A disturbed relationship to food marks all eating disorders, as does emotional fragility. Since eating is a normal part of life, these are conditions marked by extremes. All eating disorders may start out unnoticed––a person eats a little more or a little less food than usual. The urge to eat more or less becomes increasingly compelling until it can become the focus of a person's existence.
In anorexia, sufferers dramatically restrict what they eat and are markedly underweight.

Symptoms include:


• refusal to maintain body weight at or above a minimally normal weight for age and height
• intense fear of gaining weight or becoming fat
• extreme influence of body weight or shape on self-evaluation
• infrequent or absent menstrual periods in those who have reached puberty
• use of either food restriction or excessive exercising to limit body weight
• feeling cold or lethargic, due to drop in body temperature as weight loss progresses
• growth of hair all over the body
• dry yellowish skin
• brittle hair and nails
• severe constipation.


In bulimia, periods of food restriction are punctuated by bouts of binge-eating and some compensatory behavior, usually purging. As a result, sufferers may appear to be normal weight. Symptoms of bulimia include:
• recurrent episodes of binge-eating, characterized by consuming in a short amount of time an amount of food larger than most people would eat
• during those binge-eating bouts, a feeling that one cannot stop eating or control how much one eats
• some compensatory behavior to prevent weight gain; purging is most common, but laxative use and excessive exercising are also widely used
• extreme influence of body weight or shape on self-evaluation
• chronically inflamed sore throat
• swollen glands in the neck or jaw
• wearing of tooth enamel and frank decay as a result of exposure to stomach acids
• dehydration due to purging of fluids
• kidney problems from diuretic abuse.


By contrast, binge-eating disorder is marked by recurrent episodes of extreme overeating not accompanied by compensatory behavior, so those with the disorder are usually overweight to obese. Symptoms include:
• eating much more rapidly than normal
• eating until feeling uncomfortably full
• eating large amounts of food even when not hungry
• eating alone because of shame or embarrassment over eating behavior
• binge-eating occurs at least two days a week for six months or more.