Biological causes of bulimia nervosa
Eating disorders of all kinds were once considered primarily social disorders, impacted by factors like peer pressure and cultural norms around thinness. But thanks to developments in technology, doctors, scientists, and researchers are increasingly finding biological factors as potential bulimia causes.
Inherited traits
Many eating disorders, including bulimia nervosa, are now considered at least “moderately heritable,” meaning they can be passed down through families.1 One ground-breaking study on the subject found genetic similarities in 57% of the study’s participants.1
It's usually not the disorder, per se, that gets passed down, but rather several traits, such as how someone reacts to stress, that can make someone more susceptible to developing BN or other eating disorders.1
These inherited traits can act as causes of bulimia in several ways, from the types of genes and hormones they trigger in a person to the way they make someone's brain interpret signals from the body.1
Hormonal triggers
Research has found a link between female puberty and the development of eating disorders.2
One study found that, up to age eleven, there were no genetic influences on the development of eating disorders in girls. But by age 17, at least 50% of recorded cases were caused by biology.2
A follow-up to this finding discovered that estrogen, called estradiol, plays a role. Primarily responsible for the development and growth of reproductive organs, the hormone goes into overdrive during puberty. This second study concluded this excess estradiol was also “switching on” specific genes that could lead to the development of eating disorders in affected girls.3
Brain activity
Another study found the neurological pathways in the brain responsible for motivation and reinforcement as another potential cause of bulimia. Typically, these systems ensure a person seeks enough nutrition for the body and stops eating once they’re satiated. But disruption of these pathways was found in people with bulimia.
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Brain activity was also connected to several major
symptoms of bulimia, including both binging and
purging behaviors. In one study,
binge eating was tied to an overwhelmed reward system in the brain, with people becoming more susceptible to binge eating the more often they participated in the behavior.
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Research has also found the purging behaviors of bulimia nervosa may be linked to biology, but scientists are continuing to explore the subject. At least one finding suggested that the neurotransmitter acetylcholine, which helps transmit the feeling of satiety, may be overwhelmed by the feel-good hormones involved in binge eating but brought back to more normal levels by the action of purging.
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Psychological causes of bulimia
From a psychological standpoint, there are many potential causes of bulimia.
BN has been connected to several comorbid conditions, which are disorders that occur at the same time and often play off each other. Some of the most closely linked conditions include obsessive-compulsive disorder (OCD), perfectionism, and a behavior called trait urgency, which is the tendency to react recklessly in response to stress.1,5
Bulimia is also highly comorbid with various mood disorders, especially anxiety disorders and depression.12 Many people with BN struggle with concurrent drug and alcohol abuse.12
What causes bulimia in people with these risk factors depends on various things. However, individuals often use eating as a coping mechanism to deal with the stress of these additional mental health conditions.5
Environmental bulimia causes
Most studies on causes of bulimia and other eating disorders have focused on sociocultural influences. Many scientists have long attributed the development of these disorders almost exclusively to environmental factors.
While the examination of biological causes of bulimia continues to expand and round out scientific knowledge on the issue, many outside factors play a significant role in developing BN.
Environmental stress and history of trauma
Sadly, bulimia nervosa has been linked to a history of stress or
trauma.
A disproportionate amount of people participating in eating disorder studies have reported traumatic pasts, including instances of sexual assault, physical and emotional abuse, teasing and bullying, and the loss of a parent.
7 One study found up to 25% of participants with bulimia showed signs of post-traumatic stress disorder.
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While these scenarios aren't direct causes of bulimia, they may serve as triggers that kick off unhelpful coping mechanisms like binge eating and purging.
Role modeling
What someone is exposed to growing up can also play a role in the types of
eating habits—or coping mechanisms—they develop, along with the kinds of unhelpful thoughts about body shape or low self-esteem that often power eating disorders.
This idea is supported by research that shows that parental role modeling can have a significant influence on a person’s feelings about both food and
body image.
6 In fact, the study found a significant number of daughters mimicked their mothers’ purging behaviors, which are the hallmark signs of bulimia nervosa.
6
Peer pressure and cultural expectations
Social and cultural pressure to remain thin have classically been considered the main causes of bulimia—and there is still plenty of research that points to their role in developing the disorder today.
A huge number of studies have been conducted on the subject, with one overview summarizing that more than 25 different reports had successfully linked body dissatisfaction and signs of bulimia to both peer and family influence.
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Specifically, the development of BN was linked to:
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- Weight-related bullying
- Interaction between peers, including sharing concerns over weight and body image
- "Likability," or the pressure to be well-liked, and the idea that thinness makes someone more "likable"
In particular, likability has also been connected to the images perpetuated on social media and in popular culture, which favor thin women and muscular men. One recent study found that more than 70% of models were found to be underweight, and more than 75% were less than 85% of their ideal body weight.
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Treatment of bulimia nervosa
While there are many causes of bulimia, there are many treatments for the condition, as well. And no matter what causes bulimia in a person, it's possible to overcome the disorder. In fact, nearly 74% of people struggling with BN fully recover after seeking treatment.11
Several types of therapy have been found to be especially effective against BN, including:
- Cognitive behavioral therapy (CBT): This type of therapy operates on the idea that unhelpful behaviors are caused by unhelpful thoughts. CBT helps patients learn to recognize these patterns and teaches them strategies for changing them, with the eventual goal of eliminating disordered thoughts and the behaviors they cause, all together.
- Self-help: This type of care has also been found to be a useful treatment for bulimia nervosa. Mostly mirroring the concepts of CBT, self-help allows a patient to practice these techniques at their own pace, by working through a notebook or an online course, with little or no interaction with a therapist.
- Interpersonal psychotherapy (IPT): This modality focuses on helping people understand and better navigate the social dynamics in their life. IPT has been found especially helpful for reducing binge eating behaviors, partly by teaching patients how to manage boundaries and helping them improve self-esteem.13
Finding help for bulimia nervosa
If you or a loved one are struggling with BN or another eating disorder, it's crucial to seek help from a mental health professional. These conditions can be dangerous or even deadly if left untreated.
Thankfully, there are many ways to treat bulimia nervosa. Several types of therapies have shown promise for reducing binge eating behaviors and improving body image and self-esteem. Your primary care physician or therapist can help you determine the best care.
Remote care for bulimia nervosa
At Within, we understand the many causes of bulimia and factors that must be considered, so we have a team of multi-disciplinary experts to create individualized treatment plans for each patient. We ensure all of our patients get the kind of care they need for their specific history and needs.
Contact us today to see how you can get started on the road to recovery.
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