Nutritional status, body image, and their association with extreme weight control behaviors among Brazilian adolescents, National Adolescent Student Health Survey 2015.

INTRODUCTION: This study aimed to analyze the association between nutritional status, body image perception, and extreme weight control behaviors among adolescents.

METHODS: This is an analytical cross-sectional study conducted in Brazil based on the National Adolescent Student Health Survey (Pesquisa Nacional de Saúde do Escolar - PeNSE) of 2015, with adolescents aged 13 to 17 years. Nutritional status and body image perception were the independent variables. The two dependent variables were vomiting or laxative use and use of medicines and other formulas for weight control in the 30 days prior to data collection. We used Poisson regression models for association, with demographic variables for control.

RESULTS: 7.4% of adolescents (95%CI 6.7 - 8.2) reported vomiting or using laxatives, with no difference between genders. The prevalence of use of medicines and formulas was higher among boys (7.8%; 95%CI 6.6 - 8.9). The association between nutritional status and extreme behaviors was not significant. However, the prevalence of vomiting or laxative use for adolescents who considered themselves very fat was 2.3 (95%CI 1.1 - 4.7) times higher for boys and 5.3 (95%CI 3.3 - 8.6) times higher for girls, while the use of medicines and formulas was 4.0 (95%CI 2.3 - 7.1) times higher for girls who considered themselves very fat.

CONCLUSION: Body image perception seems to have a greater influence on extreme behaviors than nutritional status. Strategies involving health services and schools have great potential to impact the self-esteem and health of students positively.