The problem can resemble a traditional eating disorder or involve use of drugs and supplements, according to U.S. researchers, and it tends to go along with depression, binge drinking and recreational drugs.
Classical eating disorders include anorexia nervosa, in which a person refuses to eat, and bulimia nervosa, in which someone binge-eats then purges through vomiting or laxative use.
"For a lot of males, what they're striving for is different than females," Field said. "They're probably engaged in something different than purging."
It has been estimated that one in every 10 cases of an eating disorder occurs in men.
For the new study, Field and her colleagues used survey responses collected between 1999 and 2011 to see what concerns teenage boys had about their bodies.
Field's team also wanted to know if eating disorders were tied to later unhealthy behaviors, such as drug and alcohol use.
The surveys were answered every one to three years by 5,527 boys who were between ages 12 and 18 at the start of the study in 1999.
The researchers found that 31 percent of the teens had - at some point - binged on food or purged.
About 9 percent reported a high level of concern with their body's muscularity and about 2 percent were both concerned about muscularity and had used some type of supplement, growth hormone derivative or anabolic steroid to enhance it.
Use of those products rose to about 8 percent when the researchers looked just at 16 to 22 year olds.
"The results from this study would suggest that males who are extremely concerned about their physiques are doing or using things that may or may not be healthy," Field said.
"There are a whole range of products available online that we don't know if they're healthy or not," she said. "We know when a lot of them are tested, they're not what they're marketed to be."
Those young men who used enhancement products were also more likely than their peers to binge drink and use drugs, the researchers found.
In her mind, Field said the behavior of those young men could be the male equivalent of binge-and-purge disorders, because they're using the products to alter their bodies.
About 6 percent of the young men surveyed said that in addition to muscularity, they were also concerned about their thinness.
Overall, though, young men were more likely to be focused on muscularity and that concern increased with age.
Between 2 percent and 3 percent were concerned only about their thinness. Those young men were more likely to develop symptoms of depression later on.
"We think about a lot of disorders and diseases that look different in males than females," Field said. "This is another example and we need to remember that."
"These are not likely to be healthy behaviors," Dr. Evelyn Attia said. She is a professor of psychiatry at Columbia University Medical Center and Weill Cornell Medical College in New York.
"The overwhelming number of people - often young men - who are thinking about needing to change their body by using some of these supplements is certainly something the family should know about and we as clinicians should be aware of," Attia, who was not involved in the new study, said.
She added that those behaviors and the use of those supplements should be tracked for future research. At this point, she said, it's hard to say whether these behaviors are truly eating disorders.
Field said it would be unrealistic to expect young men and women not to be concerned about their weight or their bodies, but for some it's all they're concerned about.
"The images these teens are seeing of models don't even look like that," Field said. "They've been airbrushed and shaded â¦ so everyone believes they have unbelievable definition in their abs and arms."
The new research appeared in JAMA Pediatrics. The authors note that the survey's respondents were mostly white and middle class, which may limit the study's relevance to other populations.
Field suggested that doctors and parents should be aware of their patients' or children's attempts to change their bodies to make sure it's being done for the right reasons and in a healthy way.
"It's a good time to have that conversation," she said.
SOURCE: http://bit.ly/1b9wSIV JAMA Pediatrics, online November 4, 2013.