Energy need for weight maintenance in human beings: effect of body size and composition

We estimated energy requirement by determining the amount of food needed to maintain body weight in a controlled environment. In a study of 28 adolescents and adults of widely varying weight and body fat content, we found that the energy required for weight maintenance was directly proportional to body weight (r = 0.92). The increased energy requirement of the obese is due in part to their larger lean weight and in part to their greater burden of body fat; together these account for 87% of the variance. For these subjects, who were engaged in light physical activity, the ratio of total energy to basal metabolic rate was 1.52 +/- 0.16 (SD).