Causes of Eating Disorders? A Complete Analysis of Risk & Causal Factors

Eating disorders are chronic and debilitating psychiatric illnesses that profoundly impact a person’s functioning. Rates of eating disorders are rapidly growing worldwide, meaning that effective strategies that prevent the onset of new eating disorder cases are urgently needed.

Understanding the risk factors for eating disorders may assist in the development and implementation of effective preventative strategies.

Eating disorders have no single cause – they result from the interaction of various biological and psychosocial factors. In this article, a review of the established biological, psychological, and social risk factors for eating disorders will be discussed.

Genetic Factors

Genetic factors are important for explaining why only a small proportion of people go on to develop an eating disorder despite being exposed to similar social contexts.

Eating disorders share a genetic basis, and studies on families and twins can provide compelling evidence for this¹Hinney, A, S Friedel, H Remschmidt, and J Hebebrand. 2004. “Genetic Risk Factors in Eating Disorders.” American Journal of Pharmacogenomics : Genomics-Related Research in Drug Development and Clinical Practice 4 (4): 209–23. [PubMed].

For example, those that are born with certain genotypes are at a much larger risk for developing eating disorders, and previous research has shown that the chances of developing an eating disorder increase tenfold when one has a family member with a history of an eating disorder²Hinney, A, S Friedel, H Remschmidt, and J Hebebrand. 2004. “Genetic Risk Factors in Eating Disorders.” American Journal of Pharmacogenomics : Genomics-Related Research in Drug Development and Clinical Practice 4 (4): 209–23. [PubMed].

Twin studies of eating disorders have also consistently produced high heritability estimates.

Heritability estimates are as high as 76% for anorexia nervosa, 83% for bulimia nervosa, and 41% for binge-eating disorder, which means that less than half of the risk variation can be accounted for by non-genetic factors!³Striegel-Moore RH, Bulik CM. Risk factors for eating disorders. American Psychologist. 2007;62(3):181..

Genes play a particularly influential role in eating disorder onset during puberty.  For example, more than 50% of the risk of developing an eating disorder during puberty is solely explained by genetic factors that emerge during this time⁴Klump KL, Perkins PS, Burt SA, et al. Puberty moderates genetic influences on disordered eating. Psychological Medicine. 2007;37(05):627-634.. This may explain why the age of onset for most eating disorder types are in the early teen years.

Serotonin, a neurotransmitter primarily responsible for happiness and wellbeing, is another genetic risk factor for eating disorders. Abnormal serotonin levels are found in people with bulimia nervosa and anorexia nervosa⁵Steiger H. Eating disorders and the serotonin connection: state, trait and developmental effects. Journal of Psychiatry and Neuroscience. 2004;29(1):20..

Abnormal serotonin levels, which may result from genetic components, could influence various personality and psychological traits (e.g., perfectionism, depression) that make one susceptible to developing an eating disorder⁶Steiger H. Eating disorders and the serotonin connection: state, trait and developmental effects. Journal of Psychiatry and Neuroscience. 2004;29(1):20..

Certain temperament styles that are risk factors for eating disorders are also highly heritable. Some of these temperament styles include:

1. Perfectionism
2. Obsessionality and ruminative thinking
3. Impulsivity
4. Neuroticism
5. Sensitivity to reward and punishment
6. Dichotomous thinking

Psychosocial Risk Factors

Psychological and social factors also play a role in the development of eating disorders.

Many of these factors interact with each other to cause eating disorders. Some of these risk factors include:

Dieting

Dieting is one of the strongest risk factors for eating disorders⁷Stice E. Risk and maintenance factors for eating pathology: a meta-analytic review. Psychological Bulletin. 2002;128:825-848..

Some studies have found that more than 50% of young men and women have dieted in an extreme fashion for weight loss purposes⁸Neumark-Sztainer D, Wall M, Guo J, et al. Obesity, disordered eating, and eating disorders in a longitudinal study of adolescents: how do dieters fare 5 years later? Journal of the American Dietetic Association. 2006;106:559-568..

Dieting heightens our preoccupations around food and eating, and increases our body image concerns. Because almost all diets cannot be sustained for long periods, people often find themselves going through cycles of restriction, binge eating, and purging⁹Fairburn CG, Cooper Z, Shafran R. Cognitive behaviour therapy for eating disorders: A “transdiagnostic” theory and treatment. Behavior Research and Therapy. 2003;41:509-528..

Body dissatisfaction

Body dissatisfaction refers to the subjective negative appraisal one has on their body.

Up to 70% of men and women are dissatisfied with their body, according to some studies¹⁰Fiske L, Fallon EA, Blissmer B, et al. Prevalence of body dissatisfaction among United States adults: Review and recommendations for future research. Eating behaviors. 2014;15(3):357-365..

