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Olive Leaf Extract
Olive leaf extract is a reasonable pick if your goal is mild blood pressure reduction or modest lipid improvements, but most of the other claims around it are oversold.
- Evidence
- Mixed Evidence
- Category
- Immune Support
- Best form
- Standardized leaf extract (16-25% oleuropein)
- Effective dose
- 500-1000mg daily of an extract standardized to 16-25% oleuropein, often split as 500mg twice daily
- Lab tested
- 3 of 9 products
- Category
- Immune Support
- Best form
- Standardized leaf extract (16-25% oleuropein)
- Effective dose
- 500-1000mg daily of an extract standardized to 16-25% oleuropein, often split as 500mg twice daily
- Lab tested
- 3 of 9 products
Key takeaways
- →Solid for mild blood pressure reduction at 500-1000mg/day of a standardized extract; effect size around 4-12 mmHg systolic.
- →Use a product standardized to 16-25% oleuropein. Generic leaf powder has no clinical track record.
- →Triglyceride and LDL effects are real but modest. Insulin sensitivity data is promising but limited.
- →Antiviral and cold-and-flu marketing is not backed by human trials in healthy people. Treat those claims as unproven.
What Is Olive Leaf Extract?
Olive leaf extract is a reasonable pick if your goal is mild blood pressure reduction or modest lipid improvements, but most of the other claims around it are oversold. The strongest data is for systolic blood pressure: an 8-week trial of 232 people with stage-1 hypertension found 500mg of EFLA943 twice daily lowered systolic BP by about 11.5 mmHg, statistically similar to captopril 12.5-25mg twice daily, with a side benefit of triglyceride reduction the captopril group did not see. A 2022 meta-analysis of 12 RCTs (819 participants) confirmed roughly 3.86 mmHg systolic reduction across the broader population and a meaningful drop in triglycerides.
The lipid story is consistent but small. Trials show modest reductions in triglycerides and LDL cholesterol, mostly in people with elevated baseline values. Do not expect statin-level effects.
Insulin sensitivity has one well-designed crossover trial (de Bock 2013) showing a 15% improvement and a 28% bump in pancreatic beta-cell function in middle-aged overweight men over 12 weeks. That is interesting but it is one trial in a narrow population, so put it in the "early signal" bucket, not "established."
The antiviral and immune marketing is where the gap is biggest. Oleuropein has clear antiviral activity in test tubes against several viruses, but human trials are sparse, mostly small, and inconsistent. There is one randomized trial in hospitalized COVID-19 patients suggesting reduced length of stay, but it is a single small study in a sick inpatient population and does not justify "boost your immune system" claims for healthy people. Treat antiviral and cold-and-flu marketing as unproven.
Use a product standardized to oleuropein percentage. Generic "olive leaf powder" is not the same product, has no clinical data, and the active dose is anyone's guess.
Does It Work? The Evidence
How A-F grades workBlood pressure reduction (stage-1 hypertension)
Susalit et al. 2011 RCT (n=232): EFLA943 500mg twice daily reduced systolic BP by 11.5 mmHg, comparable to captopril; Razmpoosh et al. 2022 meta-analysis of 12 RCTs (819 participants): 3.86 mmHg systolic reduction; Ismail et al. 2021 meta-analysis: 5.78 mmHg systolic reduction at 500mg/day
Triglyceride and LDL cholesterol reduction
Razmpoosh et al. 2022 meta-analysis: triglycerides decreased by 9.51 mg/dL; Susalit et al. 2011: significant triglyceride reduction in olive leaf group only; Perrinjaquet-Moccetti et al. 2008 twin trial: cholesterol reductions across all dose groups
