Supplement
Olive leaf extract is a concentrate made from olive tree leaves, rich in plant compounds such as oleuropein that act as antioxidants in the body. The best-supported finding is for blood pressure, where studies found readings came down in people with high or borderline-high levels, and the evidence is moderate. That rests on just two studies with 188 people, and blood sugar results came from small studies with limited evidence.
Sources: PMID 18729245; PMID 38287654
- Updated
- How we grade
- 5 studies cited
- Best evidence
- Grade B
- Conditions studied
- 5
- Outcomes
- 28
- Graded outcomes
- 0140
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Blood Pressure Moderate Improvement | Improves (the measure goes down) | Moderate effect | 2 studies | 188 people | ||
| High-density lipoprotein (HDL) Small Improvement | Improves (the measure goes up) | Small effect | 148 people | |||
| Liver Enzymes | Changes; see studies | 1 study | 148 people | |||
Studies that measured liver enzymes | ||||||
| Total cholesterol | Improves (the measure goes down) | 1 study | 148 people | |||
Studies that measured total cholesterol | ||||||
| Low-density lipoprotein (LDL) | Improves (the measure goes down) | 148 people | ||||
| Triglycerides | Improves (the measure goes down) | 148 people | ||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| HbA1c Small Improvement | Improves (the measure goes down) | Small effect | 1 study | 79 people | ||
Studies that measured hba1c | ||||||
| Insulin | Changes; see studies | 79 people | ||||
General Cardiovascular Health
- Blood glucose: improves
- Blood Pressure: improves
- Total cholesterol: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Blood glucose Small Improvement | Improves (the measure goes down) | Small effect | 214 people | |||
| Blood Pressure | Improves (the measure goes down) | 2 studies | 2,625 people | |||
| Total cholesterol | Improves (the measure goes down) | 1 study | 272 people | |||
Studies that measured total cholesterol | ||||||
| High-density lipoprotein (HDL) | Improves (the measure goes up) | 272 people | ||||
| Low-density lipoprotein (LDL) | Improves (the measure goes down) | 272 people | ||||
| Triglycerides | Improves (the measure goes down) | 200 people | ||||
Metabolic Syndrome
- Blood glucose: improves
- Blood Pressure: improves
- Liver Enzymes: changes; see studies
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Blood glucose Small Improvement | Improves (the measure goes down) | Small effect | 45 people | |||
| Blood Pressure | Improves (the measure goes down) | 2 studies | 45 people | |||
| Liver Enzymes | Changes; see studies | 1 study | 45 people | |||
Studies that measured liver enzymes | ||||||
| Total cholesterol | Improves (the measure goes down) | 1 study | 45 people | |||
Studies that measured total cholesterol | ||||||
| Glycemic Control | Improves (the measure goes up) | 45 people | ||||
| High-density lipoprotein (HDL) | Improves (the measure goes up) | 45 people | ||||
| IGF Binding Protein | Improves (the measure goes up) | 45 people | ||||
| IGF-1 | Improves (the measure goes up) | 45 people | ||||
| Inflammation | Improves (the measure goes down) | 45 people | ||||
| Insulin | Changes; see studies | 45 people | ||||
| LDL Oxidation | Improves (the measure goes down) | 45 people | ||||
| Low-density lipoprotein (LDL) | Improves (the measure goes down) | 45 people | ||||
| Triglycerides | Improves (the measure goes down) | 45 people | ||||
High Cholesterol
- Blood Pressure: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Blood Pressure | Improves (the measure goes down) | 2 studies | 40 people | |||
Key findings
- Blood PressureImproves (the measure goes down)
- HbA1cImproves (the measure goes down)
- High-density lipoprotein (HDL)Improves (the measure goes up)
Shop the evidence-backed picks
Third-party tested Olive Leaf Extract products, in the forms the graded studies used where we can match them.
- Grade B
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Studies cited
5 studies from PubMed
- Olive (Olea europaea) leaf extract effective in patients with stage-1 hypertension: comparison with Captopril
- Food supplementation with an olive (Olea europaea L.) leaf extract reduces blood pressure in borderline hypertensive monozygotic twins
- Olive (Olea europaea L.) Leaf Polyphenols Improve Insulin Sensitivity in Middle-Aged Overweight Men: A Randomized, Placebo-Controlled, Crossover Trial
- Olive leaf extract as a hypoglycemic agent in both human diabetic subjects and in rats
- Olive leaf extract effect on cardiometabolic risk factors: a systematic review and meta-analysis of randomized clinical trials.