Association between selected individual and environmental characteristics in relation to health behavior of Brazilian adolescents.

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.

Sociodemographic determinants of health behaviors among Brazilian adolescents: Trends in physical activity and food consumption, 2009-2015.

INTRODUCTION: Food consumption habits and physical activity levels are health behaviors influenced by sociocultural factors during adolescence. This study analyzes the trends and the sociodemographic determinants in the adoption of health behaviors among students in Brazilian state capitals regarding frequencies of consumption of healthy and unhealthy foods and level of physical activity in 2009, 2012 and 2015. METHODS: This study comprises an investigation of three editions of a cross-sectional survey conducted, at national level, by the Brazilian Institute for Geography and Statistics in partnership with the Brazilian Ministry of Health. Students attending elementary school ninth grade in public and private schools were selected using two stage sampling process to participate in the survey in 2009, 2012 and 2015. We selected variables that were comparable in the three editions of the survey, including individual-level sociodemographic and behavioral features, and household-level family and geographical characteristics. The dependent variables selected for multivariate logistic regression models included physical activity levels and frequencies of healthy and unhealthy foods consumption. RESULTS: Male adolescents from higher socioeconomic strata in 2009 and 2015 and students who declared frequent consumption of healthy foods were more likely to practice physical activities. However, there was a significant decrease in physical activity among Brazilian adolescents during the period analyzed, independently of socioeconomic strata. Healthy eating patterns were observed among non-white adolescents, students who declared having meals with their parents, and individuals who fulfill recommendations of physical activity level throughout the week. On the other hand, unhealthy eating pattern was more frequently observed among female adolescents and students who declared having meals while watching television. CONCLUSION: Evidence shows limited effects of socioeconomic level on the adoption of healthy behaviors among adolescents in Brazil, and influence of family practices on the establishment of healthy food consumption patterns (e.g., presence of parents and absence of practices like watching television during meals).