The causes of anorexia nervosa are not clear, but experts believe biological and environmental factors, such as conflict between family members, and the current culture of being slim and popularity of dieting contribute to the illness.

Most anorexia nervosa patients are children and young adults ranging in age from 13 to 25. They also tend to have personality traits, such as a tendency toward tidiness, a strong sense of responsibility, of being sensitive and shy, and an often-warped self-image. About 90 to 95 percent of the patients are female.

Low body weight, inappropriate eating habits and obsessions with having a skinny figure are symptoms of anorexia nervosa. Patients are fearful of even the slightest weight gain, and usually engage in frequent and strenuous exercise.

Typical symptoms include dramatic weight loss, an insistence on dieting despite being thin, depression, solitude, fatigue, swollen joints, and an unusual preoccupation with food, recipes and cooking coupled with a refusal to eat.

Anorexia nervosa patients usually have comorbid disorders, such as depression, obsessive-compulsive disorders, and physical complications in almost every major organ. If it happens during adolescence, the disorder may retard physical development.

Puberty may also be a trigger of anorexia nervosa, especially when the adolescent finds the sexual changes in the body shameful, and are not prepared mentally.

Patients are treated with medication, psychotherapy sessions and nutrition supervision in severe malnutrition cases. Family support is very important, but healthy eating habits are also equally important.