Over-the-counter diet pills are not regulated by the Food and Drug Administration (FDA), which means using them does not not require a health care provider’s guidance or prescription. 

A new study from School of Public Health (SPH) researchers investigated how likely people using diet pills and laxatives are to be diagnosed with an eating disorder in the future. The study results showing their risk of being diagnosed increased significantly were recently published in the International Journal of Eating Disorders.

“Living in a society that places a strong emphasis on thinness, which goes well beyond any health benefits, can place people at risk for engaging in concerning behaviors such as the use of diet pills and laxatives for weight control purposes, and also for the development of serious eating disorders,” says study co-author and Professor Dianne Neumark-Sztainer.

The researchers analyzed data from 1,015 females without a prior eating disorder diagnosis who participated in the Project EAT (Eating and Activity in Teens and Young Adults) study. These participants were followed from adolescence into young adulthood over a 10-year period. During that period, the girls and young women were surveyed about their health and behavior, including their use of diet pills and laxatives as well as receiving a diagnosis of having an eating disorder. 

The study analyzed the risk of receiving an eating disorder diagnosis within five years for people who did and did not use diet pills and laxatives. 

The study found:

• Participants who reported using diet pills had 258% greater risk of being diagnosed with an eating disorder compared to those who did not.
• Those who used laxatives to control their weight had 177% greater risk of receiving an eating disorder diagnosis compared to those who did not.

“These findings suggest that using diet pills and laxatives to control weight does seem to predict future diagnosis of an eating disorder,” says study lead Vivienne Hazzard, an incoming postdoctoral fellow at SPH, who completed the research while at the Sanford Center for Biobehavioral Research.

“The longitudinal nature of this study, over a 10-year period, allows for the assessment of temporality, meaning that the use of diet pills and laxatives preceded the onset of an eating disorder,” says Neumark-Sztainer. “This could either mean that use of these products is an early marker of an eating disorder, or that these products actually serve as risk factors for eating disorders. If using these products does increase risk for an eating disorder, it could be by contributing to dysregulation of eating behaviors and/or digestion.” 

The researchers said the study results emphasize how critically we need policies to reduce access to these products, such as the bills that are currently being considered in California (AB-1341), New York (S16A/A431A), and Massachusetts (H.2331/S.1525) to ban the sale of over-the-counter diet pills to minors.

Hazzard noted that the study only looked at females and future research is needed to examine whether using diet pills and laxatives to control weight also predicts future diagnosis of an eating disorder among males.