Olive Leaf Extract
Herb ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Rich in oleuropein with antimicrobial, antioxidant, and cardiovascular benefits.
Exploratory record, not a reviewed medical publication.
See the editorial and medical-review policies for the publication gate.
This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.
What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
Olive Leaf Extract is a herb most often used for immune support, blood pressure, antioxidant. NutriStack rates the overall evidence as emerging. A typical adult dose is 500-1,000 mg daily (standardized to 18-20% oleuropein), commonly taken as standardized extract. This profile indexes 19 sources.
The bottom line
Evidence rating emerging. Most-documented uses: immune support, blood pressure, antioxidant. 19 sources indexed (2010–2026), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Oleuropein and hydroxytyrosol inhibit bacterial, viral, and fungal growth. Modulate eNOS for blood pressure support. Potent antioxidant via radical scavenging and metal chelation.17,3
Dosing & protocol.
What it actually costs.
Real-world pricing across three quality tiers. Assumes Oleuropein-Standardized Olive Leaf.
Assumes 500-1,000 mg/day. Vendor basis: NOW/iHerb, Vitacost, Life Extension, and Amazon marketplace; 18-20% oleuropein extracts set the mid tier. Updated 2026-05-28.
The same dose, as food.
How much you'd eat to match a supplemental dose.
Leaf extract is much more concentrated in oleuropein than common olive foods.
Full safety detail.
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Meta-analyses & systematic reviews
5- 1Olive leaf extract effect on cardiometabolic risk factors: a systematic review and meta-analysis of randomized clinical trialsPMIDAlvares AA, Garcez A, Silva LT, Averbuch N, Garavaglia J · Nutr Rev · 2024
Systematic review and meta-analysis of 12 RCTs (703 patients) found OLE showed positive correlations with glucose metabolism (4 RCTs), blood pressure (2 RCTs), lipid profile (2 RCTs), and inflammatory markers (2 RCTs).
- 2The effects of olive leaf extract on cardiovascular risk factors in the general adult population: a systematic review and meta-analysis of randomized controlled trialsPMCMarx W et al. · Nutrition Reviews · 2022
Reductions in total cholesterol, LDL cholesterol, triglycerides, and interleukin-8 observed with olive leaf extract compared to control.
- 3Oral administration of oleuropein and olive leaf extract has cardioprotective effects in rodents: A systematic reviewPMIDMenezes RCR, Peres KK, Costa-Valle MT et al. · Revista portuguesa de cardiologia : orgao oficial da Sociedade Portuguesa de Cardiologia = Portuguese journal of cardiology : an official journal of the Portuguese Society of Cardiology · 2022
Menezes RCR, Peres KK, Costa-Valle MT et al.. Oral administration of oleuropein and olive leaf extract has cardioprotective effects in rodents: A systematic review. Revista portuguesa de cardiologia : orgao oficial da Sociedade Portuguesa de Cardiologia = Portuguese journal of cardiology : an official journal of the Portuguese Society of Cardiology. 2022
- 4Olive leaf extract effect on cardiometabolic profile among adults with prehypertension and hypertension: a systematic review and meta-analysisPMIDIsmail MA et al. · European Journal of Integrative Medicine · 2021
Five trials (325 patients) showed olive leaf extract decreased 24-hour BP, BP load, and diastolic BP variability with improvements in lipid profile and inflammation.
- 5Oleuropein and olive leaf extract as hypotensive: a systematic review and meta-analysisSource linkedPMIDLockyer S, Rowland I, Spencer JPE et al. · Eur J Nutr · 2017
Randomized controlled trials
10- 6Effects of a combination of olive leaf extract and potassium on blood pressure in participants with mild to moderate hypertension: A double blind, randomized, placebo-controlled trialPMIDFladerer-Grollitsch JP, Bucar F, Klein T et al. · Phytomedicine : international journal of phytotherapy and phytopharmacology · 2026
Fladerer-Grollitsch JP, Bucar F, Klein T et al.. Effects of a combination of olive leaf extract and potassium on blood pressure in participants with mild to moderate hypertension: A double blind, randomized, placebo-controlled trial. Phytomedicine : international journal of phytotherapy and phytopharmacology. 2026
- 7Adjuvant treatment with an oleuropein-enriched olive leaf extract improves periodontal outcomes in older adults with periodontitis: Metabolomic insights from a randomized controlled trialPMIDForbes-Hernández TY, Vargas-Corral FG, Bullón B et al. · Phytomedicine : international journal of phytotherapy and phytopharmacology · 2026
Forbes-Hernández TY, Vargas-Corral FG, Bullón B et al.. Adjuvant treatment with an oleuropein-enriched olive leaf extract improves periodontal outcomes in older adults with periodontitis: Metabolomic insights from a randomized controlled trial. Phytomedicine : international journal of phytotherapy and phytopharmacology. 2026
- 8Phenolic-rich extract of olive leaf with a hypocaloric diet alleviates oxidative stress in obese females: a randomized double-blind placebo controlled trialPMIDHaidari F, Mohammad-Shahi M, Jalali MT, Ahmadi-Angali K, Shayesteh F · Nutr Metab Cardiovasc Dis · 2025
RCT of 70 obese women found OLE (250 mg/day) combined with a hypocaloric diet for 8 weeks significantly reduced serum malondialdehyde compared to placebo + hypocaloric diet.
