Etiology of Eating Disorders

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Multiple risk factors can lead to the development of eating disordersOpens in new window, including genetic predisposition, family disturbance, adverse life events, low self-esteem, high anxiety, identity and self-competence concerns, interpersonal conflicts, and social and cultural pressures to be thin. These factors can influence young women and increasingly men to reduce their weight by excessive dieting, exercising, binge/purge routines, and other weight-reducing behavior.

Indeed, several factors interacting with each other are considered to potentially cause the development of eating disorders. Among these are predisposing factors, which are believed to increase the vulnerability of a person to an eating disorder in the presence of precipitating factors.

Precipitating factors, such as stressful life events, are often described as “the last straw” by clients.

The interaction between predisposing and precipitating factors is believed to lead to the development of an eating disorder. Once the disorder has developed, perpetuating factors keep the person in the cycle of restrictions and compulsions, therefore maintaining the illness.

Predisposing Factors

Predisposing factors are believed to increase the individual’s vulnerability to develop an eating disorder.

1.  Personality

Characteristics that promote the development of a fragile and anxious personality increase the risk of an individual developing an eating disorder. Many personality characteristics differ depending on the eating disorder and are presented in Table X-2.

Other psychological factors related to eating disorders involve insecure attachments and separation-individuation problems. In fact, identity formation depends on the ability to move through the separation-individuation continuum of normal development. It allows individuals to experiment, learn, identify, evaluate, and compare before deciding what and whom to become (Catellini, Trisolini, & Rica, 2014).

Tension between the need to belong and the desire to be independent is influential in eating disorder development. Moreover, low self-esteem, difficulties in identity formation, negative self-image, and difficulty in establishing fulfilling and meaningful relationships are believed to put people at risk for developing eating disorders (Doris, Westwood, Mandy, & Tchanturia, 2014; Farstad et al., 2016).

People with autistic spectrum disorderOpens in new window traits are particularly at risk, and high levels of perfectionism is also a significant risk factor. Individuals with anorexia nervosaOpens in new window are more likely to have a self-oriented perfectionism (excessive expectations of the self), whereas individuals with binge eating disorderOpens in new window are more likely to experience a socially prescribed perfectionism (feel that others demand high standards) (Sherry et al., 2014).

2.  Biology

There is an important body of literature concerning biology and its links to eating disorders, including strong evidence that serotonin plays a role in the development of eating disorders.

More precisely, on the one hand, serotonin dysregulation (i.e., variability in the concentration levels of serotonin and alteration in its functions) contributes to different signs and symptoms of eating disorders. On the other hand, evidence shows that dieting can result in reduced brain serotonin synthesis, leading to more serotonergic dysregulation, which creates a vicious circle in which eating disorder symptomatology is maintained (Gellynck et al., 2013).

Moreover, some personality traits, such as impulsivity and perfectionism, have been linked to variations in serotonin level (Alonso, Cortazar, Guillen, Fuentes, & Remesal, 2016). Finally, increasing evidence links traumatic stress, such as child abuse, to altered serotonin activity (Akkermann, Kaasik, Kiive, Nordquist, Oreland, & Harro, 2012).

The specific mechanisms of these interactions are still being investigated, but current evidence is strong and suggests promising theoretical and clinical implications for understanding and treating eating disorders. Over the past 10 to 15 years, there have been considerable advances in understanding the genetic contribution to eating disorders.

Genetic and hereditary studies and twin siblings with an eating disorder are at higher risk of developing eating disorders. Ongoing genetic studies focus on understanding the role of genes as well as how the interaction between genes and the environment affects development of an eating disorder.

3.  Family Functioning

Interactions within the family system can influence the development of an eating disorder, just as eating disorders can influence the family’s functioning and its dynamic.

However, specific family characteristics can increase an individual’s sensitivity to develop an eating disorder (Loeb, Le Grange, & Lock, 2015), including:

• Alcohol and/or drug abuse in the family
• Family violence
• Sexual abuse
• Overvaluing of appearance and thinness
• Eating habits organized around diets and food restriction
• Lack of opportunity to develop one’s independence and autonomy
• Overprotectiveness
• Rigidity
• Excessive or absence of parental control

It is important for occupational therapy practitioners to recognize the impact of caring for someone with an eating disorder on the career’s role, and how the caregiver’s reactions may impact his or her own occupational performance and engagement — as well as that of the person with the eating disorder. Educating and enabling carers to create environments that facilitate adaptive changes for their loved ones is important.

