Factors associated with weight loss dieting among adolescents: the 11-year follow-up of the 1993 Pelotas (Brazil) birth cohort study.

Evidence has shown the negative effects of unsupervised diets and those with excessive calorie restriction. The aim of this study was to determine the proportion of adolescents engaging in weight loss dieting and associated factors. This was a cross-sectional study of 4,452 adolescents born in Pelotas, Rio Grande do Sul State, Brazil, in 1993. The outcome was defined as adolescents that reported having practiced some type of weight loss dieting in the previous 12 months. Prevalence of such dieting was 8.6% (95%CI: 7.7;9.4), and was higher in girls. Elevated maternal body mass index (BMI) was associated with dieting among girls. The adolescent's and parents' view of the adolescent's weight, excess weight, and consumption of diet or light soft drinks were associated with adolescent dieting. There was a positive association between dieting and socioeconomic status. The findings provide important backing for policies aimed at improving adolescents' diet, since they express a major concern over weight and thus a significant percentage of individuals with erroneous and unhealthy behaviors.