Weight Suppression Is Identified as a Risk Factor for Eating Disorders

Weight suppression is associated with a higher risk for future onset of anorexia nervosa (AN), bulimia nervosa (BN), and purging disorder (PD) over a 3-year follow-up period, according to the results of a recent study. There was no correlation associated with binge eating disorder (BED).

Weight suppression was defined in this study as the difference between a person’s highest weight at their adult height and their current weight.

The researchers utilized data from 2 eating-disorder-prevention effectiveness trials. All participants were young women who had answered affirmatively when asked about body image concerns during screening. Included in the study were 1118 participants for AN, 1065 for BN, 1014 for PD, 1090 for BED, and 989 for any eating disorder.

Participants in Trial 1 were randomly assigned to either clinician-led Body Project groups or an educational brochure control condition, while those in Trial 2 were randomly assigned to clinician-led Body Project groups, peer-led project groups, an internet-delivered eBody project, or an educational video on eating disorders a control condition.

Participants in both trials completed surveys and interviews throughout the study period, starting at baseline, and again during follow-ups at months 1, 6, 12, 24, and 36 after baseline.

The Dutch Restrained Eating Scale was used to assess the frequency of dieting behaviors, the Ideal-Body Stereotype Scale was used to assess thin-ideal internalization, the Body Dissatisfaction scale was used to assess dissatisfaction with 9 body parts (such as stomach, buttocks, and upper thighs), and the Eating Disorder Diagnostic Interview (EDDI) was used to assess eating disorder symptoms. In addition, Trial 1 measured negative affect through the use of the 21-item Beck Depression Inventory. Trail 2 utilized the Positive Affect and Negative Affect Scale.

The results indicated that weight suppression predicted future onset of several eating disorders, including AN with an odds ratio of 1.36 (95% CI, 1.03-1.80), BN with an odds ratio of 1.34 (95%CI, 1.11-1.62), PD with an odds ratio of 1.46 (95% CI, 1.23-1.74), and any eating disorder with an odds ratio of 1.32 (95% CI, 1.12-1.56). However, weight suppression did not predict future BED with an odds ratio of 1.10 (95% CI, 0.89-1.37).

In addition, future onset of BN and PD were associated with highest past weight. The researchers found an inverse relationship between participants’ current weight to the future onset of AN. Despite the fact that both weight suppression and dietary restraint had increased the future risk of eating disorder onset, the two factors were uncorrelated.

“The findings have several clinical implications. First it might be useful to consider weight-suppressed individuals as a high-risk population worth targeting with selective eating disorder prevention programs. Second, results imply that individuals should be informed that losing excess weight may increase the risk of onset of eating disorders. Third, preventing initial excess weight gain should reduce the risk of future weight suppression and consequent risk of eating disorders,” the authors concluded.

—Leigh Precopio

Reference:

Stice E, Rohde P, Shaw H, Desjardins C. Weight suppression increases odds for future onset of anorexia nervosa, bulimia nervosa, and purging disorder, but not binge eating disorder. Am J Clin Nutr. 2020;112(4):941-947. doi:10.1093/ajcn/nqaa146