Body dissatisfied people generally have low self-esteem and therefore go to extreme lengths to modify their body, such as engaging in extreme forms of dieting, using weight loss pills, and exercising compulsively, all of which play a role in the onset of eating disorders¹¹Fairburn CG. Cognitive behavior therapy and eating disorders. New York, NY: Guilford Press 2008..

Thin-ideal internalisation

The cultural ideal of female beauty portrayed in the media is synonymous with ultra-thinness.

The extent to which one “buys into” socially defined ideals of attractiveness (i.e., “thin-ideal internalisation”) is a major risk factor for developing an eating disorder.

Women who believe that “attractiveness = ultra-thinness” go onto develop body dissatisfaction because they will soon realise that this unrealistic body type cannot be achieved. They may then encourage them to engage in dangerous eating disorder behaviours (e.g., dieting, excessive exercise, starvation etc.) that are believed to help produce an approximation of these ideals¹²Thompson JK, Stice E. Thin-ideal internalization: Mounting evidence for a new risk factor for body-image disturbance and eating pathology. Current directions in psychological science. 2001;10(5):181-183..

Negative Mood

Eating makes us feel good; it helps us regulate our moods by temporarily blocking out any negative things we may be feeling. Unfortunately, for some people, constant negative mood states can be a major trigger for binge eating and purging behaviours¹³Stice E. Risk and maintenance factors for eating pathology: a meta-analytic review. Psychological Bulletin. 2002;128:825-848..

Developing adaptive emotion regulation strategies is key for preventing eating disorder behaviours.

How do these risk factors work together?

These risk factors form a logical sequence to collectively cause eating disorders.

How do they do this?

Theories of eating disorders propose that perceived socio-cultural pressures to be thin leads to the internalisation of the thin ideal.

This thin-ideal internalisation encourages body dissatisfaction because many women cannot achieve an unrealistically thin figure and are therefore ashamed of themselves and their body.

Body dissatisfaction then causes two other important risk factors: negative affect and dieting. Negative affect arises due to the disappointment and ill-feelings towards one’s body, and dieting is attempted in hope that it will improve one’s appearance.
Both negative affect and dieting then cause eating disorder behaviours (e.g., bingeing, purging etc.), forming a vicious cycle¹⁴Stice E. A prospective test of the dual-pathway model of bulimic pathology: mediating effects of dieting and negative affect. Journal of abnormal psychology. 2001;110(1):124..

Other important psychosocial risk factors

Perfectionism and low self-esteem

Perfectionism (i.e., setting unrealistically high standards of the self) and low self-esteem (i.e., a global negative view of the self) work together to put people at risk for an eating disorder. Often people set such high standards for themselves to manage low self-esteem. They mistakenly believe that if they can meet these high standards, they will have a sense of control and be “successful”. They may strive for perfection in multiple domains, and when people value their weight, shape, and eating, then these two psychological traits can cause people to adopt extreme weight control and eating disorder behaviours¹⁵Fairburn CG. Cognitive behavior therapy and eating disorders. New York, NY: Guilford Press 2008..

Teasing and bullying

Being teased or bullied about one’s weight can put people at risk for an eating disorder. For example, 60% of those with an eating disorder reported that being bullied about their weight contributed to the development of their eating disorder¹⁶Copeland WE, Bulik CM, Zucker N, et al. Does childhood bullying predict eating disorder symptoms? A prospective, longitudinal analysis. International journal of eating disorders. 2015;48(8):1141-1149.. Being teased may cause people to go to extreme lengths (e.g., fasting, compulsive exercise etc.) for weight loss.

Child abuse

There are many reasons why childhood abuse puts people at risk for developing an eating disorder. First, childhood abuse can cause intolerable emotions, so eating disorders can serve as an attempt to regulate these emotions. Second, childhood sexual abuse could lead to a dissociative coping style that is later displayed as binge eating. Third, childhood abuse can also make victims feel that they have no control over their lives, which could lead to self-starvation as a way to re-exert control¹⁷Caslini M, Bartoli F, Crocamo C, et al. Disentangling the association between child abuse and eating disorders: a systematic review and meta-analysis. Psychosomatic medicine. 2016;78(1):79-90..

Protective Factors

It is important to not only consider the factors that place people at risk for an eating disorder but also on the factors that protect against eating disorders.

Focusing on enhancing these protective factors (rather than just reducing the risk factors) is equally important in preventing the onset of eating disorders and eating disorder behaviours.

Individual protective factors

1. High self-esteem
2. Body appreciation
3. Media literacy
4. Academic achievement
5. Problem-solving skills
6. Intuitive eating

Familial protective factors

1. Regular family mealtimes
2. Being in a family that does not overvalue weight and shape
3. A family that offers encouragement and fosters growth
4. Being involved in a family that do not criticize each other

Socio-cultural protective factors

1. Belonging to a society that accepts the breadth of body shapes and sizes
2. A peer network that does not over-emphasise body weight and shape

I hope this has helped you to understand the causes and risk factors for eating disorders.

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