Research

Hormonal

Supplementation with olive leaf extract (51.1 mg oleuropein and 9.7 mg hydroxytyrosol daily) for 12 weeks significantly improves insulin sensitivity and pancreatic beta-cell responsiveness in overweight middle-aged men.

If you are an overweight man between 35 and 55 years old, taking olive leaf extract containing roughly 51 mg of oleuropein and 10 mg of hydroxytyrosol daily for 12 weeks may improve your body's ability to use insulin and manage blood sugar. This benefit was observed when participants maintained their usual diet and exercise habits, suggesting the supplement itself drives the change. It is not a substitute for medical advice but may offer a beneficial adjunct for metabolic health.

GoodSupportsHIGH confidence
OLE supplementation was associated with a 15% improvement in insulin sensitivity (p = 0.024)... There was also a 28% improvement in pancreatic b-cell responsiveness (p = 0.013).
Martin de Bock et al. · PLoS ONE · 2013

Why this rating

Randomized, double-blinded, placebo-controlled crossover trial with high compliance and validated measures (Matsuda index), though limited to a specific demographic.

Source

Olive (Olea europaea L.) Leaf Polyphenols Improve Insulin Sensitivity in Middle-Aged Overweight Men: A Randomized, Placebo-Controlled, Crossover Trial

Martin de Bock et al. · PLoS ONE · 2013

DOI 10.1371/journal.pone.0057622

crossover · n=46Cited 301×
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DOI resolved against Crossref · corpus check 2026-06-10

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