Are Eating Disorders Hereditary? Is There a Genetic Link?

Are eating disorders hereditary? What is the connection between eating disorders and heredity? Are some people more genetically predisposed to these illnesses than others? Sure, psychosocial factors—such as environmental influence and media exposure—can lead to disordered eating behaviors, but what about the biological piece? It strikes me as curious that my mother, grandmother, and great-grandmother all exhibited tendencies around both food and body image that I know to be consistent with eating disorders. And moreover, I cannot help but wonder if there is a genetic link between these patterns of generational dysfunction and my own battle with anorexia. So this curiosity has prompted me to delve into what science might reveal in terms of eating disorders and heredity.

What Research Has Found About Hereditary Eating Disorders

In 2012, clinicians at Michigan State University studied a group of 300 female twins, ages 12–24, who shared the same genetic code. Their objective was to determine how many of these subjects internalized a "thin ideal" as their desired physique. Based on how each set of twins ranked their preference for thinness, these researchers were able to conclude that over 40% of participants had a genetic predisposition to thin idealization.¹ In fact, this hereditary component was noted to cause disordered eating behaviors at a higher rate than social, cultural, or environmental impacts. 

Another study conducted at the University of North Carolina found a correlation between the formation of anorexia and genetic anomalies in chromosome 12. These scientists examined the genetic material of 3,500 adolescents across the globe who had been diagnosed with anorexia and observed that many people in this group had some degree of mutation in their chromosome 12.² This further implicates heredity as a potential risk factor in the development of eating disorders.  

Why Considering Heredity Can Help in Eating Disorder Recovery

While it is possible that my genetic code and family of origin contributed to the earliest symptoms of my eating disorder, just like any mental illness, this issue is complex and can trace its roots to a number of sources. For example, as a teenager, I was bullied for my appearance which resulted in a distorted body image and a restrictive mindset toward food. Of course, I was also not immune to the media's standard of female beauty, and I consumed all sorts of messages—both on TV and in print—that "skinny" equals attractive, desirable, and successful.         

But the question still remains, would I have been less susceptible to internalizing harmful body perceptions if there was no generational pattern of this in my own family? I cannot answer that with absolute certainty, but I do know that taking into account the possible connection between eating disorders and heredity has created a framework to better understand why I am more vulnerable to body image-centric triggers than some other people are. It has enabled me to feel more compassion for myself, whereas I used to berate myself for being "too weak" to resist behaviors which seemed out of my control. And ultimately, it has taught me to become mindful of this predisposition I have so that when I notice an instinctive shift toward the disordered eating mentality, I can refocus my thoughts or actions in a much healthier, kinder direction.    

Sources

1. Suisman, J. et al, "Genetic and Environmental Influences on Thin-Ideal Internalization." International Journal of Eating Disorders, October 2012.
2. Bulik, C. et al, "Significant Locus and Metabolic Genetic Correlations Revealed in Genome-Wide Association Study of Anorexia Nervosa." American Journal of Psychiatry, June 2017.