Olive Oil
Olive oil, especially extra-virgin, is studied for cardiovascular and metabolic outcomes as part of Mediterranean-pattern diets.
Overview
What is olive oil?
Olive oil is an oil derived from the olive fruit. A Mediterranean diet staple, olive oil is rich in monounsaturated fats, mainly oleic acid, and contains antioxidants and antimicrobial compounds. Extra virgin olive oil (EVOO) is minimally processed, preserving the highest levels of beneficial nutrients. Some antioxidants in olive oil are sensitive to heat and light, so it should be stored in a cool, dark place to maintain quality. EVOO has a smoke point around 320 °F (160 °C), lower than more processed olive oils, which have higher smoke points.
Dosage
N/A
Effect graph
Effect heatmap
SupplementDEX Database
36 conditions for , and rated at least stars. All purchase bands. No minimum star filter.
Database Snapshot
Most olive oil research is concentrated in a handful of conditions.
- Cardiovascular disease accounts for 12 of 82 studies (15%).
- Dyslipidemia accounts for 8 of 82 studies (10%).
- Breast cancer accounts for 5 of 82 studies (6%).
- Sparse coverage remains for Eczema, Mild cognitive impairment, Oral health.
Dietary Sources
Dietary sources
Olive oil is used for cooking, dressings, marinades, and dipping. Extra virgin olive oil comes from the first pressing and retains the most antioxidants and flavor.
Safety
Oral olive oil is likely safe at doses of up to 2 tablespoons (28 grams) per day.
Frequently Asked Questions
References
Sources59 references
SupplementDEX uses only high-quality sources to determine supplement effectiveness.
SupplementDEX Database · Breast cancer
5 references1.SupplementDEX Database: Breast cancer — Olive oil intake and cancer risk: A systematic review and meta-analysis2022
A meta-analysis of 929,771 subjects found highest vs lowest olive oil consumption associated with 31% lower overall cancer likelihood, including breast and gastrointestinal cancers.
2.SupplementDEX Database: Breast cancer — Olive oil intake is inversely related to cancer prevalence: a systematic review and a meta-analysis of 13,800 patients and 23,340 controls in 19 observational studies2011
A meta-analysis of 19 observational studies (13,800 cancer patients) found highest vs lowest olive oil intake associated with lower odds of any cancer (OR 0.59) and breast cancer.
3.SupplementDEX Database: Breast cancer — Consumption of olive oil and specific food groups in relation to breast cancer risk in Greece1995
In 820 Greek breast cancer cases vs controls, olive oil consumption showed an inverse trend with breast cancer risk (OR 0.87 per 30 g/day increment, P = 0.03).
4.SupplementDEX Database: Breast cancer — Olive oil, other dietary fats, and the risk of breast cancer (Italy)1995
In 2564 Italian breast cancer cases vs 2588 controls, each 30 g/day increment in olive oil intake was associated with 11% lower breast cancer odds (OR 0.89, P = 0.03).
5.SupplementDEX Database: Breast cancer — Dietary fat, olive oil intake and breast cancer risk1994
In 762 Spanish breast cancer cases vs 988 controls, highest vs lowest olive oil intake quartile was associated with 34% lower breast cancer risk (OR 0.66) with a significant trend.
SupplementDEX Database · Cardiovascular disease
12 references6.SupplementDEX Database: Cardiovascular disease — Olive oil consumption is associated with a lower risk of cardiovascular disease and stroke2022
In three cohorts (AWHS, SUN, EPIC-Spain), olive oil intake ≥30 g/day was associated with lower CVD and stroke risk, strongest for virgin olive oil.
7.SupplementDEX Database: Cardiovascular disease — Consumption of Olive Oil and Risk of Total and Cause-Specific Mortality Among U.S. Adults2022
In 92,383 US adults followed 28 years, olive oil intake >7 g/day was associated with 19% lower all-cause mortality (HR 0.81) vs rarely consuming olive oil.
8.SupplementDEX Database: Cardiovascular disease — Effect of olive oil consumption on cardiovascular disease, cancer, type 2 diabetes, and all-cause mortality: A systematic review and meta-analysis2022
A meta-analysis of 806,203 participants found each olive oil increment associated with 16% lower cardiovascular disease risk and reduced all-cause mortality.
9.SupplementDEX Database: Cardiovascular disease — Olive Oil Consumption and Cardiovascular Risk in U.S. Adults2020
In 92,978 US adults followed 24 years, olive oil intake >7 g/day was associated with 14% lower CVD and 18% lower CHD risk vs nonconsumers.
