Utilization of Food for Weight Maintenance and Growth

Abstract

Food requirements for weight maintenance and weight increase were determined by measurements of the food intake of rats kept at constant weight by restricted feeding of a complete, purified diet and of the food intake and weight increase of well-matched rats permitted to eat freely of the same diet. The requirements for the maintenance of one gram of body weight were found to be influenced by the duration of food restriction, the body weight, and the room temperature but hardly by the age of the animals. Continued food restriction led to a reduction of about 30% in the weight maintenance requirements. Food requirements for weight increase did not seem to be influenced by the above factors. Approximately one gram of food was necessary to build one gram of body substance under widely different conditions. The implications of these findings for studies of food utilization and paired weighing and paired feeding techniques are discussed.