What Causes an Eating Disorder?
Eating disorders are complex illnesses with a genetic component that can be affected by a wide variety of biological and environmental variables.
Eating disorders include a range of conditions that involve an obsession with food, weight and appearance. The obsession is often so strong that it disrupts an individual’s health, social and familial relationships, occupations and daily activities. It is estimated that over 10 million people in the United States suffer from eating disorders such as anorexia, bulimia, and binge eating disorder, and the statistics are growing.
Research on the causes of eating disorders is constantly evolving, and we continue to gain increased insight into risk factors that may contribute to the illness. However, the answers remain multi-factorial, and they reflect a complex combination of biopsychosocial factors that may intersect differently for each person.
Several major risk factors for eating disorders are outlined below.
Increasing numbers of family, twin, and adoption research studies have provided compelling evidence to show that genetic factors contribute to a predisposition for eating disorders.1 In other words, individuals who are born with certain genotypes are at heightened risk for the development of an eating disorder. This also means that eating disorders are heritable. Individuals who have had a family member with an eating disorder are 7-12 times more likely to develop one themselves. Newer research is exploring a possible epigenetic influence on eating disorder development. Epigenetics is a process by which environmental effects alter the way genes are expressed.
Some of the genes that have been identified to contribute to eating disorders are associated with specific personality traits. These aspects of personality are thought to be highly heritable and often exist before the eating disorder and can persist after recovery.2,3 The following traits are common among people who develop an eating disorder but all of these personality characteristics can exist in the absence of an eating disorder as well.4,5
- obsessive thinking
- sensitivity to reward and punishment, harm avoidance
- neuroticism6 (emotional instability and hypersensitivity)
- impulsivity, especially in bulimia nervosa
- rigidity and excessive persistence, especially in anorexia nervosa
Even in healthy individuals without eating disorders, states of semi-starvation have been shown to trigger obsessive behavior around food, depression, anxiety and neuroticism that promote a continued cycle of starvation7. Additionally, brain imaging studies have shown that people with eating disorders may have altered brain circuitry that contributes to eating disorders.8,9 Differences in the anterior insula, striatal regions, and anterior ventral striatal pathway have been discovered. Problems with the serotonin pathway have also been discovered.10,11 These differences may help to explain why people who develop anorexia nervosa are able to inhibit their appetite, why people who develop binge eating disorder are vulnerable to overeating when they are hungry, and why people who develop bulimia nervosa have less ability to control impulses to purge.
Traumatic events such as physical or sexual abuse sometimes precipitate the development of an eating disorder.12-14 Survivors of trauma often struggle with shame, guilt, body dissatisfaction and a feeling of a lack of control. The eating disorder may become the individual’s attempt to regain control or cope with these intense emotions. In some cases, the eating disorder is an expression of self-harm or misdirected self-punishment for the trauma. As many as 50% of those with eating disorders may also be struggling with trauma disorders. It’s important to treat both conditions concurrently in a comprehensive and integrated approach which is why The Center for Eating Disorders offers a specialized treatment track for women and men with eating disorders who’ve also experienced trauma.
Coping Skill Deficits
Individuals with eating disorders are often lacking the skills to tolerate negative experiences. Behaviors such as restricting, purging, bingeing and excessive exercise often develop in response to emotional pain, conflict, low self-esteem, anxiety, depression, stress or trauma. In the absence of more positive coping skills, the eating disorder behaviors may provide acute relief from distress but quickly lead to more physical and psychological harm. Instead of helping, the eating disorder behaviors only serve to maintain a dangerous cycle of emotional dysregulation and numbing feelings. Effective treatment for the eating disorder involves education about and practice of alternative coping mechanisms and self-soothing techniques such as in Dialectic Behavior Therapy.
Our media’s increased obsession with the thin-ideal and industry promotion of a “perfect” body may contribute to unrealistic body ideals in people with and without eating disorders.15,16 An increase in access to global media and technological advances such as Photoshop and airbrushing have further skewed our perception of attainable beauty standards. In 1998, a researcher documented the response of adolescents in rural Fiji to the introduction of western television.17,18 This new media exposure resulted in significant preoccupations related to shape and weight, purging behavior to control weight, and negative body image. This landmark study illustrated a vulnerability to the images and values imported with media. Given that many individuals exposed to media and cultural ideals do not develop clinical eating disorders, it may be that individuals already at-risk, have increased vulnerability to society’s messages about weight and beauty and, perhaps, seek out increased exposure to them.
Dieting is the most common precipitating factor in the development of an eating disorder. In the U.S., more than $60 billion is spent every year on diets and weight-loss products. Despite dieting’s 95-98% failure rate, people continue to buy dangerous products and take extreme measures to lose weight. Restrictive dieting is not effective for weight loss and is an unhealthy behavior for anyone, especially children and adolescents. For individuals who are genetically predisposed to eating disorders, dieting can be the catalyst for heightened obsessions about weight and food. Dieting also intensifies feelings of guilt and shame around food which may ultimately contribute to a cycle of restricting, purging, bingeing or excessive exercise. 9.5 out of 10 people who lose weight through dieting gain back all of their weight within 1-5 years; half of them gain back to a weight that’s above their starting weight. More worrisome though is that dieting is associated with higher rates of depression and eating disorders and increased health problems related to weight cycling. Intuitive eating and the health-at-every size paradigms are recommended as alternatives to diets for people looking to improve their health and overall well-being.
What About Family?
Unfortunately, in the past, parents were often blamed as the cause of their child’s eating disorder. As more research is done on the diverse contributing factors discussed above, it becomes more and more clear that this is not the case. While stressful or chaotic family situations may intersect with other triggers to exacerbate or maintain the illness, they do not cause eating disorders. Its also important to note that some family dynamics, which were once assumed to be precursors to an eating disorder, may actually develop as a response to a family member’s struggle with an eating disorder. The Academy of Eating Disorders (AED) released a position paper that clarifies the role of the family in the acquisition of eating disorders. The paper points out that there is no data to support the idea that eating disorders are caused by a certain type of family dynamic or parenting style. Alternatively, there is strong evidence families play an integral role in the recovery process. In particular, family-based treatment for younger patients, implemented early on in their illness, leads to positive results and improvements in conjunction with professionally guided family interventions. The family is an integral system in the healthy development of a child. While parents and families are not to blame for eating disorders, they can play a role in helping kids establish a positive body image, healthy coping skills and eating competence which are all important protective factors against eating disorders.
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