Healthy Habits, Healthy Girls Preventing Unhealthy Weight Gain

Healthy Habits, Healthy Girls: a Intervention Program for Adolescent Girls From Disadvantaged Backgrounds

The purpose of this study is to evaluate the impact of a multicomponent school-based intervention based on Bandura's Social Cognitive Theory targeting healthy eating and physical activity for high school adolescent girls from low-income communities in the city of São Paulo, Brazil.

The "Healthy Habits, Healthy Girls" is a 6-month multi-component school-based intervention developed in reference to Social Cognitive Theory and includes: (1) enhanced physical education classes (2x/week and delivered by a Physical Education teacher), (2) break/lunch-time physical activity sessions (the participating girls will encourage younger girls to make Physical Activity during break and/or lunch-time. This session will only happen after 3 months of enhanced Physical Education classes, so the girls will be able to pass their knowledge for the others), (3) Nutrition and Physical Activity handbooks with 10 health messages (lessons to be done at home and their family); (4) 4 Parent newsletters; (5) Food and Physical Activity diaries for self-monitoring; (6) text-messages using a group application for more interaction and social support; and (7) 10 weekly Nutrition and Physical Activity key messages (delivered by a Nutrition and Dietetics Bachelor degree and/or Physical Education teacher during break). The intervention will be evaluated using a randomised controlled trial in 10 public schools in the city of São Paulo, Brazil (5 control and 5 intervention) and based on the 10 weekly key messages: (1) eat fruit and vegetables daily; (2) Do Physical Activity respecting your limits; (3) Eat a healthy breakfast every day; (4) Do Physical Activity with your family and friends; (5) Control the portion size you eat during meals - and sit while you are eating; (6) Reduce your sitting time during school break, after the school period and on the weekends; (7) Have less "junk food" for meals/snacks and munch less; (8) Identify the excuses for not practicing PA; (9) Drink water and substitute sodas and artificial juices for water, homemade natural fruit juices and coconut water, and; (10)Make family meals.

Inclusion Criteria:

- Adolescent girls from low-income backgrounds enrolled in high schools of the city of São Paulo, Brazil.

Exclusion Criteria:

• Adolescent boys
• Adolescents from middle and high income backgrounds
• Pregnant