Eating disorders are believed to arise from a combination of physical, psychological and environmental factors. Research into the potential causes of eating disorders is ongoing and continuously developing. In the past decade, studies have shifted focus to biological factors to evaluate whether there is a genetic predisposition to eating disorders.

Compelling evidence has shown that genes influence the development of an eating disorder. Genetic factors create a predisposition that puts a person at risk for acquiring an eating disorder. Research has also shown that eating disorders are heritable, meaning that a person is more likely to develop an eating disorder if a close family member has one.

Eating Disorders and Heredity

Although family history can elevate a person’s risk for developing an eating disorder, it does not necessarily guarantee it. Eating disorders can be hereditary due to genetic factors that make a person more susceptible but is not the sole reason for the development of a disorder.

Certain genes linked to personality traits have been shown to contribute to eating disorders. These personality factors are pervasive, enduring and extremely heritable. Some personality traits include obsessive thinking, perfectionism and emotional instability. Other traits include rigidity, impulsivity, hypersensitivity and harm avoidance. These traits elevate a person’s predisposition to acquiring an eating disorder.

Biological Reasons for Eating Disorders

Research studying eating disorders, genetics and biological factors show that vulnerability in biological processes may be genetic. Biological reasons for eating disorders are related to neural pathways, biochemistry and structures in the brain. Abnormalities in brain structure, chemicals in the brain and overall brain activity can play a role in the attainment of an eating disorder.

Biological factors of eating disorders can be related to deficiencies in areas of the brain linked with emotion, motivation and goal-directed behaviors, or can result from discrepancies in inhibitory and reward systems. Hormonal influences and disturbances to brain structures that are associated with the release of hormones can be another biological cause of eating disorders.

Do Eating Disorders Run in Families?

Research has shown that having a parent or sibling with an eating disorder elevates a person’s risk of developing an eating disorder. Other family factors in eating disorders relate to the household that a person is raised in and the messages that they receive from family members and caregivers. Family influence on eating disorders can occur when a family member is critical of a person’s weight, body or looks. Individuals that are raised by controlling parents who value thinness can develop a distorted body image.

Environmental Causes of Eating Disorders

Environmental influences on eating disorders can be related to pop culture, media and societal expectations. Exposure to media and the depiction of actors, actresses and movie stars can have a significant impact on the way that a person perceives themselves. Other environmental causes of eating disorders can be related to being criticized, teased, bullied or critiqued about weight from family or peers. Messages from others and social comparisons can lead to faulty body image and self-perceptions.

In determining whether eating disorders are genetic or environmental, they are a combination of both factors. There is no clear-cut cause for an eating disorder, as it is acquired from a multitude of biological, genetic, psychological and environmental factors.