4.  Social and Cultural Influences

Increasing evidence indicates that social and cultural influences play an important role in the development of eating disorders (Smolak & Chun-Kennedy, 2013; Wong, 2015). Increasingly, social pressures glorify thinness and associate it with success and happiness.

Social reinforcement and cultural norms value people on the basis of physical appearance and place value on obtaining the perfect body (Costa & Melnik, 2016). The image of Western women promoted in the media influences body image and self-esteem. It sanctions thinness as beauty (Culbert, Racine, & Klump, 2015).

Despite the fact that most fashion magazine photos are altered to fit certain standards, girls and women still aspire to them as symbols of beauty and happiness. This sends the message that to be popular and successful one must be strikingly thin. Also, being overweight is associated with laziness and lack of discipline. People who are overweight can be alienated, rejected by society, and subject to discrimination (Puhl & Suh, 2015).

Strong evidence has supported links between exposure to mass media and low self-esteem and increased body dissatisfaction, which contribute to eating disorders (Culbert, Racine, & Klump, 2015). Earlier studies demonstrated that mass media promoted an ever thinner body type with top models, actresses, and other cultural female icons having become significantly thinner (Dakanalis et al., 2015).

In addition, controlling weight and refraining from eating certain foods has been perceived as showing strength and determination for several years (Luo, Forbush, Williamson, Markon, & Pollack, 2013). To someone with low self-esteem, the pressure to be thin that is promoted by the mass media, in combination with body dissatisfaction, can increase feelings of inadequacy and trigger a cycle of food restriction and dieting.

Technology and, more specifically, Internet accessibility of social media and networking sites on portable devices such as mobile phones, computers, and tablets means instantaneous and constant contacts with family, friends, world-wide news, celebrities, and even complete strangers. When exploring the impacts of exposure to the Internet appearance-related sites is linked to weight dissatisfaction and a drive for thinness (Tiggemann & Miller, 2010).

Precipitating Factors

Negative perceptions and thoughts about oneself, one’s appearance, the environment, and/or the future can precipitate the development of disordered and unhealthy eating habits, which can eventually result in an eating disorder. A comment on one’s body or appearance, a failure, a defeat or a setback, a relationship break-up, or major stress can all precipitate an eating disorder (Backholm, Isoma, & Birgegard, 2013; Jang, 2013).

A specific environmental event linked to eating disorder vulnerability is changes in school from one level to another (e.g., moving from primary school to high school, or from high school to college or university) because students must adapt to a new environment with new demands and higher expectations (Troop, 2012).

A study of high school students found that eating disorders were highly related to substance use (Levine, 2014). Although the exact nature of the relationship is unknown, substance abuse may increase vulnerability to eating disorders. Importantly, no single event will lead to an eating disorder; rather, it involves the interactions between multiple factors that significantly increase the risk of developing an eating disorder.

Perpetuating Factors

Once an eating disorder has developed, the early changes are often satisfying and seen as an improvement by people around the individual, whether family members, peers, or even a stranger.

Indeed, it is common to hear someone being complimented on his or her new figure and weight loss. Unfortunately, comments of that sort reinforce the disordered eating attitudes and behaviors in people who are already vulnerable (Treasure et al, 2008). Consequently, the vulnerable individual will develop strategies to maintain the weight loss and/or increase the restriction and obsessive thoughts about weight and appearances (Pugh & Waller, 2016).

Also, the effects of fasting and food restrictions can contribute to the development of cognitive distortions that perpetuate the disorder. For example, the individual thinks of him or herself as strong and in control, as demonstrated by the ability to restrict food intake.

Protective Factors

Although rarely addressed in the literature, protective factors are now considered when looking at the development of eating disorders (Daly, 2015; Gongora, 2014).

These factors can be grouped into individual, family, social categories. Hence, developing protective factors can play an important role in preventing the developmental process of eating disorders. Protective factors include the following:

• Assertion skills, independence, and autonomy
• Opportunity to invest in a variety of roles
• Ability to use stress management techniques
• Positive self-esteem
• Family environment that is not overly concerned with appearance, beauty, and thinness
• Family relationships that allow the person to develop a sense of belonging and individuation
• Social environment that is not overly concerned with beauty and thinness
• Spirituality

These protective factors can guide families and health care specialists in the development of prevention strategies.