The school as an opportunity for obesity prevention: An experience from the Mexican school system

Background: 26% of school children in Mexico are overweight or obese (OW/OB), which means a 33% increase in 7 years. Objective: To design, implement and evaluate a strategy to modify the school environment in order to promote healthy lifestyles through physical activity and food habits to prevent OW/OB in children in public schools in Mexico city. Methods: Formative research to diagnose the environment and design the intervention. Evaluation by means of an experimental design in randomly selected intervention and control schools. Results: School environment contributes to energy imbalance, promotes consumption of energy dense foods and beverages and limits the opportunities to practice physical activity. Strategies focused on food habits, physical activity and communication were implemented during two school years in 16 schools. The intervention reduced the offer of energy dense foods, increased the availability of fruits, vegetables and water to drink. Limited changes were observed at individual level, although changes show a trend towards positive effects of the intervention on behaviours and their determinants. Conclusion: The intervention modified the school environment but a more intense and permanent effort is required to change behaviours at individual level. (C) 2009 SENC. Published by Elsevier Espana, S.L. All rights reserved.