The Causes of Bulimia Nervosa

Bulimia nervosa (BN) is a complex eating disorder affecting millions of people of all genders in the United States. (1) The causes of bulimia nervosa can range from person to person, and include multiple factors. Some individuals are more heavily influenced by environmental factors and genetics, while others develop bulimia nervosa due to mental health conditions or their relationship to exercise and dieting.

Woman thinking

Several factors play a role in causing BN and may vary among individuals, including environment, genetics, co-occurring mental health conditions, exercise, and diet. Multiple factors can contribute to someone’s eating disorder.

Environmental Factors

Environmental factors are aspects of one’s living, or working space, that influence their thoughts or behaviors. Social media is one of the most common environmental factors that can contribute to the development of eating disorders. The average person spends nearly two and a half hours on social media each day, and the constant curated feed can significantly impact their thoughts and feelings. (2)

People spend around 2.5 hours on social media each day.

One study dug into social media and found overwhelming evidence suggesting many posts glorify thin bodies and weight loss. (3) People consistently see images of edited photos and videos from fitness models and influencers focusing on their adherence to the thin ideal.

Beneath these posts are comments on their bodies and how good other people think they look, causing a false reality that thin, muscular, young bodies are the only standard for beauty. And when an individual compares themselves unfavorably to these curated and modified images, it can cause negative feelings about themselves and ultimately lead to disordered eating.

This harmful beauty standard goes beyond social media. It’s common in film, television, magazines, and advertisements. Beyond promoting inaccessible body ideals, it emphasizes physical appearance as an important quality, especially for girls and women, but also for people of all genders. (3)

Media often places value on beauty over other aspects of a person, putting an added pressure on people to look a certain way. These ideals are further embedded into society and shared among peers, although many beauty standards are unattainable, and individuals may turn to disordered eating to attempt to manipulate their size and weight.

Woman working on computer


Research suggests that genetic factors may play a role in the development of bulimia nervosa. One study looked at families and found an increased rate of BN and other eating disorders in people with a family history. (4) While some argue that family history could be an environmental factor, meaning disordered eating comes from seeing relatives live with eating disorders, this study dug further into the question of genetics with twin studies.

These twin studies looked at identical and fraternal twins and compared various traits to distinguish between genetics and environment. Identical twins share the same genes, while fraternal twins only share half.

By observing the two groups, the study results found eating disorder symptoms are moderately heritable, suggesting a genetic component to the behaviors of eating disorders. Research shows genetics can play a role in a person’s risk of developing a drug or alcohol addiction.

One study found those with genetic factors predisposing them to substance addiction also to have an increased risk of bulimia nervosa. (11) This study looked at families and twins who have a history of addiction. Those with a family history were more likely to develop BN, leading researchers to believe additive genetic factors may play a role in causing the disorder.

Mental Health Conditions

Some mental health conditions can increase a person’s risk for bulimia nervosa. Anxiety, depression, and obsessive-compulsive disorder are three common mental health conditions that commonly coexist with BN, yet it’s unclear if one causes the other. The challenging part about mental health conditions and eating disorders is knowing which came first.


In some instances, signs and symptoms of depression begin simultaneously as bulimia nervosa. In other cases, depression precedes a person’s eating disorder. (12) An individual may suffer from depression and feel unhappy about how they look. They may believe that to make themselves feel better, they need to look a certain way and will develop disordered eating behaviors to attempt to change their bodies.

In other instances, a person might develop BN and later experience depression because disordered eating is not making them feel or look the way they want, and results in other disruptions to their life.

Anxiety and Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is a form of anxiety that affects up to 41 % of people with eating disorders. (13) Like depression, OCD may develop simultaneously or before an eating disorder. Bulimia nervosa involves a cycle of binge eating and purging or compensating. These behaviors are often because of intrusive obsessive thoughts only reduced by compulsive behaviors such as binge eating and purging or compensating. It can also lead to excessive exercise to control one’s body.

Diet and Exercise

There is an emphasis on diet and exercise in American culture based on diet culture beliefs that individuals can and must control their health and body size through these behaviors. Many people initially choose to adjust their diet or begin exercising with good intentions. They may think that eating in a certain way or doing specific types of exercises will help them feel better or improve health outcomes.

However, in some individuals, this spiral into obsessive tendencies that may cause bulimia nervosa in some instances. Many dieting fads encourage restricting food, which can ultimately lead to deprivation.

When the body feels restricted from food or specific types of foods, it can trigger episodes of binge eating. (8) This cycle of restriction and binge eating can cause and continue the cycle of bulimia nervosa because individuals may feel guilty or anxious about their food.

They may feel anxious, guilty, or ashamed about binging and respond by purging or engaging in other compensatory behaviors Sometimes instead of purging, people will develop obsessive-compulsive behaviors around exercising as a compensatory behavior. Using exercise in this way is referred to as exercise bulimia. (9)

People with exercise bulimia may to closely track their calories during workouts, schedule their days around training, and will take little to no rest days to recover. They may also develop anxiety if they miss a workout or don’t burn a certain number of calories while exercising.

