• adolescent;
  • behaviour;
  • overweight;
  • perception;
  • psychological

Aim:  To compare overweight and obese adolescents with accurate and inaccurate self-reported weight perception across a range of behaviours and measures of psychological well-being.

Methods:  This study uses a cross-sectional survey of grade 7–12 high school students in New South Wales, Australia, conducted in 2008 (n= 7553). Overweight and obese students based on body mass index were classified as accurate perceivers (weight perception was ‘too fat’) or inaccurate perceivers (weight perception was ‘about right’).

Results:  Nearly a third of adolescents had incongruity between self-perceived body weight status and body mass index-determined weight category. Compared with boys, girls were less likely to underestimate their body weight (odds ratio: 0.26; 95% confidence interval: 0.25, 0.27) and more likely to overestimate their body weight (odds ratio: 3.4; 95% confidence interval: 3.3, 3.5). Accurate body weight perception was higher in obese adolescents compared with overweight adolescents (69.5% vs. 44.0%). Compared with mis-perceivers, accurate overweight and obese perceivers had significantly higher odds of trying to lose weight and being more physically active; however, they showed a combination of unhealthy and healthy behaviours (i.e. dietary patterns and sedentary activities). Accurate weight perception among overweight and obese adolescents was associated with increased odds of feeling sad or depressed in the past 6 months.

Conclusions:  Further research on social, familial and psychological factors that predict or mediate healthy and unhealthy weight-related behaviours among adolescents by accuracy of weight perception is needed. Accurate weight perception should be considered in counselling and behavioural interventions.