Olive Leaf Extract: Uses, Benefits, Dosage & Safety

Last updated: June 2026 · Reviewed by the FactoWiki Editorial Team for clarity and source accuracy

What is Olive Leaf Extract?

Olive leaf extract comes from the leaves of the olive tree (Olea europaea), a staple of the Mediterranean tradition. Its main active compound is oleuropein, a polyphenol antioxidant also responsible for the bitter taste of olives. It is marketed for blood pressure, immune support, blood sugar and general 'cardiovascular wellness', usually as capsules or liquid standardised to oleuropein content.

What Olive Leaf Extract is commonly used for

In supplements, Olive Leaf Extract is most often included for brain & memory support support. It is used as nutritional support, not as a treatment for any medical condition — the distinction matters, because the claims on a sales page are often stronger than the evidence allows.

How Olive Leaf Extract works

Oleuropein and related polyphenols are antioxidants that may support blood-vessel function and have mild effects on blood pressure and the way the body handles glucose and fats. These mechanisms are plausible and fit the broader evidence that a Mediterranean-style diet supports heart health, but isolating olive leaf extract as a supplement is a different question from the overall dietary pattern.

What the evidence says

Here's an honest snapshot of what published research suggests about Olive Leaf Extract — including where the evidence is limited.

• Small randomised trials suggest olive leaf extract may modestly lower blood pressure, with some studies also reporting effects on blood sugar and cholesterol. (PubMed research)
• Overall the human evidence is limited and preliminary, with small studies and varied preparations, so conclusions remain tentative. (PubMed research)

Typical dosage used in studies

Trials have used varied doses, often in the range of 500-1,000 mg/day of extract standardised to oleuropein, over several weeks. Because the evidence is preliminary, no dose is firmly established. This is research information, not a recommendation.

Side effects and safety

Olive leaf extract is generally well tolerated; mild stomach upset, headache or dizziness are occasionally reported. Its main theoretical cautions follow from possible blood-pressure and blood-sugar lowering.

Medication interactions and who should avoid Olive Leaf Extract

Sources & further reading

The evidence summary above is drawn from these sources. For general, authoritative background you can also consult:

• PubMed research
• PubMed research
• NIH Office of Dietary Supplements
• NIH National Center for Complementary and Integrative Health
• MedlinePlus (U.S. National Library of Medicine)

Frequently asked questions

Does olive leaf extract lower blood pressure?

Small studies suggest a modest effect, but the evidence is preliminary. It is not a substitute for blood-pressure medication or a proven treatment.

Is it the same as olive oil?

No. Olive leaf extract comes from the leaves and is concentrated in oleuropein; olive oil comes from the fruit. Both feature in the Mediterranean tradition but are different products.

What dose is used in studies?

Often around 500-1,000 mg/day of a standardised extract, but doses and preparations vary and no standard is firmly established.

Is olive leaf extract safe?

Generally well tolerated, with occasional mild stomach upset or headache. The main cautions involve blood pressure and blood sugar.

Who should be careful with it?

People on blood-pressure or diabetes medication, and those who are pregnant or breastfeeding, should check with a doctor first.