Insulin sensitivity and glucose control
de Bock et al. 2013 crossover RCT (n=46 overweight men): 15% improvement in insulin sensitivity, 28% improvement in beta-cell function; Wainstein et al. 2012: 500mg/day lowered HbA1c and fasting insulin in type 2 diabetics over 14 weeks
Antiviral and immune system support
In vitro and animal data show antiviral activity of oleuropein and hydroxytyrosol; one RCT in hospitalized COVID-19 patients (2022) suggested reduced length of stay, but human trials in healthy populations are missing
Antioxidant and inflammatory marker improvement
Ismail et al. 2021 meta-analysis: reductions in IL-6, IL-8, and TNF-alpha at 500mg/day; effects modest and limited by small sample sizes
| Grade | Claimed Benefit | Key Studies | Our Verdict |
|---|---|---|---|
| B | Blood pressure reduction (stage-1 hypertension) | Susalit et al. 2011 RCT (n=232): EFLA943 500mg twice daily reduced systolic BP by 11.5 mmHg, comparable to captopril; Razmpoosh et al. 2022 meta-analysis of 12 RCTs (819 participants): 3.86 mmHg systolic reduction; Ismail et al. 2021 meta-analysis: 5.78 mmHg systolic reduction at 500mg/day | Supported |
| B | Triglyceride and LDL cholesterol reduction | Razmpoosh et al. 2022 meta-analysis: triglycerides decreased by 9.51 mg/dL; Susalit et al. 2011: significant triglyceride reduction in olive leaf group only; Perrinjaquet-Moccetti et al. 2008 twin trial: cholesterol reductions across all dose groups | Early Signal |
| C | Insulin sensitivity and glucose control | de Bock et al. 2013 crossover RCT (n=46 overweight men): 15% improvement in insulin sensitivity, 28% improvement in beta-cell function; Wainstein et al. 2012: 500mg/day lowered HbA1c and fasting insulin in type 2 diabetics over 14 weeks | Early Signal |
| D | Antiviral and immune system support | In vitro and animal data show antiviral activity of oleuropein and hydroxytyrosol; one RCT in hospitalized COVID-19 patients (2022) suggested reduced length of stay, but human trials in healthy populations are missing | Not There Yet |
| C | Antioxidant and inflammatory marker improvement | Ismail et al. 2021 meta-analysis: reductions in IL-6, IL-8, and TNF-alpha at 500mg/day; effects modest and limited by small sample sizes | Early Signal |
How to Choose: Forms, Doses & What Matters
Clinical dose: 500-1000mg daily of an extract standardized to 16-25% oleuropein, often split as 500mg twice daily
Best forms: Standardized leaf extract (16-25% oleuropein), EFLA943 (the branded extract used in the Susalit hypertension trial), Liquid extracts standardized by oleuropein content per serving
Take 500mg twice daily with food, matching the dosing used in the Susalit hypertension trial. Single daily doses of 500-1000mg are also used in trials and are reasonable for general support. Take with meals to reduce the small chance of GI upset. Allow 6-8 weeks to see meaningful blood pressure changes, the trial endpoints were measured at 8 weeks. If you take BP medication, check your blood pressure regularly during the first month and tell your doctor.
Who Should Take Olive Leaf Extract?
Adults with stage-1 hypertension or pre-hypertension looking for a mild, well-tolerated adjunct (not a replacement for prescribed BP medication if you have stage-2 or higher). People with elevated triglycerides or borderline LDL who want a low-risk add-on. Adults with mildly impaired insulin sensitivity, especially overweight middle-aged men where the data is strongest. Anyone seeking general antioxidant support from a Mediterranean-diet-aligned supplement.
Who Should Avoid It?
Not for everyone
Side Effects & Safety
Product Scores
9 products scored on dosing accuracy, third-party testing, cost per effective dose, and label transparency.
