The Association between Body Weight Misclassification in Adolescence and Body Fat and Waist Circumference in Adulthood: A Longitudinal Study.

This study examined the longitudinal association between adolescent body weight misclassifications and body fat and waist circumference during adulthood. A sample was derived from a large Australian birth cohort study. The data analyses were restricted to 1002 participants for whom data on both measured and perceived weight at a 14-year follow-up and the actual measure of adult body fat and waist circumference at a 30-year follow-up were available. To determine misclassifications, we compared the perceived weight with the measured weight. The results were presented as means and mean differences (with a 95% confidence interval) of the body fat percentages and waist circumference levels across the weight misclassification groups, adjusting for potential covariates. For both male and female adolescents, weight underestimation was significantly associated with an increase in body fat percentages and waist circumference in adulthood as compared to those who correctly estimated their weight. In the mean difference analyses, adolescent males and females who underestimated their weight were found to have significantly higher body fat, and waist circumference means than those who correctly estimated their weight in the unadjusted and adjusted comparisons. The adolescent males who overestimated their weight had higher body fat, and waist circumference means when they reached adulthood. Increased awareness of weight misclassification and actual weight among adolescents might contribute to better control of weight gain in adulthood.