A little-known form of the eating disorder bulimia is getting more and more attention from medical professionals -- exercise bulimia.
As CBSNews.com's Cali Carlin reported on "The Early Show Saturday Edition," people with the disorder can't stop themselves from working out excessively and compulsively, with potentially serious health consequences.
This "startling" form of bulimia is of particular concern, Carlin says, because it happens in plain sight and doesn't involve the hidden vomiting-to-purge-calories marking the form of bulimia more people are familiar with, making exercise bulimia hard to recognize, and insidious.
In addition, she points out, eating disorders in general have the highest mortality rate of any mental illness.
Carlin spoke with Robyn Yamanaka who is, ironically, a professional trainer.
Yamanaka told Carlin her exercise bulimia "started off innocently, (with workouts) maybe like three or four times a week. ... (But) it got to a point where I was working out three hours a day, if not more. ... I didn't take a day off for about 6 years. ... I have more health problems than someone who is overweight because I was underweight."
Dr. Maryanne Rosenthal, clinical director at Casa Palmera, an in-patient treatment center in San Diego says, "I think(exercise bulimia) is becoming epidemic. ... An exercise bulimic is focused on the ritual of exercising, and that is that method of purging.... People think they get a pass because they're not vomiting, they're not taking laxatives, so (they think) they're not really purging. ... It's very hard to diagnose, because exercise is great right?"
Health woes spurred by exercise bulimia can include fatigue,reproductive problems, depression and anxiety, Rosenthal observes.
Yamanaka, says Carlin, was "exercising herself to death. Her bones had weakened to the equivalent of a 65-year-old female. She suffered from osteoporosis, a stress fracture and lost her period for eight years."
Rosenthal calls exercise bulimia "an addiction and, when people are really heavily into their addictions, they can't stop without help."
Yamanaka tearfully told Carlin that her parents forced her to get treatment, and says she's recovering and even back on the job.
"Im really lucky," she observes.
Best-selling author and dieting expert Dr. Ian Smith told "Early Show Saturday Edition" co-anchor Erica Hill signs someone you know may be an exercise bulimic include that person missing work, parties or other important appointments to work out, not taking a break from working out for days at a time, working out for hours at a time each day, working out while injured or sick, or becoming severely depressed when not being able to work out.
Smith, who's also the medical and diet expert on VH1's highly-rated "Celebrity Fit Club," said to CBS News you should approach someone you're concerned about with caution: "Discuss with them the amount of time they're spending on working out relative to where they are with the goals they want to achieve from working out. Most of these people are already low in fat and within the healthy weight range. Try to bring it to their attention that they have had great success and results from working out. The quantity of time they're spending is out of proportion to what they need to maintain their results. Suggest they see a therapist who can help them sort out what's going on.
"Softly discuss what they may be neglecting so that they can work out. Try to get them to see that they are allowing exercise to disproportionately occupy time and space in their life. Maybe they are suffering some of the consequences of exercising too much (fatigue, dehydration, osteoporosis, arthritis, reproductive problems, injuries such as stress fractures, strains, and sprains), and pointing these consequences out may help them see what they're doing."
Smith noted that, "Unlike (with) classic bulimia, exercise bulimia is almost just as common in men as it is in women. Exercise bulimia is not about the person wanting to improve their health or train for a specific event. They exercise for the sake of exercise."
If someone resists getting help or receiving consul, Smith said, "There's not much you can do, unless they are a minor. This is not a condition where you can commit someone to a psychiatric clinic or make them go get help. The best thing to do at that point is to be as supportive as possible and encourage rather than mandate they seek at least some counsel."
, who's also the medical and diet expert on VH1's highly-rated "Celebrity Fit Club,"