Parents and doctors who assume eating disorders very rarely affect males, should reconsider again.
A study of 5,527 teenage males from across the US, challenges this belief.
Boston Children's Hospital researchers found 17.9 percent of adolescent boys were extremely concerned about their weight and physique.
These boys were more likely to start engaging in risky behaviors, including drug use and frequent binge drinking.
"Males and females have very different concerns about their weight and appearance," the study's lead author Alison Field, ScD, from Boston Children's Hospital Adolescent Medicine Division, said.
Evaluations for eating disorders have been developed to reflect girls' concerns with thinness but not boys' concerns, which may be more focused on muscularity than thinness.
To better understand how symptoms of eating disorders might be linked to obesity, drug use and depression in males, Field and her colleagues reviewed responses to questionnaires completed as part of the Growing Up Today Study. Teens responded to surveys every 12 to 36 months from 1999 through 2010.
Boys tended to be more interested in muscularity than thinness, with 9.2 percent of males reporting high concerns with muscularity, compared with 2.5 percent concerned about thinness and 6.3 percent concerned with both aspects of appearance.
Males concerned about muscularity and who used potentially unhealthy supplements, growth hormone and steroids to enhance their physique were approximately twice as likely to start binge drinking frequently and much more likely than their peers to start using drugs.
Boys concerned with thinness were more likely to develop depressive symptoms.
A total of 2.9 percent of all respondents had full or partial criteria binge-eating disorder, and nearly one-third reported infrequent binge eating, purging or overeating.
Anorexia nervosa and bulimia nervosa are characterized by an excessive influence of weight and physique on self-evaluation, with patients focused on being thin or wanting to losing weight.
Most eating disorder assessments reflect this desire for thinness and may overlook boys concerned about their weight and shape but who want to be more muscular.
This may be the male equivalent of girls who are very concerned with their weight and who use vomiting or laxatives for weight control, according to Field.
The study is published in JAMA Pediatrics.