New Study Sheds Light on Genetic Causes of Anorexia
New research sheds light on what causes anorexia and upends popular understanding of it as an eating disorder caused by low self-confidence and poor body image. Researchers have identified a potential metabolic root cause to the eating disorder, as well as a psychiatric one.
Anorexia nervosa is an eating disorder characterised by low weight, fear of gaining weight, valuing thinness, and self-imposed restriction on food intake. It’s a complex condition often triggered by both environmental and genetic factors. Researchers led by Cynthia Bulik, PhD, FAED, founding director of the UNC Center of Excellence for Eating Disorders and a professor at Karolinska Institutet in Stockholm, Sweden, looked into the later, undertaking the most significant investigation of the genetic causes of anorexia to date. They compared DNA from 3,495 individuals with anorexia with DNA from 10,982 unaffected people and found distinct variations that point to two genomic regions from where the disorder originates.
One of these regions is also associated with psychiatric conditions like neuroticism and schizophrenia, but “unexpectedly, we also found strong genetic correlations with various metabolic features including body composition (BMI) and insulin-glucose metabolism,” Bulik explained.
This pinpointing could help develop better treatments that target the underlying biological causes of anorexia, rather than manage the eating disorder’s symptoms.
In India, anorexia is relatively rare, though it is difficult — if not impossible — to determine its prevalence with any precision because data is lacking. But even if incidence is low, that doesn’t mean the genetic risk isn’t there – it may just be that the trigger is missing:
“One possibility is that ‘genes load the gun, and environment pulls the trigger,’” Bulik said. “It might just be that the environment in India has not yet gotten to the point where there is as much dieting (for example) which can often be the trigger for individuals at risk for anorexia nervosa.”
East or West, however, researchers hope their findings put to rest the traditional (mis)understanding of what influences eating disorders, which often get written off as the crazed and unhealthy obsession of Insta-influenced teens.
“It is time to erase those old myths and replace them with science-derived facts,” Bulik said. “Anorexia nervosa is clearly influenced by genetic factors and those factors are both psychiatric and metabolic. In fact, in Asia, we often see anorexia in the absense of body dissatisfaction. These myths are just the cultural packaging we wrap around anorexia.”