The Scorecard: 9 Products Compared
Olive Leaf Extract 500mg (20% Oleuropein)
Designs for Health
$30.49 ÷ 60 days at ~753mg/day (1.5 servings × 500mg)
Designs for Health sells primarily through licensed practitioners, which adds an accountability layer most consumer brands skip
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Olive Leaf Premium Extract (20% Oleuropein)
Nature's Way
$13.49 ÷ 20 days at 750mg/day (3 servings × 250mg)
Nature's Way is one of the few mass-market brands that prints oleuropein milligrams per capsule on the front label
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Olive Leaf Extract 500mg
Pure Encapsulations$58.40 ÷ 80 days at ~750mg/day (1.5 servings × 500mg)
Pure Encapsulations is the standard pick for people with allergies or sensitivities, given its strict free-from formulation
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Olive Leaf Extract Super Strength 750mg (20% Oleuropein)
Swanson
$11.99 ÷ 60 days at 750mg/day (1 serving × 750mg)
If you want one capsule per day at the upper end of the clinical dose, this is the cheapest credible way to get there
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Olive Leaf Extract 250mg (22% Oleuropein) with Lemon Balm
Solaray
$16.49 ÷ 40 days at 750mg/day (3 servings × 250mg)
Reasonable choice if you also want lemon balm, but if you want isolated olive leaf to match the clinical literature, pick a single-ingredient product
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Olive Leaf Extract 500mg (6% Oleuropein)
NOW Foods$21.99 ÷ 81 days at ~737mg/day (1.5 servings × 500mg)
Affordable but the low oleuropein percentage means each 500mg capsule delivers only 30mg of the active compound
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Olive Leaf Liquid Phyto-Caps
Gaia Herbs$20.79 ÷ 28 days at 700mg/day (1 serving × 700mg)
Best fit for people who prefer whole-plant herbal preparations over isolated standardized extracts, but harder to dose-match to clinical-trial protocols
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Olive Leaf Complex Liquid (Natural Flavor)
Barlean's
$19.99 ÷ 21 days at ~752mg/day (0.8 servings × 1000mg)
If you prefer a liquid and want a high oleuropein dose per serving, Barlean's is the clearest pick
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Certified Organic Olive Leaf Liquid Extract (1 oz)
Herb Pharm
$11.99 ÷ 28 days at 700mg/day (1 serving × 700mg)
Best as a tincture-format option for traditional herbalism use, less useful for matching the standardized-extract clinical literature
Prices checked 2026-04-26. Cost shown is per clinically effective daily dose, not per pill.
Full Comparison
| Category | Olive Leaf Extract 500mg (20% Oleuropein) Designs for Health | Olive Leaf Premium Extract (20% Oleuropein) Nature's Way | Olive Leaf Extract 500mg Pure Encapsulations | Olive Leaf Extract Super Strength 750mg (20% Oleuropein) Swanson | Olive Leaf Extract 250mg (22% Oleuropein) with Lemon Balm Solaray | Olive Leaf Extract 500mg (6% Oleuropein) NOW Foods | Olive Leaf Liquid Phyto-Caps Gaia Herbs | Olive Leaf Complex Liquid (Natural Flavor) Barlean's | Certified Organic Olive Leaf Liquid Extract (1 oz) Herb Pharm |
|---|---|---|---|---|---|---|---|---|---|
| Brand Score | 88/100Winner | 86/100 | 85/100 | 84/100 | 79/100 | 78/100 | 76/100 | 73/100 | 72/100 |
| Dosing & Form | 22/25 | 22/25 | 22/25 | 25/25Winner | 18/25 | 16/25 | 18/25 | 22/25 | 14/25 |
| Purity | 22/25Winner | 19/25 | 22/25 | 16/25 | 19/25 | 19/25 | 19/25 | 16/25 | 19/25 |
| Value | 21/25 | 22/25Winner | 18/25 | 22/25 | 21/25 | 22/25 | 16/25 | 14/25 | 18/25 |
| Transparency | 23/25Winner | 23/25 | 23/25 | 21/25 | 21/25 | 21/25 | 23/25 | 21/25 | 21/25 |
| Cost/Day | $0.51 | $0.67 | $0.73 | $0.20Winner | $0.41 | $0.27 | $0.74 | $0.94 | $0.43 |
| Dose/Serving | 500mg | 250mg | 500mg | 750mg | 250mg | 500mg | 700mg | 1000mg | 700mg |
| Form | Olive Leaf Extract (20% oleuropein, 100mg per capsule) | Olive Leaf Extract (20% oleuropein, 50mg per capsule) | Olive Leaf Extract (min 15% oleuropein, typical 17-23%) | Olive Leaf Extract (20% oleuropein, 150mg per capsule) | Olive Leaf Extract (22% oleuropein) + Lemon Balm | Olive Leaf Extract (standardized to 6% oleuropein, 30mg per capsule) | Olive Leaf Extract (liquid phyto-cap, traditional whole-plant) | Fresh-pressed liquid (40% oleuropein, 95mg per tablespoon) | Liquid Extract (organic alcohol-based tincture) |
| Third-Party Tested | ✓ Yes | No | ✓ Yes | No | No | No | ✓ Yes | No | No |
| Proprietary Blend | No | No | No | No | No | No | No | No | No |
Frequently Asked Questions
What is the difference between EFLA943 and a generic olive leaf extract?
