All eating disorders are complex, and it's not known specifically what causes bulimia. It's thought that a variety of factors are involved, including biological, psychological and sociocultural issues. A mix of family history, social factors and personality is also involved.

While bulimia often starts in the teen years, it usually lasts into adulthood and is a long-term disorder. Other factors include:

  • Genetics. Some people may be genetically vulnerable to developing bulimia. Young women with a biological sister or mother with an eating disorder are at higher risk, for example, suggesting a possible genetic link. In addition, there's some evidence that serotonin, a naturally occurring brain chemical, may influence eating behaviors because of its connection to the regulation of food intake.

  • Psychological and familial. People with bulimia may have low self-worth as well as perfectionism. They may have trouble controlling impulsive behaviors, managing moods or expressing anger. The families of people with bulimia may tend to have more conflicts, along with more criticism and unpredictability. There may be a history of sexual abuse.

  • Cultural Modern Western culture generally cultivates and reinforces a desire for thinness. Success and worth are often equated with being thin, which is reinforced by peer pressure, particularly among young girls.