More RelationTIPS Ask columnist Dennie Hughes your question RelationTIPS chat every Monday at 4 p.m. ET

The Usher effect?

Pressure to be buff is fueling a growing problem: bulimic boys.

Kim Hanson had no idea that her 15-year-old was caught in the throes of an eating disorder when her younger daughter first told her she was worried. After all, the teenager was her son, and "boys don't get eating disorders!" says the Stillwater, Minn., mother. "But then we saw him without his shirt. He was so thin it was shocking."

Eating disorders, long considered a "girl problem," have been increasing among boys at an alarming pace, says Leigh Cohn, co-author of "Making Weight: Men's Conflicts with Food, Weight, Shape & Appearance." He points to the two most recent studies, which show the rate among young men is at least three times what had been considered the status quo, or up to 2% of young men. (By comparison, the rate among young women is about 4.5%.) Anorexics lose weight by starving themselves; bulimics binge eat and then purge their food.

Ted Weltzin, director of the eating disorder clinic at Rogers Memorial in Oconomowoc, Wis., says he is disturbed by the jump in the number of boys he treats. In 2001, he had 14 young male patients. In 2005, he had 33.

The culprit? "The rise of unrealistic male body images being presented in the media and Madison Avenue are having a profound effect on men, especially young men, who already are uncomfortable with the changes their bodies are going through," Weltzin says. Ripped stars like Usher, six-pack models in popular teen clothing catalogs and pro athletes on steroids send the message that women have had to deal with for years: having a perfect, toned body brings adulation and success.

Nathan Hanson, whose weight plunged from 150 to just 112 pounds on his 5-foot-9 frame, understands these influences all too well. He says his attempts to lose weight started in eighth grade, after years of others picking on his body. "All the conversations centered on girls, and everyone seemed to accept people based on who was hot," says Nathan, now 18 and a college freshman. "Even the guys talked about working out, losing weight -- not to get healthy, but to get skinny, because skinny equals having a great life."

Weltzin urges parents to look for warning signals. Stay alert to any mention of being called names or an obsession with appearance. Guys are prone to overexercising and purging or laxative use, rather than starving. Notice how often he's in the bathroom, especially after meals or working out.

Having relapsed once before, Nathan says he knows how easy falling back into old habits can be. But for now, he feels confident about his future. He has a medically structured meal plan and a new attitude about what's important. "Don't compliment what I look like," he says, "but what I'm accomplishing."