Eating disorder portion of the vulnerability to develop eating disorders can be inherited, and there is evidence to show that there is a genetic locus that shows susceptibility for developing anorexia nervosa. About 60% of eating disorder cases are attributable to biological and genetic components. Other cases are due to external reasons or developmental problems. There are also other neurobiological factors at play tied to emotional reactivity and impulsivity that could lead to binging and purging behaviors. Epigenetics: Epigenetic mechanisms are means by which environmental effects alter gene expression via methods such as DNA methylation; these are independent of and do not
Eating disorder specified feeding or eating disorders. Anxiety disorders, depression, and substance abuse are common among people with eating disorders. These disorders do not include obesity. The cause of eating disorders is not clear. Both biological and environmental factors appear to play a role. Cultural idealization of thinness is believed to contribute. Eating disorders affect about 12 per cent of dancers. Those who have experienced sexual abuse are also more likely to develop eating disorders. Some disorders such as pica and rumination disorder occur more often in people with intellectual disabilities. Only one eating disorder can be diagnosed at a given time.