Learning Objectives
- Describe the biological causes of feeding and eating disorders.
- Describe the cognitive causes of feeding and eating disorders.
- Describe the sociocultural causes of feeding and eating disorders.
- Describe how personality traits are the cause of feeding and eating disorders.
What causes eating disorders? While researchers have yet to identify a specific cause of eating disorders, the most compelling argument to date is that eating disorders are multidimensional disorders. This means many contributing factors lead to the development of an eating disorder. While there is likely a genetic predisposition, there are also environmental, or external factors, such as family dynamics and cultural influences that impact their presentation. Research supporting these influences is well documented for anorexia nervosa and bulimia nervosa; however, seeing as BED has only just recently been established as a formal diagnosis, research on the evolvement of BED is ongoing.
Biological
There is some evidence of a genetic predisposition for eating disorders, with relatives of those diagnosed with an eating disorder being up to six times more likely than other individuals to be diagnosed also. Twin concordance studies also support the gene theory. If an identical twin is diagnosed with anorexia, there is a 70% percent chance the other twin will develop anorexia in their lifetime. The concordance rate for fraternal twins (who share less genes) is 20%. While not as strong for bulimia, identical twins still display a 23% concordance rate, compared to the 9% rate for fraternal twins.
In addition to hereditary causes, disruption in the neuroendocrine system is common in those with eating disorders (Culbert, Racine, & Klump, 2015). Unfortunately, it’s difficult for researchers to determine if these disruptions caused the disorder or have been caused by the disorder, as manipulation of eating patterns is known to trigger changes in hormone production. With that said, researchers have explored the hypothalamus as a potential contributing factor. The hypothalamus is responsible for regulating body functions, particularly hunger and thirst (Fetissov & Mequid, 2010). Within the hypothalamus, the lateral hypothalamus is responsible for initiating hunger cues that cause the organism to eat, whereas the ventromedial hypothalamus is responsible for sending signals of satiation, telling the organism to stop eating. Clearly, a disruption in either of these structures could explain why an individual may not take in enough calories or experience periods of overeating.
Cognitive
Some argue that eating disorders are, in fact, a variant of obsessive-compulsive disorder (OCD). The obsession with body shape and weight—the hallmark of an eating disorder—is likely a driving factor in anorexia nervosa. Distorted thought patterns and an over-evaluation of body size likely contribute to this obsession and one’s desire for thinness. Research has identified high levels of impulsivity, particularly in those with binge eating episodes, suggesting a temporary lack of control is responsible for these episodes. Post binge-eating episode, many individuals report feelings of disgust or even thoughts of failure. These strong cognitive factors are indicative as to why cognitive-behavioral therapy is the preferred treatment for eating disorders.
Sociocultural
Eating disorders are overwhelmingly found in Western countries where there is a heavy emphasis on thinness—a core feature of eating disorders. It is also found in countries where food is in abundance, as in places of deprivation, round figures are viewed as more desirable (Polivy & Herman, 2002). While eating disorders were once thought of as disorders of higher SES, recent research suggests that as our country becomes more homogenized, the more universal eating disorders become.
10.4.3.1. Media. One commonly discussed contributor to eating disorders is the media. The idealization of thin models and actresses sends the message to young women (and adolescents) that to be popular and attractive, you must be thin. These images are not isolated to magazines, but are also seen in television shows, movies, commercials, and large advertisements on billboards and hanging in store windows. With the emergence of social media (e.g., Facebook, Snapchat, Instagram), exposure to media images and celebrities is even easier. Couple this with the ability to alter images to make individuals even thinner, it is no wonder many young people become dissatisfied with their body (Polivy & Herman, 2004).
10.4.3.2. Ethnicity. While eating disorders are not solely a “white woman” disorder, there are significant discrepancies when it comes to race, especially for anorexia nervosa. Why is this? Research indicates that black men prefer heavier women than do white men (Greenberg & Laporte, 1996). Given this preference, it should not be surprising that black women and children have larger ideal physiques than their white peers (Polivy & Herman, 2000). Since black women are less driven to thinness, black women would appear to be less likely to develop anorexia; however, findings suggest this is not the case. Caldwell and colleagues (1997) found that high-income black women were equally as dissatisfied as high-income white women with their physique, suggesting body image issues may be more closely related to SES than that of race. The race discrepancies are also less significant in BED, where the prominent feature of the eating disorder is not thinness (Polivy & Herman, 2002).
