Overweight in adolescents: exploring potential risk factors.

Objective: To estimate the prevalence of overweight and to identify associations with sociodemographic, biological and lifestyle factors in adolescents from Florianopolis, Santa Catarina, Brazil.

Methods: Cross-sectional study carried out in 2007 with a probabilistic sample of 1,590 schoolchildren aged from 11 to 14 years old. The prevalence of overweight, based on body mass index, was estimated by the Brazilian reference and the International Obesity Task Force (IOTF). Multivariate analysis expressed as odds ratios were used to identify associations with sociodemographic, biological and lifestyle factors among adolescents.

Results: The prevalence of overweight was 19.3% (24.5% in boys and 14.5% in girls) using the IOFT reference, and 25.8% (31.8% in boys and 20.5% in girls) by the Brazilian reference. Among male adolescents, overweight was positively associated with unbalanced food consumption and inactive commuting to school. Among girls, the factors associated with overweight were: mother's overweight, unbalanced food consumption and discordance between stages for sexual maturity indicators.

Conclusions: The consumption of foods with high nutritional value was a protective factor against overweight among adolescents. This finding reinforces the importance of actions aimed at changing behaviors related to the family environment by encouraging the incorporation of healthy eating and active leisure time.