Resveratrol is an ingredient of red wine that may be at least partly responsible for this beneficial effect. Resveratrol is a polyphenol, a natural antioxidant that protects cells against dangerous, naturally occurring substances known as free radicals. Test-tube and observational studies have linked resveratrol to reduced rates of heart disease and cancer. Sources Resveratrol is not an essential nutrient. It is found in red wine as well as in red grape skins and seeds and purple grape juice.
Peanuts also contain a small amount of resveratrol.
Resveratrol supplements are available as well. Because there haven t been any clinical studies, the optimal therapeutic dosage hasn t been established for resveratrol. Based on animal studies, a reasonable therapeutic dosage of resveratrol might be about 500 mg daily. 5,6,7 Test-tube studies also suggest that resveratrol might have a number of properties that might make it helpful for preventing cancer . Maximum safe dosages for children, pregnant or nursing women, or those with severe liver or kidney disease have not been determined.