From NEDC Newsletter 2016
Eating disorders are complex mental illnesses. To date, no single cause has been identified. Rather, widespread research suggests that the onset of an eating disorder is unique to the individual and often involves the integration of multiple factors (Culbert, Racine, & Klump, 2015; Rikani et al., 2013). Understanding these known risk factors has the potential to improve treatment methods, determine high risk groups for prevention programs and reduce stigma (Striegel-moore & Bulik, 2007). Current literature explores genetic, psychological and socio-cultural influences.
Genetic Vulnerability
The genetic link to eating disorders has been a consistent focus in scientific literature. Previous findings from family and twin studies indicate that eating disorders have a hereditary component (Trace, Baker, Pe, & Bulik, 2013). In particular, one study found that first-degree relatives of individuals with Anorexia Nervosa are 11 times more likely to develop the illness than relatives of individuals without the disorder (Strober, Freeman, Lampert, Diamond, & Kaye, 2000). This suggests that genetics can influence an individual’s vulnerability to eating disorders.
The onset of eating disorders, specifically Anorexia Nervosa and Bulimia Nervosa, typically occurs during adolescence (Hudson, Hiripi, Pope, & Kessler, 2007; Striegel-moore & Bulik, 2007). The complex hormonal, physical and neural changes associated with puberty increase the likelihood of adolescent engagement in disordered eating behaviours (Klump, 2013). Given such, puberty is recognised as a significant risk period.
Although there has been decades of research exploring the genetics of eating disorders, the biological causes are still not well understood. This may be because the majority of studies involve small sample sizes and are often conducted during the acute or recovery phase of an eating disorder (Trace et al., 2013). The QIMR Berghofer Medical Research Institute in Queensland are currently undertaking the largest international investigation into the cause of Anorexia Nervosa. This study, known as the Anorexia Nervosa Genetic Initiative (ANGI), seeks to identify the specific genes associated with Anorexia Nervosa in the hopes of better understanding the causes and finding a potential cure.
Psychological Factors
A connection between certain personality traits and eating disorders has been identified. Research into Anorexia Nervosa and Bulimia Nervosa has shown that obsessive compulsive personality disorder, low self -esteem and perfectionism are considerable risk factors for disordered eating behaviours and attitudes (Culbert et al., 2015; Egan, Wade, & Shafran, 2011). A recent investigation into childhood obsessive compulsive personality traits found that the presence of perfectionism and inflexibility in early life can predict the later development of an eating disorder (Southgate, Tchanturia, Collier & Treasure, 2008). Personality types are also important to consider when treating an eating disorder, as obsessive compulsive tendencies may continue to drive restrictive and rigid behaviours. Given such, Egan et al. (2011) argues that traits such as perfectionism should be treated alongside an eating disorder, in order to effectively reduce disordered eating symptoms.
The cognitive, behavioural and interpersonal changes that accompany eating disorders can make it difficult to discern the psychological causes from the psychological effects. For example, the co-existence of depression and anxiety with eating disorders has raised debate as to whether such conditions precede or are a direct outcome of an eating disorder.
Socio-Cultural Influences
Socio-cultural influences play a considerable role in the development of eating disorders. Mass media, such as television, magazines and advertising, airbrush and alter images to portray unrealistic representations of the male and female body (Perloff, 2014; Striegel-moore & Bulik, 2007). Predominant images suggest that beauty is associated with thinness for females and a lean, muscular body for males. Individuals who internalise this ‘thin’ ideal and strive for the ‘perfect’ body, are at a greater risk of developing body dissatisfaction, which can lead to dieting and other disordered eating behaviours (Culbert et al., 2015). More recent research has explored the impact of social media on body image and eating behaviours. Andsager (2014) argues that the introduction of Facebook and Instagram has increased our exposure to photo-shopped images and thin ideals. Although a direct link to eating behaviours is yet to be established, the appearance-focused nature of social media platforms has been shown to cultivate body image concerns and reduce self-esteem (Perloff, 2014).
Additionally, there is growing evidence that the ways in which weight, shape and size are discussed in the home have a strong impact on self-esteem and dieting behaviours (Loth et al., 2014). Culbert et al. (2015) propose that environmental and psychological factors interact with and influence the expression of genes to cause eating disorders. Further research into this relationship is needed.
Modifiable Risk Factors
Identifying potential risk factors for eating disorders is beneficial in shaping effective prevention and early intervention programs. Research indicates that prevention programs with the most favourable outcomes are those which focus on reducing modifiable risk factors (Jacobi, Hayward, Zwaan, Kraemer, & Agras, 2004). Low self-esteem, body dissatisfaction, dieting behaviours and internalisation of the thin ideal have been acknowledged as variable factors associated with the onset of eating disorders.
The aetiology of eating disorders is becoming a growing field of research. Although limited conclusive evidence has been recorded, understanding possible influences can inform best practice and encourage effective management of eating disorders.
References
Andsager, J. L. (2014). Research Directions in Social Media and Body Image. Sex Roles, 71, 407–413.
Culbert, K. M., Racine, S. E., & Klump, K. L. (2015). Research Review : What we have learned about the causes of eating disorders – a synthesis of sociocultural , psychological , and biological research. Journal of Child Psychology and Psychiatry, 11, 1141–1164.
Egan, S. J., Wade, T. D., & Shafran, R. (2011). Perfectionism as a transdiagnostic process : A clinical review. Clinical Psychology Review, 31(2), 203–212.
Hudson, J. I., Hiripi, E., Pope, H. G., & Kessler, R. C. (2007). The Prevalence and Correlates of Eating Disorders in the National Comorbidity Survey Replication. Journal of Biological Psychiatry, 61, 348–358.
Jacobi, C., Hayward, C., Zwaan, M. De, Kraemer, H. C., & Agras, W. S. (2004). Coming to Terms With Risk Factors for Eating Disorders : Application of Risk Terminology and Suggestions for a General Taxonomy. Psychological Bulletin, 130(1), 19–65.
Klump, K. L. (2013). Puberty as a critical risk period for eating disorders : A review of human and animal studies. Hormones and Behavior, 64(2), 399–410.
Loth, K. A., Ph, D., D, R., Maclehose, R., Ph, D., Bucchianeri, M., … D, R. (2014). Predictors of Dieting and Disordered Eating Behaviors From Adolescence to Young Adulthood. Journal of Adolescent Health, 55(5), 705–712.
Perloff, R. M. (2014). Social Media Effects on Young Women ’ s Body Image Concerns : Theoretical Perspectives and an Agenda for Research, 363–377.
Rikani, A. A., Choudhry, Z., Choudhry, A. M., Ikram, H., Asghar, M. W., Kajal, D., … Mobassarah, N. J. (2013). A critique of the literature on etiology of eating disorders. Annals of Neurosciences, 20(4), 157–161.
Southgate, L., Tchanturia, K., Collier, D., & Treasure, J. (2008). The development of the childhood retrospective perfectionism questionnaire (CHIRP) in an eating disorder sample. European Eating Disorders Review, 16(6), 451-462.
Striegel-moore, R. H., & Bulik, C. M. (2007). Risk Factors for Eating Disorders. American Psychologist, 62(3), 181–198.
Strober, M., Freeman, R., Lampert, C., Diamond, J., & Kaye, W. (2000). Controlled family study of anorexia nervosa and bulimia nervosa: Evidence of shared liability and transmission of partial syndromes. The American Journal of Psychiatry, 157(3), 393–401.
Trace, S. E., Baker, J. H., Pe, E., & Bulik, C. M. (2013). The Genetics of Eating Disorders. Annual Review of Clinical Psychology, 9, 589–620.