10.SupplementDEX Database: Cardiovascular disease — The Mediterranean Diet and Cardiovascular Disease: Gaps in the Evidence and Research Challenges2019
A narrative review concluded cohort studies support Mediterranean diet benefits for CVD, but RCT evidence is limited to testing individual components such as olive oil or nuts.
11.SupplementDEX Database: Cardiovascular disease — Olive oil consumption and 10-year (2002-2012) cardiovascular disease incidence: the ATTICA study2019
In 2020 ATTICA participants followed ~8.4 years, exclusive olive oil use was associated with 93% lower 10-year cardiovascular disease incidence vs nonuse (RR 0.07).
12.SupplementDEX Database: Cardiovascular disease — Mediterranean-style diet for the primary and secondary prevention of cardiovascular disease2019
A Cochrane meta-analysis found Mediterranean-style diet interventions associated with reduced cardiovascular events in primary and secondary prevention populations vs minimal intervention.
13.SupplementDEX Database: Cardiovascular disease — Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts2018
A revised PREDIMED analysis of 7447 high-risk adults (ages 55–80) found a Mediterranean diet with extra-virgin olive oil or nuts reduced major cardiovascular events over 4.8 years versus a low-fat control (HR 0.69 and 0.72).
14.SupplementDEX Database: Cardiovascular disease — Olive oil intake and mortality within the Spanish population (EPIC-Spain)2012
In 40,622 Spanish EPIC participants followed 13.4 years, highest olive oil intake quartile had 26% lower all-cause mortality and 44% lower cardiovascular mortality vs nonconsumers.
15.SupplementDEX Database: Cardiovascular disease — Risk of first non-fatal myocardial infarction negatively associated with olive oil consumption: a case-control study in Spain2002
A Spanish case-control study of 171 first MI patients and matched controls found highest olive oil intake (median 54 g/day) associated with 82% lower first MI risk after adjustment (OR 0.18).
16.SupplementDEX Database: Cardiovascular disease — Consumption of olive oil, butter, and vegetable oils and coronary heart disease risk factors. The Research Group ATS-RF2 of the Italian National Research Council1990
A cross-sectional study of 4903 Italian adults (ages 20–59) found olive oil intake inversely associated with cholesterol, glucose, and systolic blood pressure, while butter linked to higher risk factors.
17.SupplementDEX Database: Cardiovascular disease — The diet and 15-year death rate in the seven countries study1986
In 11,579 men across 15 Seven Countries cohorts followed 15 years, higher monounsaturated fat (mainly oleic acid from olive oil) correlated with lower all-cause and coronary death rates.
SupplementDEX Database · Constipation
3 references18.SupplementDEX Database: Constipation — Evaluation of the Anti-constipation Effects of Abdominal Application of Olive Oil Ointment in Children 1-4 Years Old: A Pilot Placebo-Controlled, Double-Blind, Randomized Clinical Trial2021
A double-blind RCT in 40 children (ages 1–4) with functional constipation found abdominal olive oil ointment twice daily for 4 days improved stool frequency versus placebo with no adverse effects.
19.SupplementDEX Database: Constipation — The usefulness of olive oil enema in children with severe chronic constipation2021
A retrospective review of 118 children with severe chronic constipation found olive oil enemas (1–2 mL/kg) effective for fecal disimpaction in 77.6% and as a lubricant in 76.9%.
20.SupplementDEX Database: Constipation — Consensus statement AIGO/SICCR diagnosis and treatment of chronic constipation and obstructed defecation (part II: treatment)2012
An Italian consensus review found insufficient evidence that fluid or exercise changes relieve chronic constipation; fiber, osmotic laxatives, prucalopride, and lubiprostone had trial support.
SupplementDEX Database · Diabetes
2 references21.SupplementDEX Database: Diabetes — Effect of extra virgin olive oil consumption on glycemic control: A systematic review and meta-analysis2021
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.
22.SupplementDEX Database: Diabetes — Olive 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.
SupplementDEX Database · High blood pressure
1 reference23.SupplementDEX Database: High blood pressure — Olive oil and reduced need for antihypertensive medications2000
A crossover RCT in 23 hypertensive patients found 6 months on extra-virgin olive oil lowered blood pressure and cut antihypertensive drug needs 48% versus a sunflower oil diet.
SupplementDEX Database · Obesity
3 references24.SupplementDEX Database: Obesity — Olive oil and body fat: a systematic review with meta-analysis2023
A systematic review of 52 trials found olive oil did not clearly alter body fat distribution overall, though capsule supplementation showed a small waist-circumference increase in one analysis.
