Metabolic rate and physical development in children at risk of obesity.

Children of obese (group O) and normal-weight (group N) parents who took part in a study of metabolic rates and food intakes when 3-5 years old were restudied 12 years later. There were striking differences between the sexes. Among the 15 adolescent boys, parental obesity predicted more rapid growth (but not adiposity) and an earlier decline in resting metabolic rate (RMR)/kg body weight, and childhood energy intake/kg body weight was not predictive. Among the 10 girls, the opposite pattern was observed; childhood energy intake/kg predicted both body size and adiposity, and parental obesity had less predictive value. The sex differences are consistent with the earlier maturation of girls, and the growth differences with the hypothesis that a low RMR/kg body weight is associated with a precocious pattern of growth and development in children predisposed to obesity.