The physiological effects of the dietary polyphenol resveratrol are being extensively studied. Resveratrol has been proposed to promote healthy aging and to increase lifespan primarily through the activation of the class III histone deacetylases (sirtuins). Although its positive effects are evident in yeast and mice they still have to be confirmed in humans. The molecular mechanisms involved in the processes are not fully understood because resveratrol may have other targets than sirtuins and the direct activation of sirtuins by resveratrol is under debate.