood pressure in end stage renal disease. A randomized, double-blind, placebo controlled study1994n=11
In 11 hemodialysis patients over 6 months, 2 g/day calcium lowered diastolic BP ~7 mmHg vs placebo while treating secondary hyperparathyroidism.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 2 g/day
- Population
- CKD patients
- Participants
- 11
Controlled trialCalcium citrate markedly enhances aluminum absorption from aluminum hydroxide1991
In 8 healthy men, calcium citrate markedly increased urinary aluminum absorption when co-ingested with aluminum hydroxide, raising concern about combined antacid use.
- Effect
- No Benefit
- Duration
- 3 days
- Dose
- 3 g/day
- Population
- Patients with chronic renal failure
L-CarnitineView supplement →
Consider purchase·★★★★★
How we scored this▸
- For people on dialysis due to kidney failure, intravenous L-carnitine is FDA-approved to treat low L-carnitine levels.
- Oral L-carnitine is not approved for this use and may cause buildup of harmful byproducts in people with kidney disease.
- Some research suggests L-carnitine may help with certain dialysis-related problems, such as low red blood cell response to therapy, low blood pressure during dialysis, muscle cramps, and heart or inflammation markers.
- But the results are mixed, benefits are usually modest, and many studies are low quality.
- L-carnitine does not reliably improve cholesterol levels, exercise ability, or overall quality of life in dialysis patients.
Browse 27 studies·7 meta-analyses
MetaThe effect of levocarnitine supplementation on dialysis-related hypotension: A systematic review, meta-analysis, and trial sequential analysis2022n=224
A meta-analysis found levocarnitine supplementation reduced dialysis-related hypotension episodes in hemodialysis patients versus control.
- Effect
- Benefit
- Dose
- 200 mg/day
- Population
- Hemodialysis patients
- Participants
- 224
MetaThe Effect of Non-Pharmacological and Pharmacological Interventions on Measures Associated with Sarcopenia in End-Stage Kidney Disease: A Systematic Review and Meta-Analysis2022
A meta-analysis in end-stage kidney disease found pharmacological and non-pharmacological interventions including carnitine modestly improved sarcopenia-related measures versus control.
- Effect
- Benefit
- Population
- Adults
RCTEffect of L-carnitine supplementation on lipid profile and apolipoproteins in children on hemodialysis: a randomized placebo-controlled clinical trial2021n=12
In 12 pediatric CKD patients, L-carnitine 50 mg/kg/day for 10 weeks improved lipid profile and apolipoproteins versus baseline.
- Effect
- Benefit
- Duration
- 10 weeks
- Dose
- 50 mg/kg
- Population
- Children/adolescents
- Participants
- 12
- Ages
- 6–18
MetaEffect of L-carnitine supplementation on renal anemia in patients on hemodialysis: a meta-analysis2021n=1,090
A meta-analysis of 1,090 hemodialysis patients found L-carnitine improved hemoglobin and reduced erythropoietin dose requirements versus control.
- Effect
- Benefit
- Population
- Hemodialysis patients
- Participants
- 1,090
Clinical trialEffects of L-Carnitine Supplementation in Patients Receiving Hemodialysis or Peritoneal Dialysis2020n=80
In 80 dialysis patients, L-carnitine 600 mg/day for 24 months improved muscle carnitine stores and reduced fatigue versus baseline.
- Effect
- Benefit
- Duration
- 24 months
- Dose
- 600 mg/day
- Population
- Dialysis patients
- Participants
- 80
- Avg age
- ~62±15
RCTl-carnitine supplementation vs cycle ergometer exercise for physical activity and muscle status in hemodialysis patients: A randomized clinical trial2020n=20
In 20 hemodialysis patients, L-carnitine 1,000 mg/day for 3 months improved physical activity and muscle function versus cycle ergometer exercise alone.
- Effect
- Benefit
- Duration
- 3 months
- Dose
- 1000 mg/day
- Population
- Women
- Participants
- 20
- Avg age
- 55.5±13.8
MetaEffect of L-carnitine therapy on patients in maintenance hemodialysis: a systematic review and meta-analysis2014
A systematic review found L-carnitine in maintenance hemodialysis improved anemia parameters and exercise tolerance, though mortality effects were uncertain.
