Abstract
Food restriction (FR) is a well-recognized method of extending mean and maximum longevity of rodents, but the mode of its action remains to be uncovered. This article reviews the effect of FR on the physical-chemical properties and lipid peroxidizability of cellular membranes. FR prevents the age-dependent increase in microviscosity and peroxidizability of cellular membranes. It has been suggested that a decrease in the body temperature occurring in undernourished animals may play a fundamental role in the process. Indeed, the lowering of average body temperature occurring in FR animals may induce a modification in membrane lipid composition, stimulating the cells to counteract the rigidifying effect of lower temperature. Thus, membranes are maintained in a proper functional state by a mechanism similar to that found in poikilotherm animals.