The teenager, from Renfrew near Glasgow, is so worried about his appearance that he photoshops all of his online profile pictures.
Almost a third of 2,000 UK teenagers, polled for a body confidence campaign, avoid activities like PE because of fears about their looks.
The Be Real Campaign says schools have a key role in combating body anxiety.
Fears about they way they look are "having a profoundly negative effect on a significant number of young people in the UK", says the report.
