The number of men suffering from eating disorders is rising, says the Royal College of General Practitioners.
It says it wants doctors to be more aware of the problem because it is usually seen as a female issue.
"If doctors see a young man who is thin they are more likely to think that he is depressed," a spokesperson said.
The NHS says there's been a 66% increase in hospital admissions in England for male eating disorders over the last 10 years.
The charity beat estimates that 1.6 million people in the UK have an eating disorder and it is thought that one in five sufferers is male.
The Department of Health does not keep records which show exactly how many sufferers there are in England.
It only keeps records of hospital admissions, so it can be hard to judge the scale of the problem.
That could be down to the diagnosis methods, which are predominantly based around females, an approach the Royal College of General Practitioners also stresses needs change.
GP Claire Gerada says that the rise in male eating disorders is because image has become more of an issue.
"Men are much more aware of their bodies, they are much more into dieting and how they look," she said.
She is also concerned that these issues can develop for young men while they are at university.
Ben Porter, 20, from Kent, has suffered with anorexia and bulimia since the age of 14.
"I had the usual anxieties about body image," he said.
"I just felt very inadequate about the way that I looked and felt I wasn't fitting in at school."
When he finally went to his GP, he said he felt they were only concerned with the physical health issues rather than the psychological aspect of his disease.
Ben, who is 5ft 10in (1.8m), said things became serious when he went down to 98 pounds.
He said: "I fell in to a cycle that continued until it became unbearable for everybody.
"I didn't realise what I was doing to myself and was abusive to my body at the time. The point was to look good and pursue a perfect image but I was doing the opposite."
Ben was put on an NHS waiting list but when his situation became desperate, he went for private treatment.
He is now showing signs of improvement and has reached one of his targets, which is to eat chips for the first time in five years.
Ben says he would like schools to address the issue and for them to teach body confidence to boys as well as girls.
"Male anorexia and male eating disorders are a severe problem and it needs to be addressed as not just being a female disorder but something that can affect anybody," he said.