The dietary patterns of sixty-four adolescents (thirty-seven young men and twenty-seven young women) between 15 and 17 years of age were examined by analysis of food, energy and nutrient ntakes, over a period of 5 d, including a Sunday. Adolescents were dentified for inclusion in two study groups: (1) overweight and obese subjects (O) with a BMI (kg/m2) ≥ 75th percentile, and (2) subjects of normal weight (NW) with BMI < 75th percentile. The study was designed to investigate the differences between the energy and nutrient intakes of NW and O adolescents. No differences were found in energy intake between NW and O adolescents. However, O subjects derived a greater proportion of their energy from proteins (19.8% v 16.4% for NW subjects) and fats (45.4% v. 38.7% for NW subjects), and less from carbohydrates (34.6% v. 44.6% for NW subjects). Also, O subjects consumed significantly larger amounts of cholesterol. In order to prevent obesity and avoid the disorders associated with this condition, it appears necessary not only to regulate energy intake, but also to control the composition of the diet. Given that it is during infancy that feeding habits are developed, it is important to ensure that correct habits are acquired. Special attention should be given to improving the dietary habits of overweight and obese children and adolescents.