NEW YORK (Reuters Health) - The most important factor in the successful treatment of eating disorders is improving the patients' perception of their body -- and that's not an easy task, says a psychologist with the Eating Disorders Program at The Menninger Clinic in Houston.

"It's very difficult to do because we live in an anorexic culture where the thin ideal is all we see in the media and people basically have to challenge that definition of beauty in order to recover," said Dr. Theresa Fassihi. "In research, we've found that body image issues are the last thing to change when we are treating people with eating disorders."

If people complete an eating disorders treatment program but still harbor negative body image thoughts and feelings, "they will have a hard time not reverting to their old eating disorder behaviors," Fassihi told Reuters Health.

Fassihi and mental health counselor Deborah Henderson designed a 12-week course that focuses on helping people with eating disorders improve their body image. Their program, which combines cognitive-behavioral therapy and "experiential" therapy, is based on the work of Dr. Christopher Fairburn, a psychiatrist and eating disorders expert at the University of Oxford, England.

A key part of the program is taking a body image history, which allows patients to figure out how they came to have body image issues. "Typically, what patients find is that when they were very young, before they started school, they didn't worry about how they looked. They often remember how free they felt before they became focused on their body," Fassihi explained.

"As they progress through their history, they may remember getting thin messages from the media, comments from parents and friends about their body, or they may remember getting teased at school about being chubby," Fassihi said. As a result, they get sensitized to their body and develop distorted thoughts about how they look.

The cognitive-behavioral piece of the program addresses thought-distortion in eating disorders. In one exercise, for example, patients are asked to estimate how much string it would take to wrap around their thigh, waist or other body part they are concerned about.

Patients often think the amount they would need is three times more than what it actually takes. When they measure the actual circumference of their thigh or waist, they realize it is much smaller than imagined, Fassihi noted.

Patients also participate in a body image party, where they are instructed to come up with a word that describes their body. A woman may say she's fat. The group then gives her the feedback that that is not the way they see her. This helps the woman see how the world really views her. During body image parties, patients are also challenged to come up with positive words to describe their body.

In experiential group therapy, patients draw on paper what they think they look like. Then they help each other actually trace the outlines of their bodies onto paper. Often patients overestimate the size of their bodies. Seeing the difference between the two drawings can be very enlightening, Fassihi said.