Traditionally, eating disorders have been regarded chiefly as a mental health issue tied to body weight and appearance. However, mounting evidence points toward multifactorial origins. In this context, a recent study involving researchers from the Karolinska Institute (Sweden) and King’s College London (United Kingdom), in collaboration with an international panel of experts, has identified genetic variations linked to an increased risk of developing such a condition.
The study, published in Nature Mental Health, aimed to analyze the genetic factors that might influence these health problems and was conducted by comparing DNA—the molecule that contains the organism’s genetic information and helps determine how it functions—between people with eating disorders and those without such conditions. Specifically, nearly 40,000 individuals suffered from binge eating disorder and about 25,000 from anorexia nervosa, compared with more than 1.2 million people with no diagnosed eating-behavior disturbance.
As a result, researchers observed six regions in the genome —concrete regions of DNA, also known as genetic loci— linked to binge eating and eight associated with anorexia nervosa. Of these latter eight, two had not been identified previously, while the other six loci had already been implicated in a 2019 genetic study of anorexia, further reinforcing the evidence of their role in this condition. In line with this, some regions of the genome associated with episodes of excessive eating had already been connected to body-size traits, such as the FTO gene, related to body weight.
«This research confirms at the genetic level that eating disorders are not solely about body weight; many of the gene variants linked to these conditions differ from the variants of the genes linked to an individual’s weight,» says Dr. Helena Davies, the study’s co-lead author, in statements cited by News Medical. «In the long term, this knowledge could help develop more targeted treatment strategies that take into account the particular characteristics of each condition,» notes Professor Lisa Dinkler, who also contributed to the development of this research, according to Euronews.
Biological Link to Other Conditions
Finally, the study showed that these two manifestations of eating disorders share part of their genetic underpinnings with other traits and behaviors. The binge-eating pattern demonstrated genetic associations with smoking, a tendency to take risks, and attention-deficit/hyperactivity disorder (ADHD), while anorexia nervosa showed a stronger genetic link with obsessive-compulsive disorder (OCD). The researchers also noted that, although there are connections between the genetic factors linked to these health problems and body mass index (BMI), most of the genetic signal related to both binge eating and anorexia nervosa cannot be explained by BMI.
Eating Disorders
Eating disorders can manifest in diverse ways, from food restriction to episodes of binge eating. Yet their effects go far beyond eating habits and can have serious consequences for both mental and physical health, in addition to disrupting daily life. There are several types of eating disorders, including anorexia nervosa, bulimia nervosa, and binge-eating disorder.
Among them, the study focused on individuals with anorexia nervosa—a eating disorder characterized by restricted food intake, an intense fear of gaining weight, and excessive concern about weight and body image—and on binge-eating behavior, a pattern that can appear in various forms of these conditions and consists of episodes where a person consumes an unusually large amount of food in a short period and feels unable to control what they are eating.
