Food restriction, evolution and ageing.

The food restriction model for life extension is nearing "three-score and 10" years of age and remains in good shape, preserving much of the mystique of its youth. Although originally described for laboratory rodents, recent work shows that food restriction also appears to slow ageing processes in a range of other animal species, raising the question of whether this response represents some generalised evolutionary adaptation, perhaps a strategy to cope with periods of famine. If the food restriction response does have an adaptive basis, this would suggest that specific gene regulatory processes have evolved to shape the organism's physiological response to food restriction. It will then be important to investigate how these are organised and whether the same or different factors are at play in the various species in which food restriction extends life span.