While dieting and exercise can increase the risk of developing bulimia nervosa in anyone, athletes have a higher risk, especially those who face pressure to conform to a specific aesthetic or weigh a specific weight. (10) Even athletes who are presumably healthy may suffer from compulsive exercise to reach their fitness goals.

Patient speaking with a doctor

Medical Complications of Bulimia

Bulimia nervosa is a severe eating disorder that can lead to multiple health concerns. Common medical complications associated with BN include:

  • Dehydration: Purging associated with BN, such as self-induced vomiting or laxative use, can cause dehydration. If the body is dehydrated, it can lead to additional complications such as kidney failure.
  • Heart conditions: Studies find there is an increased risk of cardiovascular disease in women who have bulimia nervosa. The most common heart diseases observed include ischemic heart disease, atherosclerosis, and cardiac conduction defects. (5)
  • Tooth decay: Individuals who partake in self-induced vomiting as a purging method may experience high rates of tooth decay. Acids in vomit can wear away on the tooth enamel. There is also an increased risk of tooth decay in people who binge on surgery foods and drinks.
  • Gum disease: Self-induced vomiting can also cause damage to the gums. The acid in vomit can cause inflamed gums, gingivitis, and gum disease. 
  • Digestive problems: Various digestive complications are associated with bulimia nervosa, including heartburn, nausea, diarrhea, bloating, and abdominal pain. BN can also lead to kidney failure and bowel shut down if left untreated. (6)
  • Anxiety and depression: Anxiety and depression often co-occur with bulimia nervosa. (7) People with BN may grow anxious about eating and weight while also experiencing depression around how they look and feel.


  1. Eating disorder statistics: General & Diversity stats: Anad. National Association of Anorexia Nervosa and Associated Disorders. (2022, June 8). Retrieved June 24, 2022, from
  2. Berrettini, W. (2004, November). The genetics of eating disorders. Psychiatry (Edgmont (Pa. : Township)). Retrieved from
  3. Gurd, J., Hanlon, A., & Bullock, L. (2022, June 1). Global Social Media Statistics Research Summary 2022 [June 2022]. Smart Insights. Retrieved June 24, 2022, from
  4. Spettigue, W., & Henderson, K. A. (2004, February). Eating disorders and the role of the Media. The Canadian child and adolescent psychiatry review. Retrieved June 24, 2022,
  5. Berrettini, W. (2004, November). The genetics of eating disorders. Psychiatry (Edgmont (Pa. : Township)). Retrieved from
  6. Tith, R. M., Paradis, G., Potter, B. J., Low, N., Healy-Profitós, J., He, S., & Auger, N. (2020). Association of Bulimia Nervosa with long-term risk of cardiovascular disease and mortality among women. JAMA Psychiatry, 77(1), 44.
  7. Center for Clinical Interventions. (n.d.). Gastrointestinal Problems in Eating Disorders. Center for Clinical Interventions. Retrieved June 24, 2022,—Information-Sheets/Eating-Disorders-Information-Sheet—17—Gastrointestinal-Problems.pdf 
  8. Levinson, C. A., Zerwas, S., Calebs, B., Forbush, K., Kordy, H., Watson, H., Hofmeier, S., Levine, M., Crosby, R. D., Peat, C., Runfola, C. D., Zimmer, B., Moesner, M., Marcus, M. D., & Bulik, C. M. (2017). The core symptoms of bulimia nervosa, anxiety, and depression: A network analysis. Journal of Abnormal Psychology, 126(3), 340–354.
  9. Zimmerman, J. (2022, May 16). Why dieting can lead to an eating disorder. HealthPartners Blog. Retrieved June 24, 2022,
  10. Healthline Media. (2017, July 26). Exercise bulimia: Symptoms, treatments, and more. Healthline. Retrieved June 24, 2022,
  11. Quinn, E. (2020, November 17). Even healthy athletes may binge and Purge. Verywell Fit. Retrieved June 24, 2022,
  12. Mazzeo, S. E., & Bulik, C. M. (2009). Environmental and genetic risk factors for eating disorders: What the clinician needs to know. Child and Adolescent Psychiatric Clinics of North America, 18(1), 67–82.
  13. American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, American Psychiatric Publishing, Washington, D.C., 2013: Pages 345-350.
  14. Neziroglu, F., & Sandler, J. (2009). The relationship between eating disorders and OCD part of the spectrum. International OCD Foundation. Retrieved June 24, 2022,

Last Update | 06 - 28 - 2022

Medical Disclaimer

Any information provided on the is for educational purposes only. The information on this site should not substitute for professional medical advice. Please consult with a medical professional if you are seeking medical advice, a diagnosis or any treatment solutions. is not liable for any issues associated with acting upon any information on this site.