Resveratrol

is a phytoalexin produced naturally by several plants when under attack by pathogens such as bacteria or fungi.

Resveratrol has also been produced by chemical synthesis[1] and is sold as a nutritional supplement derived primarily from Japanese knotweed. In mouse and rat experiments, anti-cancer, anti-inflammatory, blood-sugar-lowering, chelating and other beneficial cardiovascular effects of resveratrol have been reported. Most of these results have yet to be replicated in humans. In the only positive human trial, extremely high doses (3–5 g) of resveratrol in a formulation have been necessary to significantly lower blood sugar.

Resveratrol is found in the skin of red grapes and is a constituent of red wine, but apparently not in sufficient amounts to explain the French paradox that the incidence of coronary heart disease is relatively low in southern France despite high dietary intake of saturated fats. Despite much speculation that resveratrol might extend lifespan, scientific data indicates that it has no impact on normal mammalian lifespan.

Resveratrol (3,4',5-trihydroxystilbene) belongs to a class of polyphenolic compounds called stilbenes. Some types of plants produce resveratrol and other stilbenes in response to stress, injury, fungal infection, or ultraviolet (UV) radiation. Resveratrol is a fat-soluble compound that occurs in a trans and a cis configuration (see below). Both cis- and trans-resveratrol also occur as glucosides (bound to a glucose molecule). Resveratrol-3-O-beta-glucoside is called piceid. Scientists became interested in exploring potential health benefits of resveratrol in 1992 when its presence was first reported in red wine, leading to speculation that resveratrol might help explain the “French Paradox” (see Cardiovascular Disease below). More recently, reports on the potential for resveratrol to inhibit the development of cancer and extend lifespan in cell culture and animal models have continued to generate scientific interest.