Secular trends in weight status and weight-related attitudes and behaviors in adolescents from 1999 to 2010

Objective. To examine secular trends from 1999 to 2010 in weight status and weight-related attitudes and behaviors among adolescents. Methods. A repeated cross-sectional design was used. Participants were from Minneapolis/St. Paul middle schools and high schools and included 3072 adolescents in 1999 (mean age 14.6 +/- 1.8) and 2793 adolescents in 2010 (mean age 14.4 +/- 2.0). Trends in weight-related variables were examined using inverse probability weighting to control for changes in socio-demographics over time. Results. The prevalence of obesity among boys increased by 7.8% from 1999 to 2010, with large ethnic/racial disparities. In black boys the prevalence of obesity increased from 14.4% to 21.5% and among Hispanic boys, obesity prevalence increased from 19.7% to 33.6%. Trends were more positive among girls: weight status did not significantly increase, perceptions of overweight status were more accurate, the use of healthy weight control behaviors remained high, dieting decreased by 6.7%, unhealthy weight control behaviors decreased by 8.2% and extreme weight control behaviors decreased by 4.5%. Conclusions. Trends indicate a need to intensify efforts to prevent obesity and other weight-related problems, particularly for boys from ethnic/racial minorities. The decreases in unhealthy weight control behaviors among girls are encouraging. (C) 2011 Elsevier Inc. All rights reserved.