EFFECTS OF CYCLES OF FOOD RESTRICTION FOLLOWED BY AD-LIBITUM REFEEDING ON BODY-COMPOSITION AND ENERGY-EXPENDITURE IN OBESE RATS

Male Wistar rats rendered obese by a cafeteria diet were subjected to three successive cycles alternating food restriction with ad libitum cafeteria-diet feeding (WC rats). Body composition, energy intake, energy required for maintenance, and oxygen consumption were studied. Results were compared with those for rats fed a standard stock diet (CON rats) or a cafeteria diet (CAF rats). The rate of weight loss or regain was independent of the number of cycles. WC rats were fatter than CON rats and as fat as CAF rats after the third cycle. Cost of maintenance of WC rats decreased; their oxygen consumption decreased in the lean state, increased again in the fat state, but remained lower than that of CON and CAF rats. We conclude that the practice of successive restriction and refeeding did not result in resistance to weight loss, but rather in a defect in the utilization of energy intake, facilitating the development of obesity.