Children, particularly adolescents, who are obese, have a high probability of becoming adults who are obese; hence, the bimodal distribution of obesity portends a large-scale obesity epidemic in the next few decades. Taller children generally tend to be more obese than shorter peers, are more insulin-resistant, and have increased leptin levels. Adolescent obesity poses a serious risk for severe obesity during early adulthood, particularly in non-Hispanic black women. This calls for a stronger emphasis on weight reduction during early adolescence, specifically targeting groups at greater risk.