Here's another reason why that glass of red wine may be good for you: scientists have identified a possible mechanism of action. Apparently, an ingredient in red wine, resveratrol, activates sirtuin, a protein that restores chromosomes to proper functioning. According to a recent story in the New York Times:

A new insight into the reason for aging has been gained by scientists trying to understand how resveratrol, a minor ingredient of red wine, improves the health and lifespan of laboratory mice. They believe that the integrity of chromosomes is compromised as people age, and that resveratrol works by activating a protein known as sirtuin that restores the chromosomes to health.

The finding, published online Wednesday in the journal Cell, is from a group led by David Sinclair of the Harvard Medical School. It is part of a growing effort by biologists to understand the sirtuins and other powerful agents that control the settings on the living cell’s metabolism, like its handling of fats and response to insulin.
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