Anorexia nervosa is an eating disorder in which a
person refuses to maintain a healthy weight for
his or her age and height. It is a self-imposed
starvation resulting from a distorted body image.
The individual typically loses 25% or more of his
or her original body weight.

People with anorexia nervosa have an overwhelming
fear of obesity. They see themselves as fat, even
when they are malnourished. They will deny hunger,
even when they are starving. Body protein and fat
stores become depleted.

Individuals with anorexia often have the following
characteristics:
* behavior that isolates them from others
* excessive dependency needs
* flat affect, or a face that
doesn't display normal emotions
* immaturity
* obsessive-compulsive behavior
* tendency toward an excess of exercise or
other physical activity

The malnutrition caused by anorexia can affect many
body systems. Some common symptoms of anorexia
nervosa include:
* amenorrhea, or absence of menstruation
* arrhythmias, or irregular heartbeats
* constipation
* delayed puberty
* difficulty concentrating, apathy, or irritability
* fatigue
* slow pulse and low blood pressure that
can cause fainting

The exact cause of anorexia nervosa is unknown. It
is believed to be a result of psychological,
biological, and social stress. It may be related
to sexual development during adolescence. Some
experts believe that anorexia nervosa is a
response to social attitudes that equate beauty
with being thin. There is also evidence that
anorexia nervosa runs in families and can be inherited.

Five to 10% of the individuals with diagnosed anorexia
die from the condition. It can cause dehydration,
malnutrition, and salt imbalances. It can affect
the brain and muscles. It may also affect the
reproductive tract, bowels, stomach, and other
body organs. It can cause serious heart problems,
including: · arrhythmias · congestive heart
failure · sudden cardiac arrest and death