25.SupplementDEX Database: Obesity — The effect of ketogenic diet on serum lipid concentrations in children with medication resistant epilepsy2021
In 73 children with medication-resistant epilepsy on a ketogenic diet for up to 24 months, total cholesterol and triglycerides rose at 1 month but trended downward over time while BMI increased.
26.SupplementDEX Database: Obesity — Consumption of extra virgin olive oil improves body composition and blood pressure in women with excess body fat: a randomized, double-blinded, placebo-controlled clinical trial2018
A 9-week RCT in 41 women with excess body fat found 25 mL/day extra virgin olive oil on an energy-restricted diet doubled fat loss (~2.4 vs 1.3 kg) and lowered diastolic blood pressure versus soybean oil.
SupplementDEX Database · Otitis media
1 reference27.SupplementDEX Database: Otitis media — Efficacy of Auralgan for treating ear pain in children with acute otitis media1997
In 54 children (ages 5–19) with acute otitis media ear pain on acetaminophen, Auralgan ear drops provided modestly greater pain relief than olive oil placebo by 30 minutes.
SupplementDEX Database · Age-related fatigue
1 reference28.SupplementDEX Database: Age-related fatigue — Olive oil consumption is associated with lower frailty risk: a prospective cohort study of community-dwelling older adults2022
In 1896 community-dwelling older adults followed 3.5 years, highest tertile of total olive oil intake (30.8 g/day) was associated with 53% lower frailty incidence vs lowest tertile.
29.SupplementDEX Database: Cognitive performance — Olive Oil Intake Associated with Increased Attention Scores in Women Living with HIV: Findings from the Chicago Women's Interagency HIV Study2019
In 166 women (113 with HIV), higher olive oil use was associated with better attention, verbal learning, and memory scores, with attention gains seen only in women living with HIV.
SupplementDEX Database · Colorectal cancer
2 references30.SupplementDEX Database: Colorectal cancer — Olive oil, diet and colorectal cancer: an ecological study and a hypothesis2000
An ecological analysis of 28 countries found higher national olive oil intake inversely associated with colorectal cancer incidence alongside meat and fish intake patterns.
31.SupplementDEX Database: Colorectal cancer — Olive oil, other seasoning fats, and the risk of colorectal carcinoma1998
An Italian case-control study of 1953 colorectal cancer cases and 4154 controls found higher olive oil intake associated with modestly lower colorectal cancer risk (OR 0.83 highest vs lowest tertile).
SupplementDEX Database · Depression
1 reference32.SupplementDEX Database: Depression — Extra-Virgin Olive Oil Improves Depression Symptoms Without Affecting Salivary Cortisol and Brain-Derived Neurotrophic Factor in Patients With Major Depression: A Double-Blind Randomized Controlled Trial2022
An RCT of 73 adults with major depression found 25 mL/day extra-virgin olive oil for 52 days reduced depression scores versus sunflower oil, especially in severe depression, without changing cortisol or BDNF.
33.SupplementDEX Database: Diabetic foot ulcers — The effect of topical olive oil dressing on the healing of grade 1 and 2 diabetic foot ulcers: An assessor-blind randomized controlled trial in type 2 diabetes patients2022
An RCT of 60 type 2 diabetes patients with grade 1–2 foot ulcers found daily topical olive oil plus standard care for 4 weeks healed 76.6% completely versus none in standard care alone.
SupplementDEX Database · Dyslipidemia
6 references34.SupplementDEX Database: Dyslipidemia — Traditional Brazilian Diet and Olive Oil Reduce Cardiometabolic Risk Factors in Severely Obese Individuals: A Randomized Trial2020
A 12-week RCT in 149 severely obese adults found 52 mL/day extra virgin olive oil or a traditional Brazilian diet each modestly improved some cardiometabolic markers, with LDL/HDL ratio falling on olive oil.
35.SupplementDEX Database: Dyslipidemia — Comparison of blood lipid-lowering effects of olive oil and other plant oils: A systematic review and meta-analysis of 27 randomized placebo-controlled clinical trials2019
A meta-analysis of 27 RCTs in 1089 participants found olive oil raised HDL more but lowered total cholesterol, LDL, and triglycerides less than other plant oils.
36.SupplementDEX Database: Dyslipidemia — Effects of dietary extra virgin olive oil on serum lipid resistance to oxidation and fatty acid composition in elderly lipidemic patients2003
In 26 elderly dyslipidemic patients, 20 g/day extra virgin olive oil for 6 weeks lowered cholesterol, increased LDL oxidation lag time, and shifted serum fatty acids toward oleic acid.
