The Microbiome’s Influence on Binge-Type Eating Disorders

Cynthia M. Bulik, Ph.D., FAED, holds the first endowed professorship in eating disorders in the United States and is the Founding Director of the UNC Center of Excellence for Eating Disorders. She founded and led the 18-country Genetic Consortium for Anorexia Nervosa and is the lead Principal Investigator of the four-nation Anorexia Nervosa Genetics Initiative (ANGI). Additionally, she is the Director of the first NIMH-sponsored Post-Doctoral Training Program in Eating Disorders. Dr. Bulik has received numerous awards in her field, and has written 7 books, as well as over 590 scientific papers and chapters, on eating disorders.

The Microbiome’s Influence on Binge-Type Eating Disorders

Our team at the University of North Carolina at Chapel Hill pioneered the investigation of intestinal microbiota in eating disorders. In our early studies of individuals with anorexia nervosa, we identified an imbalance in their intestinal microbiota and an association between their intestinal microbiota, anxiety, and depression.

Though we were able to expand our understanding of anorexia nervosa, most genomic and microbiome research on eating disorders, until now, has focused on this singular eating disorder. As a result, we know almost nothing about the molecular genetic basis of or role that enteric microbiota play in the causes, persistence, recovery, and relapse of binge-type eating disorders. To fill this gap, our team recently expanded our research to study individuals with bulimia nervosa and binge-eating disorder.

We already know that people with eating disorders often have gastrointestinal problems that persist even after they have recovered from their eating disorder. Given the established relationship between the complex community in our intestines and weight regulation, it is possible that enteric microbial communities can influence binge-type eating disorders. Moreover, the cumulative genes of a microbiome vary in composition and diversity across different body habitats and may influence disease. Our understanding is that binge-type eating disorders offer model conditions in which to study interactions between host genomic variation and the human microbiome.

Thanks to our partnership with uBiome, we can accelerate the pace and scope of our research. uBiome granted 500 Five Site Explorer™ kits to the first phase of this research, in which we collected nose, mouth, skin, gut, and vaginal microbiome samples from participants. In the second phase of our study, we will collect another 500 gut microbiome samples.

Study participants are using an application—Recovery Record— adapted for the Apple Watch to log their current eating disorder symptoms (such as binge-eating and compensatory behaviors), gastroenterological symptoms, and anxiety and depression levels. Via the Apple Watch, we are simultaneously collecting a wealth of passive data on their sleep, heart rate, and physical activity, among other information. This investigation is unprecedented in its scope, and will, for the first time, enable bulimia nervosa and binge-eating disorders to be studied with modern genomic and microbiome approaches.

Our goal is to determine if there are any characteristic changes in the gut bacteria in individuals with binge-type eating disorders that may serve to maintain eating disorder behavior and whether changes in bacteria could signal recovery or risk of relapse. We also hope to improve the psychological and physical experience of patients undergoing treatment. Ultimately, by applying genomic and microbiome data, we aim to improve both the efficacy and acceptability of interventions for binge-type eating disorders, and develop more tailored approaches to treatment.