People who suffer from eating disorders, such as anorexia nervosa, bulimia nervosa, and binge eating disorder, are at higher risk to develop autoimmune diseases (such as ulcerative colitis and Crohn’s disease), researchers at the University of Helsinki, Finland suggest in a new study.

Noting that previous studies have suggested that autoimmune processes are involved in psychiatric disorders, the team aimed to determine the prevalence and incidence of autoimmune diseases in over 2,000 Finnish patients with eating disorders.

The study, called “The Increased Risk for Autoimmune Diseases in Patients with Eating Disorders” and published in the journal PLOS One, compared 2,342 patients who were treated at the Eating Disorder Unit of Helsinki University Central Hospital between 1995 and 2010 with general population controls. In addition, researchers analyzed data of 30 autoimmune diseases from the Hospital Discharge Register from 1969 to 2010.

Results showed that nearly 9% of patients with eating disorders had been diagnosed with one or more autoimmune diseases. This percentage dropped to 5.4% among the control individuals. Type 1 diabetes significantly contributed to the increase in endocrinological diseases, whereas Crohn’s disease was related to a higher risk of gastroenterological diseases.

Furthermore, the increased risk of autoimmune diseases among individuals with eating disorders was not exclusively due to endocrinological and gastroenterological diseases, as when these two categories were excluded, the increase was noted in patients both before the treatment of the eating disorder and at the end of the follow-up.

These findings led researchers to reinforce the link between autoimmune diseases and eating disorders. In addition, they highlight the importance of further studies to explore this connection.