37.SupplementDEX Database: Dyslipidemia — Beneficial nutritional properties of olive oil: implications for postprandial lipoproteins and factor VII2001
In Northern European men switched to an olive oil–rich diet, LDL cholesterol fell 15% and postprandial triglyceride and factor VII responses improved toward Mediterranean profiles.
38.SupplementDEX Database: Dyslipidemia — Effects of hypocaloric dietary treatment enriched in oleic acid on LDL and HDL subclass distribution in mildly obese women1999
In 20 mildly obese women, a 6-month hypocaloric olive oil–enriched diet improved dense LDL and HDL2 profiles more than a high-carbohydrate diet despite similar ~11% weight loss.
39.SupplementDEX Database: Dyslipidemia — Effects of long-term monounsaturated- vs polyunsaturated-enriched diets on lipoproteins in healthy men and women1992
In 78 healthy adults, switching from sunflower to olive oil for 16–28 weeks raised HDL cholesterol 17–30% and lowered the total cholesterol:HDL ratio in both sexes.
SupplementDEX Database · Eczema
2 references40.SupplementDEX Database: Eczema — Comparing the Therapeutic Effects of Aloe vera and Olive Oil Combination Cream versus Topical Betamethasone for Atopic Dermatitis: A Randomized Double-blind Clinical Trial2020
In a 6-week RCT of 36 atopic dermatitis patients, Olivederma (aloe plus olive oil) improved SCORAD and quality of life more than topical betamethasone, with eosinophil and IgE improvements.
41.SupplementDEX Database: Eczema — Topical application of natural honey, beeswax and olive oil mixture for atopic dermatitis or psoriasis: partially controlled, single-blinded study2003
In 39 patients with atopic dermatitis or psoriasis, a honey–beeswax–olive oil mixture improved symptoms in most cases and allowed corticosteroid dose reduction in several patients.
SupplementDEX Database · Helicobacter pylori
1 reference42.SupplementDEX Database: Helicobacter pylori — Assessment of Helicobacter pylori eradication by virgin olive oil2012
Two pilot trials in 60 H. pylori–infected adults found 30 g/day virgin olive oil for 14 days achieved only 10–40% eradication rates, with 13 subjects withdrawing due to taste or nausea.
SupplementDEX Database · Metabolic syndrome
1 reference43.SupplementDEX Database: Metabolic syndrome — Daily Use of Extra Virgin Olive Oil with High Oleocanthal Concentration Reduced Body Weight, Waist Circumference, Alanine Transaminase, Inflammatory Cytokines and Hepatic Steatosis in Subjects with the Metabolic Syndrome: A 2-Month Intervention Study2020
In 23 adults with metabolic syndrome and hepatic steatosis, 30 g/day high-oleocanthal olive oil for 2 months reduced weight, waist circumference, ALT, fatty liver index, and pro-inflammatory cytokines.
44.SupplementDEX Database: Mild cognitive impairment — Extra-Virgin Olive Oil Enhances the Blood-Brain Barrier Function in Mild Cognitive Impairment: A Randomized Controlled Trial2022
An RCT of 25 adults with mild cognitive impairment found 6 months of extra-virgin olive oil improved dementia ratings, reduced blood-brain barrier permeability, and enhanced brain connectivity versus refined olive oil.
45.SupplementDEX Database: Mild cognitive impairment — A Randomized Clinical Trial of Greek High Phenolic Early Harvest Extra Virgin Olive Oil in Mild Cognitive Impairment: The MICOIL Pilot Study2020
An RCT in mild cognitive impairment found 50 mL/day high- or moderate-phenolic olive oil for 12 months improved cognitive scores versus Mediterranean diet advice alone.
46.SupplementDEX Database: Nonalcoholic fatty liver disease (NAFLD) — Olive oil lessened fatty liver severity independent of cardiometabolic correction in patients with non-alcoholic fatty liver disease: A randomized clinical trial2019
A 12-week RCT in 66 NAFLD patients found 20 g/day olive oil reduced fatty liver grade more than sunflower oil on a hypocaloric diet, independent of most cardiometabolic changes.
SupplementDEX Database · Oral health
2 references47.SupplementDEX Database: Oral health — Randomized clinical trial on the clinical effects of a toothpaste containing extra virgin olive oil, xylitol, and betaine in gingivitis2023
A 4-month RCT in 61 adults with gingivitis found toothpaste with extra virgin olive oil, xylitol, and betaine reduced gingival bleeding and biofilm more than placebo or commercial toothpaste.
