Resveratrol (trans-resveratrol) is a phytoalexin produced naturally by several plants when under attack by pathogens such as bacteria or fungi.
Resveratrol is currently a topic of numerous animal and human studies into its effects. The effects of resveratrol on the lifespan of many model organisms remain controversial, with uncertain effects in fruit flies, nematode worms, and short-lived fish. In mouse and rat experiments, anti-cancer, anti-inflammatory, blood-sugar-lowering 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 proprietary formulation have been necessary to significantly lower blood sugar. Despite mainstream press alleging resveratrol's anti-aging effects, there exists no scientific evidence for the application of these claims to mammals.