An eating disorder character- ized by extreme attempts to control the diet and/or an aversion to food. It affects young women most often, but it may also be seen in men, children, and older adults. Symptoms can include extreme weight loss, weakness, and dulling of hair and skin. In some cases, anorexia nervosa may be a form of obsessive-compulsive disorder. Treatment includes medication, therapy, dietary counseling and, in extreme cases, hospitalization. Untreated anorexia can cause organ failure and death.