48.SupplementDEX Database: Oral health — Effect of subgingival application of topical ozonated olive oil in the treatment of chronic periodontitis: a randomized, controlled, double blind, clinical and microbiological study2012
A split-mouth RCT in 20 chronic periodontitis patients found subgingival ozonated olive oil as adjunct or monotherapy improved clinical and microbiological periodontal measures over 8 weeks.
SupplementDEX Database · Oral mucositis
1 reference49.SupplementDEX Database: Oral mucositis — The efficacy of honey or olive oil on the severity of oral mucositis and pain compared to placebo (standard care) in children with leukemia receiving intensive chemotherapy: A randomized controlled trial (RCT)2023
An RCT in 42 children with leukemia and chemotherapy-induced oral mucositis found Manuka honey reduced mucositis severity most; olive oil reduced pain versus standard care but less than honey.
SupplementDEX Database · Ovarian cancer
1 reference50.SupplementDEX Database: Ovarian cancer — Olive oil, seed oils and other added fats in relation to ovarian cancer (Italy)2002
An Italian case-control study of 1031 ovarian cancer cases and 2411 controls found highest olive oil intake associated with 32% lower ovarian cancer risk (OR 0.68) versus lowest intake.
51.SupplementDEX Database: Postoperative chylothorax — Preoperative Administration of Olive Oil Reduces Chylothorax After Minimally Invasive Esophagectomy2019
A propensity-matched study of 384 esophageal cancer patients found preoperative oral olive oil before minimally invasive esophagectomy reduced chylothorax incidence to 0% versus 3.1% in controls.
SupplementDEX Database · Postoperative pain
1 reference52.SupplementDEX Database: Postoperative pain — The effect of olive cream on pain and healing of caesarean section wounds: a randomised controlled clinical trial2022
An RCT in 103 women after caesarean section found topical olive cream twice daily for 8 days reduced pain and improved wound healing scores versus placebo or no treatment.
SupplementDEX Database · Pressure ulcers
3 references53.SupplementDEX Database: Pressure ulcers — Efficacy and Safety of Topical Application of Olive Oil for Preventing Pressure Ulcers: A Systematic Review and Meta-Analysis of Randomized Controlled Trials2022
A meta-analysis of 4 RCTs found topical olive oil reduced pressure ulcer incidence (RR 0.56) versus other treatments with no increase in adverse effects.
54.SupplementDEX Database: Pressure ulcers — Effect of Olive Oil in Preventing the Development of Pressure Ulcer Grade One in Intensive Care Unit Patients2020
A clinical trial in 72 ICU patients found topical olive oil plus standard skin care lowered pressure ulcer severity scores on days 4 and 7 versus standard care alone.
55.SupplementDEX Database: Pressure ulcers — The Effect of Using Olive Oil and Fish Oil Prophylactic Dressings on Heel Pressure Injury Development in Critically Ill Patients2020
A 7-day trial in 50 critically ill patients at pressure injury risk found neither olive oil nor fish oil heel dressings prevented heel pressure injuries, with no difference between oils.
56.SupplementDEX Database: Radiation dermatitis — Natural and miscellaneous agents for the prevention of acute radiation dermatitis: a systematic review and meta-analysis2023
Meta-analysis of 19 prevention trials found oral enzymes and olive oil reduced grade 2+ radiation dermatitis; aloe vera showed no significant preventive effect.
57.SupplementDEX Database: Stretch marks (Striae gravidarum) — The effect of olive oil on prevention of striae gravidarum: a randomized controlled clinical trial2012
An RCT in 100 nulliparous pregnant women found twice-daily topical olive oil did not significantly reduce striae gravidarum overall, though severe striae were less frequent in the olive oil group.
58.SupplementDEX Database: Stretch marks (Striae gravidarum) — Effects of olive oil on striae gravidarum in the second trimester of pregnancy2011
An RCT during the second trimester found olive oil applied twice daily did not reduce striae gravidarum versus no treatment (40% vs 50% occurrence).
SupplementDEX Database · Tinea
1 reference59.SupplementDEX Database: Tinea — An alternative treatment for pityriasis versicolor, tinea cruris, tinea corporis and tinea faciei with topical application of honey, olive oil and beeswax mixture: an open pilot study2004
In 37 patients with fungal skin infections, a honey–olive oil–beeswax mixture applied three times daily for up to 4 weeks improved symptoms in 75–86% and achieved mycological cure in 62–75%.