Adolescent Thinness Expectations Mediate Risk for Extreme Weight Control Behaviors

Thinness expectancies appear to mediate the influence of binge eating and depressive symptoms on the risk for engaging in weight control (WC) behaviors in adolescents, according to a study published in the International Journal of Eating Disorders.

Eating disorders in both boys and girls are known to emerge during adolescence. Weight control behaviors such as compensatory exercise, fasting, self-induced vomiting, and use of laxatives and diuretics are associated with adverse effects in this population, including internalization of the thin ideal, psychosocial impairment, depression, and suicidality. Three risk factors have been identified for the development of WC behaviors — binge eating, thinness expectancies, and depression — but their interrelationships and ability to predict risk in youth have not been established.

Anna Marie L. Ortiz, MS, of the University of Kentucky, Lexington, and colleagues used data from 1758 adolescents from a large longitudinal study that followed youth in 2 Kentucky counties from 5th grade through 10th grade to explore the interrelationship of these factors. Binge eating, depressive symptoms, thinness expectancies, and WC behaviors were assessed in participants in 8th, 9th, and 10th grade. The investigators tested 6 different possible transactional processes using mediation tests as well as the effect of gender on results.

Investigators noted that although both binge eating and depression in 8th grade predicted 10th grade WC behaviors through their influence on thinness expectancies in 9th grade, 8th grade thinness expectancies did not appear to predict 9th grade depression and 10th grade WC behaviors. Furthermore, no interactions among the 3 variables predicted WC, nor did gender affect these results.

Researchers assert that these results add to the understanding of risk and suggest potential intervention pathways for clinicians. They note, however, that the results are limited by the self-reported nature of the data and the lack of objective data on body mass index and depressive symptoms.

Reference

Ortiz AML, Davis HA, Smith GT. Transactions among thinness expectancies, depression, and binge eating in the prediction of adolescent weight control behaviors [published online January 9, 2019]. Int J Eat Disorder. doi: 10.1002/eat.23001