- 9Impact of olive leaf extract on pain management and functional improvement in elderly patients with knee osteoarthritis: A randomized controlled trialPMIDRoshani M, Delfan B, Yarahmadi S, Saki M, Birjandi M · Explore (NY) · 2025
RCT of 100 elderly patients with knee osteoarthritis found OLE (oral and/or topical) significantly reduced pain scores and improved daily functioning. Combination of oral and topical showed the most pronounced effects.
- 10Effects of olive leaf extract supplementation on systemic markers of tissue aging and remodeling in postmenopausal women: a randomized controlled trial with exploratory skin outcomesPMIDLasfar A, van Stratum SLM, Imperatrice M et al. · Frontiers in nutrition · 2025
Lasfar A, van Stratum SLM, Imperatrice M et al.. Effects of olive leaf extract supplementation on systemic markers of tissue aging and remodeling in postmenopausal women: a randomized controlled trial with exploratory skin outcomes. Frontiers in nutrition. 2025
- 11Evaluating the effectiveness of topical olive leaf extract emulgel in managing recurrent herpes labialis: a randomized controlled clinical studyPMIDGaizeh Al-Hallak MA, Hsaian JA, Aljoujou AA · Scientific reports · 2024
Gaizeh Al-Hallak MA, Hsaian JA, Aljoujou AA. Evaluating the effectiveness of topical olive leaf extract emulgel in managing recurrent herpes labialis: a randomized controlled clinical study. Scientific reports. 2024
- 12The effect of olive leaf extract on cardiovascular health markers: a randomized placebo-controlled clinical trialPMIDBoss A et al. · European Journal of Nutrition · 2021
Olive leaf extract supplementation demonstrated effects on cardiovascular health markers in a placebo-controlled trial.
- 13The Effect of Olive Leaf Extract on Upper Respiratory Illness in High School Athletes: A Randomised Control TrialPMIDSomerville V et al. · Nutrients · 2019
Olive leaf extract supplementation produced a significant 28% reduction in sick days in high school athletes, though illness incidence was not significantly different.
- 14Impact of phenolic-rich olive leaf extract on blood pressure, plasma lipids and inflammatory markers: a randomised controlled trialPMIDLockyer S et al. · European Journal of Nutrition · 2017
In pre-hypertensive males, 136 mg oleuropein daily significantly lowered daytime and 24-hour systolic and diastolic blood pressure.
- 15Effect of olive leaf extract on blood pressure in borderline hypertensive patients: a randomized, controlled trialSource linkedPMIDSusalit E, Agus N, Effendi I et al. · Phytomedicine · 2011
Reviews & position papers
1- 16Oleuropein in olive and its pharmacological effectsSource linkedPMIDOmar SH · Sci Pharm · 2010
Mechanistic & preclinical
1- 17Assessment of the Antimicrobial Activity of Olive Leaf Extract Against Foodborne Bacterial PathogensPMCLiu Y et al. · Frontiers in Microbiology · 2017
At 62.5 mg/ml concentration, olive leaf extract almost completely inhibited growth of Listeria monocytogenes, E. coli O157:H7, and Salmonella Enteritidis.
Reference material
2- 18Lamti F, Trabelsi I, Dhaoui R et al.. Efficacy of olive leaf extracts in controlling blood pressure in hypertensive patients: a double-blind randomized clinical trial. Journal of hypertension. 2025Source linkedPMID
- 19Imperatrice M, Lasfar A, van Kalkeren CAJ et al.. Olive Leaf Extract Supplementation Improves Postmenopausal Symptoms: A Randomized, Double-Blind, Placebo-Controlled Parallel Study on Postmenopausal Women. Nutrients. 2024Source linkedPMID
Common questions.
Quick answers about Olive Leaf Extract, drawn from the data on this page.
What is Olive Leaf Extract?
Rich in oleuropein with antimicrobial, antioxidant, and cardiovascular benefits.
What is Olive Leaf Extract used for?
Commonly cited benefits of Olive Leaf Extract include: Immune support; Blood pressure; Antioxidant; Antimicrobial. NutriStack rates the overall evidence as emerging.
What is a typical dose of Olive Leaf Extract?
A typical adult dose of Olive Leaf Extract is 500-1,000 mg daily (standardized to 18-20% oleuropein). The commonly recommended form is Standardized extract. These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of Olive Leaf Extract?
Reported side effects include gi upset, headache (herxheimer reaction), dizziness. This is educational information; check with a healthcare professional before use.
How strong is the evidence for Olive Leaf Extract?
NutriStack rates this as Emerging, meaning early RCT signal, mechanistic data, or limited human evidence. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
Olive Leaf Extract in NutriStack.
Add it to your stack, see how it interacts with everything else you take, and get a Stack Score that updates the moment it does.