Influence of Diet Composition on Caloric Requirements, Water Intake and Organ Weights of Rats during Restricted Food Intake

Abstract

The influence of high-fat, high-carbohydrate, and high-protein diets on the caloric requirements, water intake, and organ weights of rats kept at constant weight by restricted feeding was studied. The caloric requirements for all diets declined during the first 5 weeks and became constant thereafter. One the high-protein and high-fat diets, the animals were eventually able to maintain their weight with 25% fewer calories than those on the high-carbohydrate diet. The water intake was highest on the high-protein and lowest on the high-fat diet. The adrenal weights of the animals on the high-fat diet were higher, on the average, than those of the animals on the high-carbohydrate diet, with those of the high-protein rats being in between. The renal weights were highest among the high-protein animals. The testicular weight of the high-fat animals was significantly higher than that of the animals on the high-carbohydrate diet.