Resveratrol (3,5,4'-trihydroxystilbene) is a stilbene polyphenol produced by plants in response to injury, UV radiation, or pathogen attack. It is best known to the general public for its presence in red wine (principally from grape skins), where it was proposed as an explanation for the "French Paradox" — the observation that French populations consuming relatively high-fat diets nonetheless showed lower cardiovascular disease rates than expected. This connection, widely popularized from the mid-1990s onward, made resveratrol one of the most famous supplement ingredients in the world.
The scientific basis for resveratrol is more nuanced than the popular narrative suggests. Resveratrol is a potent SIRT1 activator — it binds to and activates sirtuin-1, a NAD+-dependent histone deacetylase that regulates a wide range of processes associated with longevity, metabolic health, and stress resistance: mitochondrial biogenesis, DNA repair, anti-inflammatory gene expression, and autophagy. In animal models, particularly in yeast, worms, flies, and obese mice, resveratrol has extended lifespan substantially and improved metabolic parameters. These findings generated intense interest in the possibility of mimicking caloric restriction's longevity effects pharmacologically.
However, the translation to humans has been complicated by the same challenge that plagues much of the polyphenol literature: poor oral bioavailability. Resveratrol is rapidly metabolized by intestinal and hepatic enzymes to sulfate and glucuronide conjugates, with peak plasma levels of parent compound occurring within 30–60 minutes but declining sharply thereafter. Multiple human trials using standard resveratrol formulations have produced inconsistent results. Bioavailability-enhanced formulations (micronized resveratrol, phospholipid complexes such as Longevinex, matrix-embedding in piperine-containing formulations) produce substantially higher plasma levels.
An important chemical distinction: resveratrol exists as trans and cis isomers. Trans-resveratrol is the biologically active form; cis-resveratrol has substantially less activity. Quality supplements should specify trans-resveratrol content.