BACKGROUND Key aspects in a lifestyle analysis are physical activity level and eating habits. An unhealthy lifestyle results in fat mass increase and in a predisposition to non communicable chronic diseases even in young age. The purpose of this study was to investigate the lifestyle and body composition in young athletes. METHODS The subjects underwent to an assessment of body composition and they completed two questionnaires, one concerning the level of physical activity and the other regarding eating habits. RESULTS 152 young athletes (63 females and 89 males) aged 8 to 18 years (13.4±2.5 years, height 159±14 cm) were enrolled in this study. 80.3% of subjects were normal weight (13.4±2.6 yrs) and 19.7% subjects (13.5±2.5 yrs) were overweight or obese. Greater sedentary behaviors were found in the overweight or obese participants compared to normal weight (618±125 vs 523±89 min; p<0.001) and a lower consumption of milk and yoghurt (5.0±3.2 vs 6.9±4.1 times/week; p=0.031). CONCLUSIONS Although competitive sports often increases physical activity levels in young people, this activity does not seem to reach the daily recommended amount of physical activity during youth. Therefore, it is necessary to have a comprehensive approach to create a primary prevention strategy from even a young age.