- Effect
- Benefit
- Population
- Hemodialysis patients
MetaL-Carnitine supplementation for adults with end-stage kidney disease requiring maintenance hemodialysis: a systematic review and meta-analysis2014n=1,734
A meta-analysis of 1,734 maintenance hemodialysis patients found L-carnitine increased hemoglobin and reduced required erythropoietin dose versus control.
- Effect
- Benefit
- Population
- Adults
- Participants
- 1,734
MetaInfluence of L-carnitine supplementation on serum lipid profile in hemodialysis patients: a systematic review and meta-analysis2013n=391
A meta-analysis of 391 hemodialysis patients found L-carnitine improved serum lipid profiles versus control, with modest triglyceride reduction.
- Effect
- Benefit
- Population
- Adults
- Participants
- 391
RCTL-carnitine treatment in incident hemodialysis patients: the multicenter, randomized, double-blinded, placebo-controlled CARNIDIAL trial2012
In incident hemodialysis patients, L-carnitine for 1 year improved carnitine status and anemia management versus control in a multicenter RCT.
- Effect
- No Benefit
- Duration
- 1 year
- Dose
- 1 g/day
- Population
- Dialysis patients
RCTEffects of carnitine and coenzyme Q10 on lipid profile and serum levels of lipoprotein(a) in maintenance hemodialysis patients on statin therapy2011n=27
In 27 hemodialysis patients, carnitine plus coenzyme Q10 improved lipid profile and Lp(a) versus baseline over the supplementation period.
- Effect
- Benefit
- Dose
- 4 g/day
- Population
- Dialysis patients
- Participants
- 27
RCTThe effect of L-carnitine supplementation on lipid parameters, inflammatory and nutritional markers in maintenance hemodialysis patients2011n=35
In 35 maintenance hemodialysis patients, L-carnitine for 2–5 years improved lipid and inflammatory markers versus baseline alongside standard dialysis care.
- Effect
- Benefit
- Dose
- 1 g/day
- Population
- Kidney disease patients
- Participants
- 35
- Ages
- 2–5
RCTEffects of L-carnitine supplement on serum inflammatory cytokines, C-reactive protein, lipoprotein (a), and oxidative stress in hemodialysis patients with Lp (a) hyperlipoproteinemia2010n=23
In 23 hemodialysis patients, L-carnitine 1,000 mg/day for 12 weeks reduced CRP and inflammatory cytokines versus baseline.
- Effect
- Benefit
- Duration
- 12 weeks
- Dose
- 1000 mg/day
- Population
- Hemodialysis patients with hyperlipoproteinemia (a)
- Participants
- 23
The effects of L-carnitine therapy on respiratory function tests in chronic hemodialysis patients2010
In chronic hemodialysis patients, L-carnitine therapy improved some respiratory function test parameters versus baseline in a clinical evaluation.
- Effect
- Benefit
- Dose
- 20 mg/kg
- Population
- Adults
Clinical trial[Study of aerobic capacity in chronic hemodialized patients: effect of L-carnitine supplementation]2008n=21
In 21 chronic hemodialysis patients, L-carnitine for 12 weeks improved aerobic capacity on exercise testing versus baseline.
- Effect
- No Benefit
- Duration
- 12 weeks
- Population
- Kidney disease patients
- Participants
- 21
- Ages
- 20–50
MetaEffects of L-carnitine on dialysis-related hypotension and muscle cramps: a meta-analysis2008n=193
A meta-analysis found L-carnitine reduced dialysis-related hypotension and muscle cramps in hemodialysis patients versus control, though evidence quality was moderate.
- Effect
- No Benefit
- Population
- Adults
- Participants
- 193
Clinical trialEffect of carnitine supplementation on lipid profile and anemia in children on chronic dialysis2007n=16
In 16 children on dialysis, carnitine 20 mg/day for 3 months improved lipid profile and erythropoietin responsiveness versus baseline.
- Effect
- No Benefit
- Duration
- 3 months
- Dose
- 20 mg/kg/day
- Population
- Children/adolescents
- Participants
- 16
ObservationalProtective effect of intravenous levocarnitine on subsequent-month hospitalization among prevalent hemodialysis patients, 1998 to 20032007
An observational study found IV levocarnitine in hemodialysis patients was associated with lower hospitalization rates in the subsequent month versus non-treated periods.
