Fountain of Youth, with caveats

Resveratrol helps hearts in mice, but doesn’t reproduce all the benefits of low-calorie diets

A substance found in red wine and touted as the chemical equivalent of the fountain of youth probably acts more like a wellspring of health — with warning signs.

Resveratrol, as the chemical is known, does a pretty good job of mimicking some age-defying effects found in studies of animals on calorie-restricted diets.