"To lengthen thy life, lessen thy meals." - Benjamin Franklin, "Poor Richard's Almanack", June 1733
A widely discussed experimental trial in 1986 demonstrated that restricting the calorie intake of laboratory mice proportionally increased their lifespan compared to a group of non diet restricted mice.
The findings have since been accepted, and generalised to a range of other animals. Researchers are investigating the possibility of parallel physiological links in humans (see Roth et al below).
Recent research has demonstrated (see Bluher et al) that it is not reduced intake which influences longevity. This was done by studying animals which have their metabolism changed to reduce insulin uptake, consequently retaining the leanness of animals in the earlier studies. It was observed that these animals can have a normal dietary intake, but have a similarly increased lifespan.
This suggests that lifespan is increased for an organism if it can remain lean and if it can avoid any accumulation of fatty tissue: if this can be done while not diminishing dietary intake (as in some minority eating patterns, see e.g. Living foods diet or Joel Fuhrman) then the 'starvation diet' anticipated as an impossible requirement by earlier researchers is no longer a precondition of increased longevity.
The extension of these findings to human nutrition and longevity is as noted above still in progress.
See:
External link: