Self-imposed Starvation
Anorexia nervosa is self-imposed starvation and starvation can wreak havoc on all the major body systems and organs. While the basic metabolic response to starvation is to conserve calories, in time, the body will start to feed on its own tissue, including both muscles and organs. The liver and intestines lose a high percentage of their total weight during starvation, while the heart and kidneys will lose a moderate amount of weight.
This organ weight loss often leads to permanent damage. When the size of the heart is reduced, for example, its owner will experience low blood pressure and a slowed pulse. This correlation between starvation and organ weight loss can lead to cardiac arrest or kidney failure. In most cases, 8-12 weeks of total starvation is fatal.
The long term dehydration that is associated with anorexia can lead to kidney failure, since the body depends on a certain level of water to keep salt and other minerals in proper balance. Cells and tissues cannot function at their optimal level when the body is not hydrated.
Too Much Exercise
Too much exercise can damage muscles and cartilage, in particular when the workout concentrates on one area of the body for an extended time period.
Anorexics upset the delicate hormonal balance of the body leaving them vulnerable to osteoporosis, or the loss of bone density. Bone growth may be arrested in young anorexics, leading to stunted growth, and bone fractures are more common.
The heart is affected by anorexia in many ways. An irregular or slowed heart rate signifies that the heart muscle is undergoing changes. This may lead to low blood pressure. The lower the blood pressure and heart rate becomes, the greater the risk of heart failure.
When the heart muscle becomes thin or flabby from nutritional deficiency, the result may be heart failure, in particular if the chemical balance of the body cannot be stabilized.
The female body needs fat in order to produce estrogen. When there is not enough estrogen, there will be a cessation of menstruation (amenorrhea), and infertility. In men, testosterone will cease to be produced, resulting in decreased libido (sex drive).
Because the body lacks its layer of insulating fat to warm the body, it will begin to grow fine hair all over. This type of hair growth is called lanugo.
When the body is not supplied with food for its source of energy, it begins to rely on the hormone known as adrenaline, which in normal times is secreted only during times of stress or fear. This causes a state of excitability or hyperactivity.