Objective: The study investigates the evolution of healthy behaviors (healthy eating and regular physical activity) in Brazilian adolescents during 2012 and 2015, and its associations with self-assessment of body weight and adoption of weight control attitudes, in the context of diverse household features, school environments, and regional characteristics.
Methods: Two cross-sectional surveys of Brazilian adolescents attending the ninth grade in 2012 and 2015 were gathered comprising a national sample. Data from 209,601 completed surveys were analyzed using robust error estimates of ordinary least squares regressions.
Results: Results showed that there was a decrease in the frequency of healthy foods consumption and recommended physical activity level between 2012 and 2015. The regression analyses revealed that healthy eating and physical activity were significantly higher for adolescents with normal weight perception (i.e., did not perceive themselves to have either low or excess body weight) and for adolescents who were male, were members of middle socioeconomic stratum families, and had mothers with college degrees. In addition, healthy eating was significantly higher for adolescents who did not wish to lose weight, did not watch TV while eating, went to public schools, and lived with both parents. Ethnic differences varied based on region, with healthy eating being significantly higher among black/mulato/indigenous adolescents in the South and Southeast regions, but significantly higher among white/yellow adolescents in the North region.
Conclusions: Ethnic and gender-related differences were identified in health behaviors and attitudes towards weight control of Brazilian adolescents. Findings indicate the relevance of individual characteristics combined with the influence of social networks for the adoption of healthy behaviors among adolescent students.
Level of evidence: Level IV, evidence obtained from multiple time series without intervention.
Keywords: Adolescents; Body weight; Eating habits; Health behavior; Physical activity.