Anorexia nervosa does not have a single cause, but is related to many different factors. These factors are sometimes divided into predisposing, precipitating and perpetuating factors, which make a person vulnerable to developing, triggering the onset and maintaining the eating disorder, respectively. Anorexia nervosa often starts as a simple diet to get fit or eat healthier, but progresses to extreme and unhealthy weight loss. Social attitudes toward bodily appearance, family influences, genetics, neurochemical and developmental factors may contribute to the development and maintenance of anorexia nervosa.
It's common to have a personal or family history of anxiety, depression, or obsessive-compulsive habits. Although families in which anorexia nervosa occurs were once labeled as having difficulty with conflict resolution, rigidity, intrusion and overprotection, it is now clear that parents do not cause eating disorders. Research suggests that certain areas of the brain work differently with an active eating disorder. There are similarities and sociodemographic and psychodynamic differences between four subgroups of women with eating disorders who seek outpatient consultations for anorexia nervosa and bulimia.