Secular changes in overweight and obesity among Brazilian adolescents from 1974/75 to 2002/03

This chapter describes the prevalence, distribution, and changing trends of overweight and obesity among Brazilian adolescents across the last three decades, including the most recent population study from 2002 to 2003. Increases in height, weight, and BMI were observed in both genders and across all time periods and income groups. Among males, the prevalence of overweight and obesity increased consistently during all three time periods and among all income groups. Among females, overweight and obesity increased in the early studies, but tended to decrease in more recent years and this trend was particularly marked in the higher income groups. The chapter suggests that improved nutrition and infant health in conjunction with better social and educational conditions may have influenced the increase in height, weight, and overweight among Brazilian children and adolescents over the past few decades. The recent decrease in overweight and obesity among young females may be explained by the social pressure for a slim body. Further studies should investigate these trends and should particularly focus on explaining the socioeconomic factors which appear to impact on childhood obesity.