Metabolic impact of obesity in childhood.

Childhood and adolescent obesity have become the most prevalent nutritional diseases in the United States. The results of a number of studies demonstrate that the metabolic alterations caused by excess body fat are expressed early in the natural history of obesity. Such alterations seem clinically important even in children, as evidenced by the recent increase in type 2 diabetes in obese adolescents. These observations underscore the need for research efforts directed at the development of effective interventions to stem the tide of the childhood obesity epidemic.