Drink milk and live longer?

An interesting article is summarized in the Research Highlights section of the May 10 issue of Nature Magazine:

In yeast at least, the molecular pathway that extends an organism's life when it is put on a diet can be induced — without calorie restriction — by a vitamin found in milk. So says a team led by Charles Brenner from Dartmouth Medical School in Lebanon, New Hampshire, and Jeffrey Smith from the University of Virginia Health System in Charlottesville. (Cell, Volume 129, Issue 3, Pages 473-484)

The researchers showed that the vitamin, called nicotinamide riboside, raises in yeast the levels of a molecule known as NAD (nicotinamide adenine dinucleotide). This, in turn, activates the anti-ageing protein Sir2. Yeast make use of the vitamin through molecular pathways that have some genes in common with humans, raising the possibility that supplements could be designed to enhance humans' longevity.