A landmark global study including University of North Carolina eating disorder expert Cynthia Bulik, Ph.D., FAED, has, for the first time, mapped and compared the genetic profiles of binge eating and anorexia nervosa. The research finds that although the two conditions share some genetic features, they also differ in important ways.
The study now published in Nature Mental Health confirms that eating disorders are driven by a mix of psychiatric and metabolic genetic factors and points to the need for more tailored, biology-based treatments.
"Even though these two conditions both fall under the category of eating disorders, they clearly differ deeply on a biological level," explained Bulik, a distinguished professor in the Department of Psychiatry at UNC School of Medicine and founding director of the UNC Center of Excellence for Eating Disorders.
By analyzing DNA from tens of thousands of people worldwide with binge eating or anorexia nervosa, the team identified clear genetic signatures for each condition:
- For the first time, the researchers identified six specific regions of the genome associated with binge eating, one near a famous gene linked to obesity (FTO).
- They also identified eight different regions associated with anorexia nervosa.
- Both anorexia nervosa and binge eating shared genes linked to other psychiatric disorders, like depression and anxiety.
- Anorexia nervosa was more strongly linked genetically to obsessive-compulsive disorder, whereas binge eating was more strongly linked to ADHD.
- Both conditions had strong genetic links to body weight, but in opposite directions. Genes that contribute to higher body weight also contribute to binge eating, whereas they decrease the chance of you developing anorexia nervosa
Previously, eating disorders were thought to be completely psychological illnesses. These findings rewrite the book and show that both binge eating and anorexia nervosa are "metabo-psychiatric" conditions that are influenced by both psychiatric and metabolic genetic factors, although some effects are in opposite directions.
"These results not only help us understand both shared and distinct causes of these eating-related traits but may also help us develop more precise treatments targeting the specific biology of each condition," said Bulik. "Clearly a one-size-fits-all approach to treating all eating disorders is not the way to go."
The team is now expanding its work to include other eating disorders, such as avoidant/restrictive food intake disorder, or ARFID and atypical anorexia nervosa (AAN). The researchers are inviting people with all eating disorders to take part in genetic studies. Anyone interested in participating can visit the Eating Disorders Genetics Initiative 2 (EDGI2) website at edgi2.org.
"We won't stop until we have completed the genetic library of all eating disorders," Bulik said. "We must improve our understanding of the biology underlying these illnesses so we can improve outcomes and save lives."
The full study is published in Nature Mental Health and can be found here: https://www.nature.com/articles/s44220-026-00698-2.
