In humans, the answer is, unfortunately, “we don’t know.”
However, a meta-analysis of 19 studies on species including yeast, nematode worms, mice, fruit flies, and fish indicated that resveratrol reduced the risk of death. Specifically, the risk of death during the average lifespan was around 49%–60% lower for worms, yeast, and killifish who were treated with resveratrol — fruit flies and mice didn’t seem to obtain a lifespan benefit.[1]
The longevity-promoting effects of resveratrol are often attributed to its ability to induce cells to clear out their dysfunctional components and proteins — a process known as autophagy — and reduce oxidative stress.[2] Resveratrol also seems to prevent age-related declines in neurocognitive function and physical capacity, which may contribute to a lower incidence of aging-associated diseases and extend the healthy lifespan (also known as “healthspan”).
In rodents, resveratrol protects against neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, and dementia, against the age-related decline in muscle mass and strength known as sarcopenia, and against cancers, infertility, and osteoporosis. Thus, although resveratrol seems promising for preventing diseases associated with aging in animals, its effects on healthspan and lifespan will need to be verified in randomized controlled studies of humans.[2]