According to the American Psychiatric Association, symptoms of anorexia nervosa include:
- Resistance to maintaining body weight at or above a minimally normal weight for a person's age and height.
- Intense and unrealistic fear of gaining weight or becoming fat, even though a person is underweight.
- Disturbance in the way one's body weight or shape is experienced, undue influence of body weight or shape on self-esteem, or denial of the seriousness of the current low body weight.
- Infrequent or absent menstrual periods in women who have reached puberty.
Anorexia nervosa sufferers are often obsessed with food and develop habits such as avoiding food and meals, selecting a few foods and eating these in small quantities, or carefully weighing and portioning food. A person with anorexia may repeatedly weigh himself or herself and, when looking in a mirror, see an overweight person even though he or she may in reality be abnormally thin. Anorexics may also use other weight loss techniques such as intense and compulsive exercise or purging by means of vomiting or abusing laxatives, enemas, or diuretics.
In the long run, anorexics may starve themselves to the point where their bodies are denied the essential nutrients they need to function normally. When the body slows down all of its processes in order to conserve energy, some of these serious medical consequences may result:
- Abnormally slow heart rate and low blood pressure, which mean that the heart muscle is changing. The risk for heart failure rises as the heart rate and blood pressure levels sink lower and lower.
- Reduction of bone density (osteoporosis), which results in dry, brittle bones.
- Muscle loss and weakness.
- Severe dehydration, which can result in kidney failure.
- Fainting, fatigue, and overall weakness.
- Dry hair and skin. Hair loss is common.
- Growth of a downy layer of hair called lanugo all over the body, including the face, in an effort to keep the body warm.
- Recurrent episodes of binge eating, characterized by eating an excessive amount of food within a discrete period of time and by a sense of lack of control over eating during the episode.
- Recurrent, inappropriate compensatory behavior in order to prevent weight gain, such as self-induced vomiting or misuse of laxatives, enemas, diuretics, or other medications, fasting, or excessive exercise.
- Electrolyte imbalances that can lead to irregular heartbeats and possibly heart failure and death. Electrolyte imbalance is caused by dehydration and loss of potassium and sodium from the body as a result of purging behaviors.
- Potential for gastric rupture during periods of binging.
- Inflammation and possible rupture of the esophagus from frequent vomiting.
- Tooth decay and staining from stomach acids released during frequent vomiting.
- Chronic irregular bowel movements and constipation as a result of laxative abuse.
- Peptic ulcers and pancreatitis.
- High blood pressure.
- High cholesterol levels.
- Heart disease as a result of elevated triglyceride levels.
- Secondary diabetes.
- Gallbladder disease.