People with anorexia nervosa have unusually high levels of a hormone called LEAP2 in their blood when they are in the acute phase of the disorder, according to research presented at the Federation of European Neuroscience Societies Forum 2026. Patients with the highest levels of LEAP2 are more likely to relapse following treatment for anorexia nervosa.
The research suggests that levels of this hormone are linked to impulse control, which could be a factor in avoiding food in anorexia nervosa or emotional eating in patients with binge eating and purging behaviors. The researchers also found that LEAP2 appears connected to blood sugar regulation and an abnormal tolerance for being underfed, which may help explain why patients can restrict their eating for extended periods.
Dr. Virginie Tolle, a neuroscientist at INSERM working at the Institute of Psychiatry and Neuroscience of Paris, France, presented the findings. She said, "Anorexia nervosa is a complex disorder predominantly affecting young women. It is characterised by self-imposed food restriction, often accompanied by hyperactivity, which together can lead to severe undernutrition and potentially life-threatening consequences. Indeed, anorexia nervosa has the highest mortality rate amongst all psychiatric disorders." Tolle added that despite its severity there is currently no effective drug treatment; existing treatments rely on nutritional rehabilitation and multidisciplinary care, but recovery can take months and relapse rates remain high.
The study included 30 women aged between 18 and 60 years diagnosed with anorexia nervosa who underwent a four-month refeeding program at Sainte-Anne Hospital in Paris. Blood samples were collected before treatment, after treatment, and six months later; participants also completed detailed behavioral questionnaires. The researchers discovered that patients had 20% higher levels of LEAP2 when first hospitalized compared to after four months of hospital treatment—a difference particularly notable among those who relapsed six months after discharge.
Animal studies supported these findings: mice subjected to restricted feeding displayed increased impulsivity associated with higher LEAP2 levels during refeeding periods. Dr. Tolle said, "Our findings suggest that metabolic signals that normally regulate hunger adapt differently in pathological eating such as anorexia nervosa. These signals also influence the brain and decision-making processes." She continued, "What we have learned about LEAP2 suggest it is a potential target for much-needed new therapeutic strategies...our research identifies LEAP2 as a biomarker of relapse...it could be possible to test and monitor patients and adapt treatment as needed."
Professor Christina Dalla from National and Kapodistrian University of Athens commented on the research: "Anorexia nervosa is a highly complex disorder influenced by many biological, psychological, and environmental factors...by combining data on patients with mouse studies, the researchers have been able to learn more about the biological mechanisms underlying anorexia nervosa." Dalla said this work helps explain how changes in metabolism may affect brain reward systems influencing eating behavior.
