According to the National Eating Disorders Association, up to 10 million females and 1 million males are suffering from the eating disorders bulimia or anorexia. While it is not entirely clear what causes some people to develop these eating disorders, it is believed that the combination of genetic, hormonal, environmental and sociocultural factors may play a role.
Genetic Factors
There is some evidence to suggest that both bulimia and anorexia may be linked to genetic factors. According to the Mayo Clinic, researchers have identified an area on chromosome 1 that is linked with increased likelihood of developing anorexia. Individuals with a genetic predisposition toward certain personality traits such as perfectionism and sensitivity are also at higher risk, and additional studies show that women with a sister or mother with anorexia are more likely to develop the disorder. Bulimia is also more likely to run in families, according to eMedTV.
Hormonal Factors
According to the University of Maryland Medical Center, studies suggest that a number of biochemical and hormonal abnormalities may underlie anorexia and bulimia. Researchers have found that certain reproductive hormones are abnormally low among individuals with anorexia, and, in up to half of all cases, this hormone deficiency precedes the onset of the eating disorder, suggesting it may be a cause. Individuals with anorexia and bulimia have also been shown to have abnormally high levels of a hormone called ghrelin. This hormone slows the body's metabolism and increases feelings of hunger and may play a causal role, although more research is needed.
According to the Mayo Clinic, additional evidence suggests that anorexia may also be caused by deficiencies in or abnormal function of the neurotransmitter serotonin--a chemical involved in the regulation of mood that has been linked to depression. Both anorexia and bulimia are linked to high levels of the stress hormone cortisol.
Psychological and Personality Factors
The Mayo Clinic reports that low self-esteem, perfectionism and obsessive-compulsive personality traits are commonly found among those with anorexia and may contribute to the development of the eating disorder. Likewise, individuals with bulimia have been found to share traits such as low self-worth, helplessness, extreme fear of becoming fat and distorted body image, according to eMedTV.
Family Environment Factors
Several negative family influences have been implicated as potential causes of anorexia and bulimia, according to the University of Maryland Medical Center. For example, women with bulimia are significantly more likely to have an obese parent, a history of sexual abuse and parents with psychiatric disorders. People with both anorexia and bulimia are more likely to have had parents with an alcoholism or substance abuse problem. Additionally, parents who are overly critical of their child's weight or who consistently urge their children to lose weight have been implicated as potential causes in the development of eating disorders.
Social and Cultural Influence
The overabundance of food in the Western world coupled with our culture's tendency in magazines, television and film to glamorize thinness have been implicated as a potential cause of anorexia and bulimia. As reported by eMedTV, studies indicate that even girls who are of normal weight or below-normal weight report being unhappy with their bodies and engaging in unhealthy behaviors to curb their eating. According to the Mayo Clinic, however, because eating disorders existed prior to these contemporary social, media and cultural influences, it is not believed that these represent a sole cause of eating disorders.
