This post is by guest blogger Anna Fialkowska
Although eating disorders are often considered as “modern” disorders, there is some evidence that pathological patterns of eating date back several centuries (Silverman, 1997). Greek physician Galen made a reference to the syndrome of overeating and vomiting named as bulimos as early as the second century (Ziolko, 1996). Nevertheless, it was not until the 1970s-1980s that eating disorders began to attract the attention of clinicians who started seeing more and more patients with pathological eating patterns. The prevalence of eating disturbances has been increasing significantly since then and it is estimated that about 700,000 people in the UK suffer from an eating disorder. According to a current systematic review, the lifetime prevalence of those with an eating disorder is 8.4% for women and 2.2% for men. A typical eating disorder, followed by binge eating and bulimia nervosa were shown to be the most common eating disorders. Anorexia nervosa was revealed to be the least common (Galmiche, 2019). However, anorexia nervosa has the highest mortality rate of any psychiatric disorder, standing at 12 times higher than the mortality rate for females aged 15 to 24 in the general population. It is estimated that one in five deaths among individuals with anorexia is due to suicide (Arcelus et al., 2011). Furthermore, the risk of suicide is 50 times greater than in the general population, which reveals the urgency to increase awareness and tackle disorders which are unquestionably mortal. Even though the prevalence of eating disorders is significantly increasing, there is a high chance that the statistics are gross underestimations due to a high number of those who do not present to health services remaining underdiagnosed.
Aetiology & risk factors
General factors
Eating disorders can develop at any age but the risk of onset is significantly increased in adolescents and young adults. Additionally, females were shown to be more likely to develop pathological eating patterns in comparison to men, with 90% of those diagnosed being female. There are some discrepancies between the studies however, with some showing that that there are three females for every male with eating disorder (Jones & Morgan, 2010) and others suggesting that men may be underdiagnosed due to stereotypes of eating disorders as a “female disorder”. Additionally, the gender bias within the DSM criteria notes that women are more likely to have a drive for thinness and dieting than males and this can lead to further discrepancies. Body dissatisfaction among men is also usually driven by a desire to be muscular over being thin. Therefore, over-exercising and dietary obsessions are more likely to be observed among men compared to other ways of controlling weight, such as vomiting. This can lead to lower awareness among men and a higher likelihood of being misdiagnosed (Jones & Morgan, 2010).
In addition to the above, homosexuality has been shown to be one of the main risk factors for eating disorders among men. Gay and bisexual men have much higher rates of eating disorders in comparison to heterosexual men (Feldman & Meyer, 2007). This can be associated with lower body-esteem, a higher drive for thinness and attractiveness found among gay men (Smith et al., 2011). Other groups of men who are at increased risk of eating disorders are wrestlers and jockeys, who need to maintain a specific weight in order to compete or work (Carlat et al., 1997)
Neurobiological factors
Abnormalities within neurotransmitter activity, including serotonin and dopamine, have also been associated with eating disorders. A high number of patients with eating disorders have been shown to respond well to treatment with antidepressants that target serotonin. This has led to a conclusion that the serotonergic system of patients with pathological eating patterns can be disrupted (Bailer & Kayne, 2011). There is also some evidence that patients with anorexia nervosa have lower levels of 5-HIAA, which is a major metabolite of serotonin. Nevertheless, it is not clear if the abnormal neurotransmitter activity is involved in the development of eating disorders or they are caused by physiological alterations due to malnutrition.
Psychosocial factors
There are various psychological factors predisposing individuals to the development of eating abnormalities, such as symptoms of anxiety, depression, low self-esteem and perfectionism, with the latter linked heavily with anorexia nervosa and bulimia. One study has shown that individuals with anorexia, regardless of type (purging or restricting), had higher scores on perfectionism than individuals without eating abnormalities (Halmi et al., 2000). The same trend has been observed among patients with bulimia (Anderluh et al., 2003). Speculation exists suggesting that personality changes could be a result of eating problems as opposed to be the cause. However, if this were the case, we would expect to see a reduction in perfectionism after recovery. Yet, this has not been observed in most studies (Bardone-Cone et al., 2007). Interestingly, the research suggests that men with eating disorders are less perfectionistic than women with eating disorders, which can provide a potential explanation of why there is a lower likelihood of suffering from eating distortions amongst men (Woodside et a., 2004).