10.4.3.3. Gender. Males account for only a small percentage of eating disorders. While it is unclear as to why there is such a discrepancy, it is likely somewhat related to cultural desires of women being “thin” and men being “muscular” or “strong.”
Of men diagnosed with an eating disorder, the overwhelming percentage of them identified a job or sport as the primary reason for their eating behaviors (Strother, Lemberg, Stanford, & Turberville, 2012). Jockeys, distance runners, wrestlers, and bodybuilders are some of the professions identified as most restrictive regarding body weight.
There is some speculation that males are not diagnosed as frequently as women due to the stigma attached to eating disorders. Eating disorders have routinely been characterized as a “white, adolescent female” problem. Due to this bias, young men may not seek help for their eating disorder in efforts to prevent labeling (Raevuoni, Keski-Rahkonen & Hoek, 2014).
10.4.3.4. Family. Family influences are one of the strongest external contributors to maintaining eating disorders. Often family members are praised for their slenderness. Think about the last time you saw a family member or close friend- how often have you said, “You look great!” or commented on their appearance in some way? The odds are likely high. While the intent of the family member is not to maintain maladaptive eating behaviors by praising the physical appearance of someone struggling with an eating disorder, they are indirectly perpetuating the disorder.
While family involvement can help maintain the disorder, it can also contribute to the development of an eating disorder. Families that emphasize thinness or place a large emphasis on physical appearance are more likely to have a child diagnosed with an eating disorder (Zerbe, 2008). In fact, mothers with eating disorders are more likely to have children who develop a feeding/eating disorder than mothers without eating disorders (Whelan & Cooper, 2000). Additional family characteristics that are common among patients receiving treatment for eating disorders are enmeshed, intrusive, critical, hostile, or overly concerned with parenting (Polivy & Herman, 2002). While there has been some correlation between these family dynamics and eating disorders, they are not evident in all families of people with eating disorders.
Personality
There are many personality characteristics that are common in individuals with eating disorders. While it is unknown if these characteristics are inherent in the individual’s personality or a product of personal experiences, the thought is eating disorders develop due to the combination of the two.
10.4.4.1. Perfectionism. It should come as no surprise that perfectionism, or the belief that one must be perfect, is a contributing factor to disorders related to eating, weight, and body shape (particularly anorexia nervosa). While an exact mechanism is unknown, it is believed that perfectionism magnifies normal body imperfections, leading an individual to go to extreme (i.e., restrictive) behaviors to remedy the flaw (Hewitt, Flett & Ediger, 1995).
10.4.4.2. Self-Esteem. Self-esteem, or one’s belief in their worth or ability, has routinely been identified as a moderator of many psychological disorders, and eating disorders are no exception. Low self-esteem not only contributes to the development of an eating disorder but is also likely involved in the maintenance of the disorder. One theory, the transdiagnostic model of eating disorders, suggests that overall low self-esteem increases the risk for over-evaluation of body, which in turn, leads to negative eating behaviors that could lead to an eating disorder (Fairburn, Cooper & Shafran, 2003).
Key Takeaways
You should have learned the following in this section:
- Biological causes of eating disorders include a genetic predisposition and disruption in the neuroendocrine system.
- Cognitive causes of eating disorders include distorted thought patterns and an over-evaluation of body size.
- Sociocultural causes of eating disorders include the idealization of thin models and actresses by the media, SES, gender, and family involvement.
- The personality trait of perfectionism and low self-esteem are contributing factors to disorders related to eating, weight, and body shape.
Review Questions
- Define multidimensional disorders?
- What evidence is there to suggest eating disorders are biologically driven?
- According to the cognitive theory, eating disorders may be a variant of what other disorder?
- Discuss the four sociocultural subgroups that explains development of eating disorders.
- What are the two personality traits most commonly used to describe behaviors associated with eating disorders?
