[Effectiveness of population-based interventions on the prevention of overweight in children and adolescents]

This study aimed to assess the available scientific evidence on the effectiveness or cost-effectiveness of interventions to prevent obesity, carried out in child and adolescent population. We conducted a systematic review, searching 10 databases and other resource directories for the period January 1998-July 2008. We assessed study quality and extracted and summarized information that met the established criteria. Results included 40 studies that evaluated interventions showing mostly components of physical activity, nutrition and education. We found no evaluations of cost-effectiveness. Thirteen studies resulted in a significant reduction in favor of intervention in some of the anthropometric measurements. In conclusion, some interventions showed an impact in preventing weight gain. However, it is weak, since most studies have not had the expected result, were heterogeneous and of short duration.