Genetic links between eating disorder symptoms and suicidal ideation

An MQ researcher has found a shared genetic susceptibility between eating disorders and suicidal ideation. 

(Please note, this blog mentions suicidal ideation throughout.)

Eating disorders such as anorexia nervosa, bulimia nervosa, and binge eating disorder are more than just struggles with food and body image. They carry serious medical and psychological risks. Among these risks, mortality, especially suicide, stands out. Eating disorders have some of the highest mortality rates among psychiatric conditions, with a significant portion of deaths attributed to suicide. But why do these conditions and suicidal ideation so often go hand in hand?

A  recent MQ funded study from Dr Moritz Herle at the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London and the National Institute for Health and Care Research (NIHR) Maudsley Biomedical Research Centre sheds light on this important research topic.

Using data from around 20,000 participants in the NIHR Mental Health BioResource COVID-19 Psychiatry and Neurological Genetics, Moritz and his team explored the genetic overlap between eating disorder symptoms and suicidal ideation. Their findings move us closer to understanding how shared biological factors contribute to both.

 

What we know already

Years of twin and family studies convey to us that both eating disorders and suicidality have a strong genetic component. Eating disorders are highly heritable – genetic factors significantly influence who develops anorexia nervosa, bulimia nervosa, or binge eating disorder. Suicidal ideation and behaviours also have a genetic basis, affecting thoughts of self-harm, suicide attempts, and completed suicide. Yet, while genes play a role in each condition, less is understood about the shared genetic impacts that might drive vulnerability to both.

 

A new approach

Unlike traditional genetic studies that focus on a single diagnosis, this study took a broader, multivariate approach by examining symptoms of anorexia nervosa, bulimia nervosa, or binge eating disorder, rather than just diagnosed cases. Moritz and his team also focused on suicidal ideation, including thoughts and feelings related to self-harm or ending one’s life.

The main findings suggest a shared genetic susceptibility which can partially explain the overlap between eating disorders and suicidal ideation. However, there were also separate genetic influences unique to each. Genetic factors explained 9% of how individuals differ in their susceptibility to eating disorders and suicidal ideation.

 

Why this matters

These findings suggest that certain genetic profiles may increase vulnerability to both disordered eating and suicidal thoughts.

This doesn’t mean that someone with an eating disorder will necessarily experience suicidality, but it highlights a measurable, underlying biological connection.

Many people assume suicidality in eating disorders is primarily due to co-occurring depression or anxiety. While mood disorders do play a role, this study found that even after accounting for depression and anxiety, the genetic link between eating disorders and suicidal ideation remained. This suggests a distinct, inherent relationship between the two.

 

The bigger picture: Clinical and personal implications

In the clinical context, our findings suggest that mental health professionals should routinely screen for suicidality in patients with any disordered eating symptoms, even if they aren’t showing symptoms of mood disorders. Treatments need to address the unique interplay between eating disorders and suicidal thoughts, rather than focusing solely on depression or anxiety. For individuals struggling with an eating disorder, understanding that suicidality may have a genetic root can be validating. It stresses that these thoughts aren’t simply a choice or a byproduct of another condition but may be deeply tied to the disorder itself.

 

What’s next for research?

Future research needs to include longitudinal datasets to understand how these conditions progress. This can help clarify whether one precedes the other, informing better prevention strategies. We also need more diverse samples to guarantee that findings apply more broadly, as most participants in this study were of European background. Importantly, recognising shared genetic variants is just the first step. The main challenge now is interpreting this knowledge into interventions that can decrease risk and improve outcomes.

 

This work is supported by Rosetrees, Bird Song Trust and the Stoneygate Trust. This blog was written by Agnieszka Musial.

 

If you have been affected by an eating disorder, suicidal thoughts or if you need to talk, help is available. Please visit our Get Help page for a list of organisations who are there for you.