Family history of an eating disorder
Another risk factor is family history of eating disorders. The risk of eating disorders was shown to be 7-12 times higher in individuals with a family history of pathological eating patterns. Additionally, Mangweth and colleagues (2003) revealed that the relatives of patients with eating disorders were more likely to suffer from other psychological complications such as depression, obsessive compulsive disorder and alcohol or drug dependency. Although family studies are a highly valuable source of information, it is problematic to distinguish the impact of genetic and environmental factors leading to pathology for a number of reasons. To distinguish genetic and environmental influences, twin studies have been carried out which suggest that anorexia nervosa and bulimia can both be heritable disorders (Wade, 2010; Fairburn & Harrison, 2003). However, findings from other twin studies are conflicting, revealing estimated heritability between 33-84% for anorexia, 28-83% for bulimia, or no correlation at all. The findings suggest that the importance of genetic and environmental factors should not be underestimated and that both factors play a significant role in the aetiology of both conditions.
Conclusions
As has been shown, the aetiology of eating disorders is highly debatable. There are various factors that can increase the risk of eating pathology, including genetic and environmental influences. To fully comprehend the development of abnormal eating patterns, we should explore the genetic predispositions and also the environment that the individual lives in to fully understand the cause. There is no doubt that a western culture promoting ‘unattainable thinness’ is a powerful socioeconomic background from which most of the anorexic women appear to come (McClelland & Crisp, 2001). However, eating disorders are simply one example of psychological disorders that are highly complex and require examination of multiple factors to really understand them. Treatments can be highly successful with the right understanding, and therapies such as CBT have shown great promise in supporting those with eating disorders. However, providing a more positive culture for young adults to grow up in may be a better place to start in the prevention of eating disorders instead of their treatment.
About Anna Fialkowska
Anna Fialkowska is a Trainee Health Psychologist, is completing her doctoral training at the University of the West of England and currently works as a Heath Improvement Practitioner. She has worked within the field of mental health dysfunction and cognitive rehabilitation over the last six years. Her main areas of research include the development of behaviour change interventions, the impact of stress on individuals’ physical health and the effect of chronic conditions on psychological well-being.
References:
- Arcelus, J., et al., (2011). Mortality rates in patients with anorexia nervosa and other eating disorders. Archives of General Psychiatry, 68 (7), 724-731
- Bailer, U.F., & Kayne, W.H. (2011). Serotonin: Imagining findings in eating disorders. Current Topics in Behavioural Neuroscience, 6, 59-79
- Bardone-Cone, A.M, et al., (2007). Perfectionism and Eating Disorders: Current status and future directions. Clinical Psychological Review. 26, 384-405
- Fairburn & Harrison, (2003). Eating Disorders. Lancet, 261, 407-416
- Feldman & Meyer, (2007). Eating Disorders in diverse lesbian, gay and bisexual populations. International Journal of Eating Disorder, 40, 218-226
- Halmi et al., (2000). Perfectionism in Anorexia nervosa. Variation by clinical subtype, obsessionality and pathological eating behaviour, American Journal of Psychiatry, 157 (11), 1799-1805
- Jones, W. R., & Morgan, J. F. (2010). Eating disorders in men: A review of the literature. Journal of Public Mental Health, 9(2), 23–31
- McClelland, L. and Crisp, A. (2001), Anorexia nervosa and social class. International. Journal of. Eating Disorders, 29, 150-156
- Smith et al., (2011). Muscularity versus leanness: An examination of body ideals and predictors of disordered eating in heterosexual and gay college students. Body Image, 8,232-36
- Wade, T.D. (2010). Genetic influences on eating and the eating disorders. The Oxford Handbook of Eating Disorders. New York: Oxford University Press
- Woodside D.B., et a., (2004). Personality in men with eating disorders. Journal of Psychosomatic Research, 57, 273-278
- Ziolko, H.U. (1996). Bulimia: A historical outline. International Journal of Eating Disorders, 20, 345-358