What causes an eating disorder?
The factors that contribute to the onset of an eating disorder are complex. No single cause of eating disorders has been identified; however, known contributing risk factors include:
- Genetic vulnerability
- Psychological factors
- Socio-cultural influences
There is some evidence that eating disorders have a genetic basis. It has been shown that this genetic influence is not simply due to the inheritance of any one gene but results from a much more complicated interaction between many genes and quite possibly non inherited genetic factors as well.
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.
Research into Anorexia Nervosa and Bulimia Nervosa specifically, has identified a number of personality traits that may be present before, during, and after recovery from an eating disorder.
- negative emotionality
- harm avoidance
- core low self-esteem
- traits associated with avoidant personality disorder
It is important to include that prolonged starvation induces change in cognition, behaviour, and interpersonal characteristics. It can therefore be difficult to discern the psychological causes from the psychological effects of eating disorders. 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.
Evidence shows that socio-cultural influences play a role in the development of eating disorders.The most predominant images in our culture today suggest that beauty is equated with thinness for females and a lean, muscular body for males. People who internalise this ‘thin ideal’ have a greater risk of developing body dissatisfaction which can lead to eating disorder behaviours.
The introduction of social media, particularly 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.
Modifiable risk factors
It is possible to change some socio-cultural, psychological and environmental risk factors. The modifiable risk factors for eating disorders are identified as:
- Low self-esteem
- Body dissatisfaction
- Internalisation of the thin socio-cultural ideal
- Extreme weight loss behaviours
Extreme weight loss behaviours
Disordered eating is the most common indicator of an eating disorder onset. Disordered eating is a disturbed pattern of eating that can include fasting and skipping meals, eliminating food groups, restrictive dieting accompanied by binge eating and excessive exercise. Compensatory behaviours may also be present, such as laxative abuse and self-induced vomiting.
Disordered eating can result in significant mental, physical and social impairment and is associated with not only eating disorders but also health concerns such as depression, anxiety, nutritional and metabolic problems and weight gain.
While moderate changes in diet and exercise have been shown to be safe, significant mental and physical consequences may occur with extreme or unhealthy dieting practices.
Dieting is associated with eating disorders and other health concerns including depression, anxiety, nutritional and metabolic problems, and, contrary to expectation, with an increase in weight.
Dieting and adolescents at risk
Puberty is a time of great change biologically, physically and psychologically. Teenagers are vulnerable to societal pressures and can often feel insecure and self conscious, factors that increase the risk of engaging in extreme dieting behaviour.
Research shows that young people who engage in unhealthy dieting practices are almost three times as likely as their healthy-dieting peers to score high on measures assessing suicide risk.
Studies in Australia and New Zealand have found:
- Approximately half of adolescent girls have tried to lose weight and practise extreme weight loss behaviours such as fasting, self-induced vomiting and smoking
- As many as 75% of high school girls feel fat or want to lose weight
- Young people who diet moderately are six times more likely to develop an eating disorder; those who are severe dieters have an 18-fold risk
- Among girls who dieted, the risk of obesity is greater than for non-dieters