From Scientific American:
An organic compound found in grapes, berries and some nuts extended the life span of fish in a recent study. Nothobranchius furzeri lives an average of nine weeks in captivity but lacing its food with resveratrol boosted longevity by more than 50 percent.
Previous research had shown that resveratrol prolongs the life span of yeast and insects, but this study marks the first proof of its antiaging effects in a vertebrate. Neuroscientist Alessandro Cellerino and his colleagues at the Scuola Normale Superiore in Pisa, Italy, tested different doses of the compound on more than 150 fish. Thirty fish received a small dose in their regular food, 60 received a medium dose and 20 received a large helping; meanwhile, 47 control fish enjoyed their insect larvae meals sans resveratrol. The control and low-dose fish saw no benefits, but even the fish who received only a middling amount of the compound lived up to 27 percent longer.
More here.