ABSTRACT
Many of the earliest efforts at dietary restriction used a rather rudimentary methodology of simply feeding experimental animals smaller portions of the same diet fed to ad libitum mice. As nutritional investigations progressed and became more refined, protein and carbohydrate intakes were adjusted so that experimental animals received proportionately equivalent amounts of these macronutrients. Epidemiological studies have been of limited use in helping to determine which strategies would be most effective in preventing cancer by dietary manipulation, whereas results of more than 5 decades of experiments with laboratory animals, in particular, the venerable mice and rats, have permitted us to begin to sort out the respective roles of dietary components in the development of cancer. A growing number of animal studies indicate that calorie intake is the single most critical variable in the influence of nutrition on the development of cancer.
