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Olive leaf

Mediterranean leaf extract with RCT signal for modest blood pressure reduction, head-to-head non-inferiority to captopril.

Why

Olive leaf (Olea europaea) is a traditional Mediterranean remedy whose principal phenolic, oleuropein, has accumulated a clinical evidence base over the last 15 years. The Susalit RCT directly compared olive leaf extract with captopril for stage-1 hypertension and reported non-inferior blood pressure reductions over 8 weeks. Smaller bodies of work support lipid-modulating and antiviral effects, but the BP indication is the most robust.

How it works

Oleuropein is hydrolysed to hydroxytyrosol and elenolic acid in the gut. Hydroxytyrosol increases endothelial nitric oxide synthesis, has direct ACE-inhibitory activity, and modulates calcium channel function in vascular smooth muscle. Antioxidant effect protects LDL from oxidation.

Expected onset · BP effect emerges over 4–8 weeks

How to take

Dosage

Standardised extract: 500 mg twice daily (delivering ~20% oleuropein, ~100 mg/dose).

Timing

Twice daily with food

On the label

Standardised to oleuropein content (typically 16–20%). Named preparations: EFLA 943 (the extract used in the Susalit trial).

Ideal for

Adults with mild hypertension exploring botanical adjuncts; people drawn to Mediterranean-pattern eating.

Safety

Hypotensive effect additive with antihypertensives. Monitor. May lower blood glucose. Monitor in diabetes. Pregnancy data limited; avoid therapeutic doses. Mild GI upset and headache possible. Theoretical antiplatelet effect at high doses.

Evidence

At a glance

Susalit 2011 Phytomedicine RCT (n=232 stage-1 hypertension): olive leaf extract 500 mg twice daily was non-inferior to captopril 12.5–25 mg twice daily for systolic BP reduction over 8 weeks (-11.5 vs -13.7 mmHg). EFSA authorised an Article 14 health claim for olive polyphenols and protection of LDL particles from oxidative damage at ≥5 mg hydroxytyrosol per day.

Where to get it

Shop Olive leaf on Amazon

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