FRAR course on laboratory approaches to aging. Nutrition, including diet restriction, in mammals.

Although diet influences basic aging processes as well as age-associated disease processes, diet is either not mentioned or inadequately described in reports of gerontologic studies using animal models. Studies carried out in our laboratory with male F344 rats are a good example of the importance of diet in the use of an animal model for aging research. Nephropathy, resulting in kidney failure, is often an overwhelming disease problem in life span studies using ad libitum fed male F344 rats. However, by appropriate choice of dietary components, nephropathy can be reduced to only one of several disease processes contributing to the death of these ad libitum fed rats. Such diets greatly increase the value of the male F344 rat as a model for aging research. Because almost all rodent species and strains suffer from one or more major age-associated diseases, nutritional conditions should be sought in the case of each to minimize the occurrence of such diseases during an aging study. Restriction of energy intake (often called food restriction or dietary restriction) delays or prevents most age-associated disease processes in a spectrum of rat and mouse strains. It is, therefore, suggested that the dietary restricted rodent be used as the standard or base model for aging research. Moreover, dietary restriction is proving to be a powerful tool for the study of aging processes.