Body mass index, overweight and obesity in adolescents in Europe and the United States.

Overweight and obesity have increased globally among children, adolescents, and adults. The World Health Organization (WHO) designates obesity as one of the most important public health threats because of the significant impact of chronic conditions associated with obesity. Obesity in adults increases the risk of cardiovascular diseases, diabetes, and musculoskeletal disorders. Obesity is less prominently associated with morbidity in adolescence but is a strong precursor of obesity and related morbidity in adulthood, with 50% to 80% of obese teenagers becoming obese as adults. During adolescence, overweight and obesity are often a burden that results in psychosocial problems and a reduced capacity for physical activity. Adolescence is a critical period for the onset of obesity and for obesity-associated morbidity in later life. Therefore, from a public health perspective, it is important to monitor overweight in adolescence.