Overweight and obesity in youth is a worldwide public health problem. Overweight and obesity in childhood and adolescents have a substantial effect upon many systems, resulting in clinical conditions such as metabolic syndrome, early atherosclerosis, dyslipidemia, hypertension and type 2 diabetes (T2D). Obesity and the type of body fat distribution are still the core aspects of insulin resistance and seem to be the physiopathologic links common to metabolic syndrome, cardiovascular disease and T2D. The earlier the appearance of the clustering of risk factors and the higher the time of exposure, the greater will be the chance of developing coronary disease with a more severe endpoint. The age when the event may occur seems to be related to the presence and aggregation of risk factors throughout life.The treatment in this age-group is non pharmacological and aims at promoting changes in lifestyle. However, pharmacological treatments are indicated in special situations.The major goals in dietary treatments are not only limited to weight loss, but also to an improvement in the quality of life. Modification of risk factors associated to comorbidities, personal satisfaction of the child or adolescent and trying to establish healthy life habits from an early age are also important. There is a continuous debate on the best possible exercise to do, for children or adolescents, in order to lose weight. The prescription of physical activity to children and adolescents requires extensive integrated work among multidisciplinary teams, patients and their families, in order to reach therapeutic success.The most important conclusion drawn from this symposium was that if the growing prevalence of overweight and obesity continues at this pace, the result will be a population of children and adolescents with metabolic syndrome. This would lead to high mortality rates in young adults, changing the current increasing trend of worldwide longevity. Government actions and a better understanding of the causes of this problem must be implemented worldwide, by aiming at the prevention of obesity in children and adolescents.