Healthy School, Happy School: Design and Protocol for a Randomized Clinical Trial Designed to Prevent Weight Gain in Children

BACKGROUND: Schools have become a key figure for the promotion of health and obesity interventions, bringing the development of critical awareness to the construction and promotion of a healthy diet, physical activity, and the monitoring of the nutritional status in childhood and adolescence. OBJECTIVES: To describe a study protocol to evaluate the effectiveness of an intervention designed to improve knowledge of food choices in the school environment. METHODS: This is a cluster-randomized, parallel, two-arm study conducted in public elementary and middle schools in Brazil. Participants will be children and adolescents between the ages of 5 and 15 years, from both genders. The interventions will be focusing on changes in lifestyle, physical activities and nutritional education. Intervention activities will occur monthly in the school’s multimedia room or sports court. The control group arm will receive usual recommendations by the school. The primary outcome variable will be anthropometric measures, such as body mass index percentiles and levels of physical activity by the International Physical Activity Questionnaire. RESULTS: We expect that after the study children will increase the ingestion of fresh food, reduce excessive consumption of sugary and processed foods, and reduce the hours of sedentary activities. CONCLUSION: The purpose of starting the dietary intervention at this stage of life is to develop a knowledge that will enable for healthy choices, providing opportunities for a better future for this population.