Anorexia nervosa is characterized by not weighing a lot.
Anorexia nervosa , often referred to simply as anorexia , is an eating disorder characterized by a low weight , fear of gaining weight , a strong desire to be thin , and food restriction . Many people with anorexia see themselves as overweight even though they are in fact underweight . Often they weigh themselves frequently , eat only small amounts , and only eat certain foods . The diagnosis requires a significantly low weight .