EFLA943 is the specific branded extract used in the Susalit 2011 hypertension trial that compared olive leaf to captopril. It is standardized to a defined oleuropein content and was the form that produced the 11.5 mmHg systolic blood pressure reduction. A generic extract standardized to a similar oleuropein percentage (16-25%) is a reasonable substitute, but it has not been directly tested head-to-head. Pure leaf powder with no oleuropein standardization is not equivalent and has no clinical evidence behind it.
Is olive oil the same as olive leaf extract?
No. Olive oil comes from the fruit and is rich in oleic acid and small amounts of polyphenols like hydroxytyrosol and oleocanthal. Olive leaf extract comes from the leaves and is concentrated in oleuropein, a different polyphenol that is the main active compound studied for blood pressure. Both are part of the Mediterranean diet picture, but they are not interchangeable, and the clinical trials on blood pressure used leaf extract specifically.
Does olive leaf extract really fight viruses?
In test tubes, oleuropein and hydroxytyrosol show antiviral activity against several viruses including influenza and herpes simplex. In humans, the evidence is much weaker. There is one randomized trial in hospitalized COVID-19 patients suggesting shorter hospital stays, but trials in healthy people preventing or treating common colds are missing. Marketing claims about immune boosting are running ahead of the evidence.
Can I take olive leaf extract with my blood pressure medication?
Talk to your doctor first. Olive leaf extract has measurable blood pressure lowering effects, and combining it with prescription antihypertensives (ACE inhibitors, ARBs, calcium channel blockers, diuretics) can cause hypotension, which feels like dizziness, lightheadedness, or fainting. If your doctor okays it, monitor your BP at home for the first 4-6 weeks and report any drops below your usual range.
How long until I see blood pressure changes?
The Susalit trial measured outcomes at 8 weeks. Most participants saw the bulk of the change by 6-8 weeks of consistent daily use. Do not expect overnight effects. If you have not seen any change after 12 weeks of dosing at 500mg twice daily with a properly standardized extract, it probably is not going to work for you.
What oleuropein percentage should I look for on the label?
Aim for 16-25% oleuropein, which is the clinical-grade range. Some products advertise higher percentages (40% or 50%), which can be legitimate if the manufacturer publishes a certificate of analysis, but very high concentrations also have not been studied directly in the major BP trials. If the label does not state an oleuropein percentage at all, treat it as unstandardized and skip it.
Does olive leaf extract help with weight loss?
Not directly. Some animal studies show favorable effects on metabolism and fat storage via insulin sensitivity improvements, but human trials have not shown meaningful weight loss from olive leaf extract alone. If you are looking for weight management, this is not the supplement to lead with.
Sources
- Susalit E, et al. Olive (Olea europaea) leaf extract effective in patients with stage-1 hypertension: comparison with Captopril. Phytomedicine. 2011;18(4):251-8.
- Razmpoosh E, et al. The effects of olive leaf extract on cardiovascular risk factors in the general adult population: a systematic review and meta-analysis of randomized controlled trials. Diabetol Metab Syndr. 2022;14(1):151.
- Ismail MA, et al. Olive leaf extract effect on cardiometabolic profile among adults with prehypertension and hypertension: a systematic review and meta-analysis. PeerJ. 2021;9:e11173.
- Perrinjaquet-Moccetti T, et al. Food supplementation with an olive (Olea europaea L.) leaf extract reduces blood pressure in borderline hypertensive monozygotic twins. Phytother Res. 2008;22(9):1239-42.
- de Bock M, et al. Olive (Olea europaea L.) leaf polyphenols improve insulin sensitivity in middle-aged overweight men: a randomized, placebo-controlled, crossover trial. PLoS One. 2013;8(3):e57622.
- Wainstein J, et al. Olive leaf extract as a hypoglycemic agent in both human diabetic subjects and in rats. J Med Food. 2012;15(7):605-10.
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. The products discussed on this page are not intended to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare professional before starting any supplement regimen.