Predictors of erroneous perception of being overweight among adolescents

Adolescents' perception of overweight often disagrees with objective measurements; if factors explaining this discrepancy are potentially modifiable is unclear.

We analyzed cross-sectional data from a cohort of 2,001 Swedish adolescents (1,026 females, 975 males) at the age of 15 years in 2003. Erroneous perception of overweight was defined as the perception of being overweight in relation to normal or lower than normal BMI (kg/m(2)). BMI measured by the school nurse at 11 years, school-based education on nutrition/physical activity, smoking, alcohol consumption, physical activity, and healthy/unhealthy eating were examined as potential predictors/correlates of overweight misperception in multivariate logistic regression models.

At the age of 15 years, 32% of girls and 10% of boys misclassified themselves as overweight. Overweight at 11 years predicted misperception of overweight 4 years later (adjusted odds ratio (OR) = 2.3, 95% confidence interval (95% CI) = 1.4-3.6 in boys; OR = 1.9, 95% CI = 1.3-2.8 in girls). Among girls, smoking was associated with a higher probability of misperception (adjusted OR = 1.6, 95% CI = 1.2-2.2). Among boys, physical activity (>6 h/ week) was associated with a lower probability of misperception (OR = 0.4, 95% CI = 0.2-0.7). No association was observed with school-based education on nutrition and physical activity.

Preventing overweight in pre-adolescence may be a way to avoid later unjustified weight concerns in adolescence.