Ilene Fishman does not go out of her way to tell her patients about her past, but if they ask, she is honest with them: For 11 years the licensed clinical social worker, who specializes in treating eating disorders, was anorexic and bulimic herself.

"I was very, very sick," Fishman, who works in private practice in New York and New Jersey, told The Huffington Post. By the time she turned 12, her problem developed into a full-blown illness. Fishman battled the disease while coming of age in the 1970s and 80s when treatments were scant and few people saw eating disorders as a real medical problem.

Now, Fishman sees her history as an asset to her patients, giving her insights into what she called the "dark, twisty aspects of eating disorder thinking" -- insights that cannot be taught.

"It really gives me a depth of understanding," she said. "Other therapists might be less comfortable with eating disorder behaviors, but I engaged in all of them myself. I'm not intimidated by them. [And] I'm not intimidated by really low weight ... It's all familiar to me, not only in my professional experience, but personally."

Eating disorders now affect 20 million women and 10 million men in the United States. The range of treatments has expanded in the past 50 years -- there are in- and out-patient programs, multiple forms of psychotherapy and various medications -- but no one treatment has been identified as the best approach, leaving therapists and patients to muddle through together. Even less clear is what impact professionals' own battles with eating disorders have on their patients, if any.

Studies analyzing the number of eating disorder professionals who are recovered suggests that a relatively high percentage of people who enter the field have a personal history with the illness -- anywhere between 25 and 30 percent. But the topic has only started to be discussed openly in professional circles.

"Years ago, it was more secretive," Fishman said. "It was something that people didn't want to expose about themselves." The thought was that working in the field would somehow be too much for recovered professionals, who would go on to harm their patients and perhaps even fully relapse.

Dr. Beth McGilley, a clinical psychologist who works in private practice in Kansas, was one of the first in the field to "come out" publicly in the mid 1990s at one of the biggest industry conferences in the U.S. She said she did so despite being warned by several top practitioners in the field that she would be forever marginalized by her colleagues.

"I began speaking at [professional] conferences very young, and I found it was a fraudulent experience to stand in front of the audience and talk about 'them,' or people with eating disorder as though they weren't me," she said. McGilley developed an eating disorder when she was a senior in high school after her mother committed suicide. That loss and subsequent depression, coupled with a difficult transition from the progressive all-girl's school where she'd been a student for more than a decade to an image-obsessed university environment in Southern California, sparked her eating issues. Within a week of starting college, McGilley stopped going to the cafeteria altogether.

Like Fishman, McGilley dealt with her eating disorder in the 1970s and 80s, and largely figured out her own recovery. By the time she started her internship in clinical psychology with the intent of specializing in eating disorder treatment, McGilley was fully recovered, but as her career progressed, she felt wariness emanating from her colleagues.

"There was some backlash. I never overtly heard it, but friends have told me that they heard things," she said. "People have remarked about me being recovered, suspecting I wasn't."

McGilley is now co-chair of "Professionals and Recovery," a special interest group for clinicians who both treat and have been treated for eating disorders. Supported by the Academy for Eating Disorders, a major professional organization, the group has presented at several industry conferences in recent years. One of its primary goals is to help define clear expectations for what it means to be a professional who is in recovery or recovered, and whether there are markers, measured either in years or some other unit, that a person must first hit.

"When are you ready to work?" asked McGilley. "That's one of the foundational, core issues, and our field doesn't have an answer for that."

That lack of clarity is compounded by broader confusion within the eating disorder world about what "recovery" means -- or if that is even an appropriate term to use. Relapse rates are high -- some research suggests that approximately 30 percent of men and women slide back into their eating disorders after restoring their weight in treatment. "Recovery is a term that can be defined in many different ways," the National Eating Disorders Association's website states.

"Personally, I didn't start practicing until I was 'way' recovered," said Dr. Mark Warren, a clinical psychiatrist with the Cleveland Center for Eating Disorders who developed anorexia as a teenager and is co-chair of the Professionals and Recovery group. "But some people enter the field where there might be risk. If it's been two to three years, you'll want more support." That is another aim of the special interest group, to make sure practices are able to help maintain the continued recovery of therapists or other professionals as needed.

If a provider fully relapses while treating patients, the path is clear: They should no longer practice, at least until they have firmly reestablished their recovery, Warren said. The hiatus is necessary not just for the safety of patients, but also to enable the clinician to focus on his or her own needs.

"As profoundly supportive as I am of people who are recovered working in the field, you have to look at the underbelly of things," said McGilley. "There are some patients who have been harmed by therapists who aren't recovered." Some of her patients recall seeing clinicians who claimed they were healthy, but who proceeded to spend the bulk of the treatment talking about themselves.

It is unclear whose responsibility it is to monitor counselors to make sure they are not struggling, and some young therapists are "terrified" of coming out because they fear they will be penalized professionally, she said.

"By identifying yourself, you unintentionally give people permission to judge how 'recovered' you are," McGilley added.

But many leading centers publicly embrace recovered professionals, among them, the Emily Program, which states on its website that it employs recovered individuals. So does the Monte Nido group, which has outposts across the country.

"I have hired many, many [recovered professionals] over the years and am known for that," said Carolyn Costin, Monte Nido's founder and a former anorexic. She has established her own guidelines for what she feels makes her counselors sufficiently ready to practice. "I never hire anyone unless they have two years of being what I call recovered. No symptoms, no thoughts, not dealing with it one day at a time, or in therapy for their eating disorder," Costin said.

Ultimately, like Fishman, she views a personal history with eating disorders as a "huge asset," saying it is one of the reasons why many of her clients seek out her practice. Her patients have likened seeing a therapist who has never had an eating disorder to going skydiving with someone who had never done it before.

"Some patients have said that it is the most critical factor in their successful recovery," said Costin. "I never really expected that."

But experts say there is a long way to go before such acceptance infiltrates the entire eating disorder field and before clear expectations for what it means to be recovered and how the topic is best worked into practice have been codified.

"The discussions have actually begun, which is exciting," Warren said. "It has moved into the realm of a very reasonable thing to be talked about by serious people."

Correction: An earlier version of this story incorrectly stated that Warren is a clinical psychologist. He is a clinical psychiatrist.