[Evaluation of an education intervention for childhood obesity prevention in basic schools in Chile].

The aim of this study was to evaluate a comprehensive intervention in nutrition education and physical activity to prevent childhood obesity in primary school children of low socioeconomic status in Macul county in Chile, with a two year follow-up (2008 and 2009) of the children. The intervention consisted in teacher nutrition training in healthy eating and the implementation of educational material based on Chilean dietary guidelines. In addition, there was an increase in physical education classes to 3-4 hours per week and physical education teachers were recruited for that purpose. Weight, height and six minutes walk test (6MWT) were measured and body mass index (BMI), BMI Z score, prevalence of normal, overweight and obese children were calculated with WHO 2007reference. Changes between baseline and BMI Z in each period and 6MWT/height, and changes in nutrition knowledge through questionnaires were measured. There was no significant difference in BMI Z score between the initial and final periods and in the evolution of the nutritional status of children. Nutrition knowledge improved significantly between the two measurements. There was a significant increase in 6MWT/height (10 meters between baseline and follow-up, p < 0.001). We conclude that although there was an improvement in nutrition knowledge and physical fitness of children, there was a stabilization of BMI Z score in the period of the study. New educational interventions are required according to the reality of each community to obtain a positive impact to prevent childhood obesity in primary schools.