Preventing Disordered Eating: A Program that Worked

Many programs designed to minimize or prevent disordered eating patterns are unsuccessful. Despite varying designs, many of these programs do not help reduce eating disorder symptoms or overweight.

According to Drs. Eric Stice and Jennifer Ragan at the University of Texas, Austin, such failures may be due to attempts to cover a large amount of psychoeducational information about eating disorders in only a few sessions and over a short time. Would a program given over a longer period make any difference in students’ attitudes and actions?

Stice and Ragan designed a semester-long controlled study of 88 undergraduate women who enrolled in a class entitled “Eating Disorders” or other upper-division seminars offered concurrently in the Department of Psychology at the University of Texas (Int J Eat Disord 2002; 31:159).

The authors included data from women only, although a few men were also in the classes. Their rationale was that eating problems are rarer in males than in females.

The intervention

The eating disorders class was described to potential participants as an evaluation of the effects of a class on students’ attitudes and behaviors. Students in other upper-division psychology seminars were approached and asked to complete parallel pretest and posttest surveys to help the researchers evaluate the effects of another course.

The authors recruited students from upper-division classes for the matched comparison group. Participants completed the 30-minute pretest in a class setting, with other students and an instructor. Because the students could not be randomly assigned to the intervention and control conditions, the control group was matched to intervention participants.

The advanced undergraduate seminar on eating disorders met for 90 minutes twice weekly for 15 weeks. Most of the sessions involved educational presentations and group discussions. The course focused on descriptions of eating disorders, epidemiology, etiology, risk factors, preventive interventions and treatments for eating disorders and obesity. Students were then required to develop a 20- to 30-minute class presentation on a topic of their choice and to write a 10-page paper on the same subject. Three written essays were also required during the semester.

During the class, the students were given a number of self-report questionnaires, including the Ideal Body Stereotype Scale, Revised, a scale that asks participants to indicate their level of agreement with statements concerning what attractive women look like (example, “Slender women are more attractive”).

Symptoms of anorexia nervosa, bulimia nervosa and binge eating disorder were assessed with the Eating Disorder Diagnostic Scale (EDDS, Stice et al, 2000). EDDS responses were used to generate threshold and subthreshold diagnoses of current anorexia nervosa, bulimia nervosa, and binge eating disorder (DSM-IV). Subthreshold diagnoses required the presence of all the symptoms of the disorder and also that at least one of these symptoms was of subdiagnostic severity, such as binge eating only once a week.

Fat consumption was assessed with an adaptation of the Fat-Related Habits Questionnaire (Kristal et al, 1999). The participants are asked to indicate how often they eat high-fat foods, using a 5-point scale from “never” to “five or more times a week.” Body mass index (BMI=kg/m2) was based on self-report data.

Results

Participants in the intervention group showed significant decreases in thin-ideal internalization from pretest to posttest, as well as decreases in body dissatisfaction, dieting, eating disorder symptoms and body mass. No decreases in these areas were shown among the matched controls.

According to the authors, the most important finding was that the intervention seemed to result in a fourfold decrease in the rate of threshold and subthreshold eating disorder diagnoses and a decrease in several risk factors for eating pathology. Another important finding was that those in the intervention group had decreased body mass (mean: 3% decrease), whereas controls had increased body mass (mean: 4% increase) over the same interval. Those with the highest initial body mass lost the most weight. Fat intake and depressive symptoms were not affected.

A ‘covert’ prevention approach

Why did this program succeed when others have failed? According to the authors, one explanation may be that the participants were not informed that they were in an eating disorder prevention program. Instead, they enrolled in what appeared to be an advanced seminar not advertised as an eating disorder prevention intervention. Could it be that individuals are less defensive about body image and disordered eating and more willing to try alternative perspectives when they are not aware they are participating in an intervention program?

An additional benefit of the so-called “covert” prevention approach is that it doesn’t require insight into eating disturbances by the participants to entice them into enrolling in the course.