A study, reported in the British Medical Journal (BMJ, 2015), that asked 4,979 adolescents aged 13-15 if they thought they were too heavy, about right, or too light found that almost half of overweight or obese boys (47%) and a third (32%) of overweight or obese girls identified themselves as ‘about the right weight’ or ‘too light.”
In comparison, 83% of normal weight boys and 84% of normal weight girls correctly identified themselves as ‘about the right weight.”
The study found that overall 73% of those studied were in the normal weight range, 20% were overweight, and 7% were obese.
Jackson, S.E., Johnson, F., Croker, H. & Wardle, J. (2015) Weight Perceptions in a Population Sample of English Adolescents: Cause for Celebration or Concern? International Journal of Obesity. doi: 10.1038/ijo.2015.126.