Bulimia, Genetics, and Heritability

Contributor: Crystal Karges, MS, RDN, IBCLC for Eating Disorder Hope

summerfield-336672_640While no single factor can be pinpointed as the cause of bulimia nervosa, the role of genetics in eating disorder development has been increasingly understood.

Because the heritability factor is not as readily discussed, it is seems more straightforward to base our insight on these disorders on what we know, namely what is seen in our environment.

It is easier to make the connection between bulimia and:

  • Our surroundings
  • The culture we are in
  • The effects of mass media
  • Our upbringing
  • Social interactions
  • Other influences

While environment and experiences are contributing factors as well, genetics and heritability play a large piece of the puzzle in the development of bulimia and other eating disorders.

Understanding Genetics to Improve Treatment

Understanding the genetic factor of eating disorders is not only important for increasing awareness, but for improving treatment methods as well. Many researchers have uncovered the connection between our DNA, or genetic make-up, and the factors that would make women or men more susceptible to developing an eating disorder, such as bulimia.

Learning about the genetic component also helps break many of the stigmas that surround these psychiatric illnesses. Eating disorders are not merely dieting taken to the extreme. These are diseases with a neurobiological basis and should be treated as such.

Research in Genetics’ Relationship to Eating Disorders

woman-511849_640What research has been done in this area of genetics and eating disorders, and how can this help improve understanding and treatment for these mental health illnesses?

Researchers from the Maudsely Hospital in London discovered variations in the gene for serotonin in patients with eating disorders, finding that patients were twice as likely to have the variant gene, than women without eating disorders [1].

The serotonin system in the human body plays an important role in appetite regulation, impulse control and some social behaviors, among other functions.

Serotonin and Bulimia

Further studies completed by Dr. Walter Kaye at the University of California San Diego Eating Disorder Center have also discovered a connection between individuals with bulimia nervosa and abnormal levels of serotonin.

His research in this area found that recovered individuals still exhibited an abnormal serotonin level, which may have influenced increased negative moods and obsession with perfectionism[2].

What does this research translate into for someone with eating disorders? Abnormal levels of serotonin, which may be a result of genetic components, could influence character traits that increase susceptibility to bulimia.

Eating disorder behaviors could, in theory, also be a response to abnormal levels of serotonin, such as bingeing on foods high in carbohydrates, which would increase serotonin levels in the brain, inducing a feeling of pleasure.

Inheriting Traits that Are Passed Along Genes

Other research in this area has highlighted more than one gene that may contribute to the development of an eating disorder. Certain character and personality traits may be influenced by genetic factors, such as obsessionality, perfectionism, anxiety, and inhibition.

According to a review paper by Dr. Walter Kaye and Dr. Danyale McCurdy,

“It is very likely that such traits are what one genetically inherits since these seem to also be present in families of people with an ED. These traits reflect the interactions of many genes, each having a relative small influence. If someone has some of these GABA genes, perhaps they have an extra dose of anxiety and this may make it that much more difficult to recover.” [3].

There Is Still a lot to Learn

couple-407139_640These research discoveries are but the tip of the iceberg regarding the volume of information that is now being understood about genetics and eating disorders. Findings in the area of genetic influence on eating disorders have become a crucial component of treatment.

Treatment methods have become increasingly effective for individuals suffering from bulimia, and a large part of this is due to the understanding of genetics. Having treatment methods that address genetic influences, such as behavioral therapies, or medications for balancing chemical imbalances, can help improve the prognosis for individuals who are suffering with eating disorders, such as bulimia.

Bulimia is the result of many complex factors, including both environmental issues and genetics/heritability. Having a better understanding of the factors that encompass the risk for developing bulimia leads to greater awareness and treatment outcomes.

Community Discussion – Share your thoughts here:

How does highlighting the genetic influence on eating disorders help break the stigmas that surround these mental health illnesses?


  1. BBC News, “Genetic Clues to Eating Disorders”, http://news.bbc.co.uk/2/hi/health/259226.stm
  2. BBC News, “Brain Chemicals May Cause Bulimia.”
  3. Walter Kaye, MD, et al. Review of: “Genetic Association of Recovery from Eating Disorders: The The Role of GABA Receptor SNPs.” http://eatingdisorders.ucsd.edu/research/genetics/
    Role of GABA Receptor SNPs.” http://eatingdisorders.ucsd.edu/research/genetics/

Last Updated & Reviewed By: Jacquelyn Ekern, MS, LPC on November 11th, 2014
Published on EatingDisorderHope.com