Eating disorders different in girls than boys

Risk factors for developing eating disorders are different for girls and boys, and a mother’s history may affect girls differently depending how old they are, a Boston study reports.

Alison E. Field of Children’s Hospital Boston and her colleagues report in the Archives of Pediatric and Adolescent Medicine on their study following more than 12,000 sons and daughters of participants in the Nurses Health Study II to see what influences might predict eating disorders. The girls and boys answered questionnaires every 12 or 18 months for seven years, starting when they were 9 to 15 years old. Their mothers were asked if they themselves had ever had an eating disorder.

After seven years, 10 percent of the girls and 3 percent of the boys said they were binge eating – overeating and feeling out of control -- or purging – vomiting or using laxatives to keep from gaining weight -- at least once a week. For girls, purging was more common than binge eating. For boys, the opposite was true. Few boys or girls did both, the study said.

The adolescents were also queried about teasing from their peers or negative comments from their parents, and whether they tried to look like people in the media.

For boys, their own concerns about weight and negative comments about weight from their fathers were predictors of starting to binge eat at least weekly. Girls who said their peers thought it was important to be thin and who wanted to model themselves on media images were more likely to start binge eating or purging than girls who didn't report these influences. Teasing by males was also linked to girls starting to purge.

There were two surprises: A mother's history of an eating disorder was tied to to binge eating or purging in girls under 14 but not over that age. And binge eating and purging were not as tightly linked as previously thought in girls, which means a diagnosis of bulimia that requires both behaviors may miss some teens who need help, the authors said.

"Our results suggest that prevention of disordered eating and eating disorders may need to be age- and sex-specific," the authors write. "Efforts aimed at females should contain media literacy and other approaches to make young persons less susceptible to the media images they see. Programs for females should focus more on becoming more resilient to teasing from males, whereas programs for males should focus on approaches to becoming more resilient to negative comments about weight by fathers."