Grape Seed Extract (GSE)
Commonly used for
Heart Health
Where to Buy
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The cheapest product is usually low quality, but more expensive doesn’t always mean better.
What is it? / Overview
Grape seed extract is rich in oligomeric proanthocyanidins (OPCs), potent polyphenols that improve endothelial function and reduce oxidative stress. Clinical trials demonstrate modest improvements in blood pressure and vascular health, particularly in those with elevated cardiovascular risk.
How is it used? / Administration
Form: Standardized extract, ≥90–95% oligomeric proanthocyanidins (OPCs)
Typical dose studied: 150–300 mg/day
Timing: With meals
Choose standardized OPC extracts. Often combined with other polyphenols for vascular health.
How well does it work? / Evidence
~ Moderate evidence
Who should avoid it?
Avoid with: Bleeding disorder / Coagulopathy
Interacts with: Anticoagulants; Antiplatelet medications; Antihypertensives — monitor
Already taking it? Assess benefit after 8–12 weeks.
Research & references
Feringa HHH et al. (2011). Grape seed extract and cardiovascular risk markers meta-analysis. Journal of the American Dietetic Association. Zhang H et al. (2016). Grape seed extract and blood pressure meta-analysis. Medicine. Angelopoulos N et al. (2023). CoQ10, grape seed, and olive leaf extracts lower LDL RCT. Nutrients.
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