Calorie restriction

Calorie restriction is the most proven method of extending life span. 
Calorie restriction causes inhibition of insulin signalling path.?
See: CR in rodents.
It is known since 1917 that CR extends life span
Osborne TB, Mendel LB, Ferry EL. «The effect of retardation of growth upon the breeding period and duration of life of rats.» Science 1917; 45:294-5.
See: Stunt; Stuning; Delaying degeneration