- Effect
- Benefit
- Duration
- 1 month
- Dose
- 1 g/day
- Population
- Hemodialysis patients
RCTEffects of L-carnitine infusions on inflammatory and nutritional markers in haemodialysis patients2006
In hemodialysis patients, L-carnitine infusions 20 mg/kg for 6 months reduced inflammatory and nutritional deficiency markers versus baseline.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 20 mg/kg
- Population
- Hemodialysis patients
L-carnitine supplementation in hemodialysis patients2005
A study in hemodialysis patients reported L-carnitine supplementation improved carnitine deficiency symptoms and exercise tolerance versus baseline.
- Effect
- Benefit
- Dose
- 15 mg/kg
- Population
- Adults
- Avg age
- ~48
Systematic reviewEffects of L-carnitine supplementation in maintenance hemodialysis patients: a systematic review2002n=482
A systematic review found L-carnitine supplementation in maintenance hemodialysis improved carnitine levels, anemia indices, and intradialytic symptoms versus control.
- Effect
- Benefit
- Population
- Hemodialysis patients
- Participants
- 482
RCTEvaluation of the effect of intravenous l-carnitine on quality of life in chronic hemodialysis patients2000n=16
In 16 chronic hemodialysis patients, IV L-carnitine 20 mg/kg for 12 weeks improved quality of life scores versus baseline.
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 20 mg/kg
- Population
- Chronic hemodialysis patients
- Participants
- 16
- Ages
- 18+
RCTCarnitine status of pediatric patients on continuous ambulatory peritoneal dialysis1990
In 12 pediatric CAPD patients, oral carnitine 100 mg/kg for 2 months improved plasma carnitine and lowered triglycerides versus baseline.
- Effect
- No Benefit
- Duration
- 2 months
- Dose
- 100 mg/kg
- Population
- Children/adolescents
RCTL-carnitine and platelet aggregation in uremic patients subjected to hemodialysis1990
In hemodialysis patients, oral L-carnitine 3 g/day increased platelet aggregation and serum triglycerides versus baseline, raising potential cardiovascular concerns.
- Effect
- No Benefit
- Dose
- 3 g/day
- Population
- Hemodialysis patients
RCTMulticenter trial of L-carnitine in maintenance hemodialysis patients. I. Carnitine concentrations and lipid effects1990n=38
A multicenter hemodialysis trial (38 patients) found L-carnitine 20 mg/day improved plasma carnitine but had inconsistent effects on lipids versus control.
- Effect
- No Benefit
- Dose
- 20 mg/kg/day
- Population
- Kidney disease patients
- Participants
- 38
RCTThe effect of L-carnitine on lipid metabolism in patients on chronic haemodialysis1987n=10
In 21 chronic hemodialysis patients, L-carnitine for 6 months improved hyperlipoproteinemia markers versus control in a clinical trial.
- Effect
- No Benefit
- Duration
- 6 months
- Population
- Hemodialysis patients
- Participants
- 10
- Ages
- 20–72
Controlled trialPlasma lipoproteins, liver function and glucose metabolism in haemodialysis patients: lack of effect of L-carnitine supplementation1985n=14
In 14 hemodialysis patients, IV L-carnitine 2 g for 6 weeks improved lipid metabolism and glucose handling versus baseline.
- Effect
- No Benefit
- Duration
- 6 weeks
- Dose
- 2 g/day
- Population
- Dialysis patients
- Participants
- 14
N-Acetyl Cysteine (NAC)View supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Taking N-acetylcysteine (NAC) by mouth may lower the chance of heart attacks and strokes in people with kidney failure on dialysis.
- One study found NAC reduced these events by about 40%, but it did not reduce the overall death rate.
Browse 1 study
RCTThe antioxidant acetylcysteine reduces cardiovascular events in patients with end-stage renal failure: a randomized, controlled trial2003n=134
A randomized trial of 134 hemodialysis patients found acetylcysteine (600 mg twice daily) significantly reduced cardiovascular events over median 14.5 months versus placebo.
- Effect
- Benefit
- Duration
- up to 24 months
- Dose
- 600 mg 2×/day
- Population
- Hemodialysis patients
- Participants
- 134
- Avg age
- ~62
Vitamin B9 (Folate)View supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is uncertain whether folic acid supplements benefit people with kidney failure.
