Grape Seed Extract — The Vascular Protector

Grape seed extract is rich in oligomeric proanthocyanidins (OPCs), which are potent antioxidants. It modulates endothelial nitric oxide synthase (eNOS), increasing nitric oxide production and promoting vasodilation. OPCs also inhibit inflammatory pathways, including NF-κB, and reduce oxidative stress by scavenging free radicals. In preclinical models, it has been shown to improve multi-organ dysfunction and reduce age-associated oxidative stress and inflammation.

Multiple human trials have investigated grape seed extract for cardiovascular and metabolic health. A 2011 meta-analysis in the Journal of the American Dietetic Association found it significantly lowers systolic blood pressure and heart rate. A 2009 trial in Diabetic Medicine showed that 600 mg/day improved markers of inflammation (hsCRP) and glycaemia in Type 2 diabetic subjects at high cardiovascular risk. No published human longevity trials exist.

150–600 mg/day is the most studied range in humans for cardiovascular and metabolic benefits. Some safety studies have used up to 2,500 mg/day without significant adverse effects. Best taken with meals to improve absorption and reduce potential gastrointestinal discomfort.

Generally well tolerated at doses up to 2,500 mg/day. Mild side effects may include headache, dry scalp, dizziness, and nausea. Due to its potential to lower blood pressure and affect blood clotting, it should be used with caution in individuals taking antihypertensive medications or blood thinners. Avoid in individuals with a known allergy to grapes.

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