Science 326, 140–144 (2009)

Caloric restriction extends the lifespan of many model organisms, a finding that has prompted some people to drastically reduce their food intake in the hope of upping their longevity. But how exactly caloric restriction staves off death remains unknown.

Dominic Withers of University College London and his colleagues found that mice in which the gene S6k1 was deleted lived for about 80 days — or 9% — longer than control mice, with females surviving 20% longer. The animals were also less likely to develop certain signs of ageing, such as loss of insulin sensitivity. The gene-expression patterns of the mice were similar to those in mice undergoing long-term caloric restriction, suggesting that manipulating S6K1 signalling could be a strategy for researchers seeking drugs that mimic the positive effects of this regime.