- A study in Taiwan found that people on dialysis who took folic acid daily had a lower risk of blood clots in their dialysis access than those taking it weekly, but daily folic acid did not lower heart disease, cancer, or death risk.
- Another small study showed that taking high doses of folic acid with vitamin B1 for almost two years lowered death rates and improved thinking skills in dialysis patients, but it’s unclear which vitamin caused these benefits.
Browse 2 studies
ObservationalSupplementation with Folic Acid and Cardiovascular Outcomes in End-Stage Kidney Disease: A Multi-Institution Cohort Study2022
An observational study in patients with eskd found that the mean follow-up time was 5.8 years, and the event rates of arteriovenous access thrombosis were 17.0% and 23.6% in the daily and weekly folic acid supplementation groups (sub-distribution hazard ratio = 0.69, 95% confidence interval = 0.61 to 0.77), respectively.
- Effect
- Benefit
- Dose
- 5 mg/day
- Population
- Patients With Eskd
RCTA pilot study of thiamin and folic acid in hemodialysis patients with cognitive impairment2021n=25
A randomized trial of 25 mci patients found that 90 mg/day for 96 weeks the proportion of adverse events in treatment group was significantly lower than that in control group.
- Effect
- Benefit
- Duration
- 96 weeks
- Dose
- 90 mg/day
- Population
- MCI patients
- Participants
- 25
- Ages
- 18–80
Vitamin KView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- It is not clear if taking vitamin K2 by mouth helps with muscle cramps in adults with kidney failure.
- Early research in people on regular dialysis who have hard-to-treat muscle cramps found that taking 360 micrograms of vitamin K2 daily for 8 weeks helped reduce how often and how bad the cramps were, as well as how long they lasted, compared to those who took a placebo.
Browse 1 study
RCTVitamin K2 as a potential therapeutic candidate for the prevention of muscle cramps in hemodialysis patients: A prospective multicenter, randomized, controlled, crossover pilot trial2022n=523
In an RCT of 523 participants, 360 µg/day, this pilot trial demonstrated that vitamin K2 supplementation could decrease the frequency, duration, and severity of muscle cramps in HD patients.
- Effect
- Benefit
- Dose
- 360 mcg/day
- Population
- Dialysis patients
- Participants
- 523
SeleniumView supplement →
Do not purchase·★★★★★
How we scored this▸
- People on long-term hemodialysis often have low selenium levels and might need supplements.
- But taking selenium for 3 months does not seem to help improve cholesterol or other fat levels in the blood compared to no treatment.
Browse 3 studies
RCTEffect of selenium supplementation on lipid profile in hemodialysis patients2016n=42
In 84 selenium-deficient hemodialysis patients over 3 months, selenium supplementation raised LDL cholesterol versus placebo, with no clear lipid benefit overall.
- Effect
- No Benefit
- Duration
- 3 months
- Population
- Hemodialysis patients
- Participants
- 42
RCTCopper, selenium, zinc, and thiamine balances during continuous venovenous hemodiafiltration in critically ill patients2004n=11
In 11 critically ill patients on continuous renal replacement therapy, copper, selenium, and zinc balances were often negative relative to recommended parenteral intakes.
- Population
- Critically ill patients
- Participants
- 11
- Avg age
- ~65
ObservationalInfluence of hemodialysis on selenium blood levels2000n=95
In 95 hemodialysis patients, predialysis selenium levels were lower than controls and increased modestly after dialysis, with cuprophane membranes showing the largest post-dialysis rise.
- Population
- Healthy adults
- Participants
- 95
Evidence visualised
Same ratings as above, aggregated so you can see coverage and imbalance.
| Supplement | DEX | Studies | Meta-analyses | Share |
|---|---|---|---|---|
| L-Carnitine | ★★★★★68% | 27 | 7 | 68% |
| Calcium | ★★★★★76% | 6 | 0 | 15% |
| Selenium | ★★★★★36% | 3 | 0 | 8% |
| Vitamin B9 (Folate) | ★★★★★44% | 2 | 0 | 5% |
| N-Acetyl Cysteine (NAC) | ★★★★★44% | 1 | 0 | 3% |
| Vitamin K | ★★★★★44% | 1 | 0 | 3% |