New genetic research led by King’s College London reveals that binge eating and anorexia nervosa possess distinct genetic associations separate from body mass index. Published in Nature Mental Health, the study analyzed DNA from nearly 40,000 individuals with binge eating and 25,000 people with anorexia nervosa, identifying unique genomic loci.
A landmark global study published in Nature Mental Health shifts that paradigm by demonstrating that the genetic architecture of eating disorders operates independently from the genes governing overall body size.
Uncovering Genomic Loci for Binge Eating and Anorexia Nervosa
Led by the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London alongside an international research partnership, the team conducted the largest ever genetic study of anorexia nervosa while simultaneously comparing the genetics of people with binge eating against unaffected individuals for the first time.
Researchers examined DNA from roughly 25,000 people with anorexia nervosa and nearly 40,000 individuals exhibiting binge eating. They contrasted these genetic profiles against more than 1.2 million unaffected people across 27 global datasets. The analysis uncovered six genomic areas, or loci, associated with binge eating and eight loci linked to anorexia nervosa among individuals of European ancestry. Among the anorexia nervosa loci, six had previously appeared in a 2019 genetic study, reinforcing their biological relevance, while two loci were identified for the very first time.
Separating Eating Disorders from Body Mass Index
A critical takeaway from the findings is that genetic associations tied to binge eating and anorexia nervosa do not mirror those connected to body mass index (BMI), even though body mass index remains a clinically important factor in both conditions. Investigators emphasize that the biological pathways driving these disorders involve distinct genetic variants.
“This research confirms on a genetic level that eating disorders are not just about body weight; many of the versions of genes linked to these conditions are different from the versions of genes that are linked to how much someone weighs.”
Dr Helena Davies, postdoctoral research fellow at the IoPPN and joint-first author on the study
Interestingly, some of the newly identified binge-eating loci intersect with known body size traits. One such locus sits near FTO, a well-known gene long studied for its ties to higher body weight. Researchers suggest that binge eating may partially help explain the established biological connection between FTO and higher BMI.
Broadening the Scope Beyond a Single Diagnosis
Binge eating acts as a symptom cutting across multiple conditions, including binge-eating disorder, bulimia nervosa, and select presentations of anorexia nervosa. By isolating the genetic signature of the symptom itself rather than relying solely on rigid diagnostic boundaries, the study offers a clearer view of shared psychiatric biology.
Senior leaders on the project emphasize that understanding binge eating marks a vital expansion in eating disorder research.
“We’ve been making important progress in understanding the genetics of anorexia nervosa for several years, but that’s only one of several eating disorders that have major impacts on people’s lives. This work is really important – we go beyond anorexia nervosa and start to understand the genetics of binge eating, which affects many people with eating disorders. We’re hopeful that our findings will allow future research to improve the lives of people with all eating disorders.”
Dr Jonathan Coleman, Senior Lecturer in Statistical Genetics at King’s IoPPN and lead senior author on the study
Global Consortium and Future Directions
The published findings stem from the Eating Disorders Working Group of the Psychiatric Genomics Consortium, an international collective focusing on mega-analyses of psychiatric and eating disorder genetics. Financial backing for this phase of the work came partly from the Health">US National Institute for Health (Health">NIH), alongside support from bodies like the Health and Care Research">NIHR Biomedical Research Centre at Maudsley.
With this foundation established, the research team is already looking ahead. Their next steps involve expanding genetic analyses to encompass atypical presentations and Avoidant/Restrictive Food Intake Disorder (ARFID). Investigators also plan to incorporate broader global ancestries to ensure future discoveries yield universal clinical relevance for patients worldwide.
