The prevalence of eating disorders has increased in recent years. Preoccupation with weight and exercise management among women is particularly evident on university campuses. It is estimated that approximately 5% of the adolescent and young adult female population suffer from eating disorders. Although a complete picture of the etiology of eating disorders does not exist, researchers generally seem to agree that the onset of this disorder is the result of a combination of psychological, cultural, family, developmental, and biological factors (Kamata, 2003).
The medical and social problems identified with eating disorders can be manifested in many ways. Eating disorders may decrease longevity, aggravate the onset and clinical progression of maladies, and modify the social or economic quality of life. On the positive side, weight loss can reverse all or most of the disadvantages of obesity.
Physiology of Weight Change
Weight loss and gain provoke a series of physiological responses. The process of weight loss has been studied extensively in both obesity and anorexia. At first glance, the effects of weight loss in these two areas would seem much different because the anorexic starts at a normal weight and gradually becomes emaciated, while the obese person is simply attempting to achieve what they think is a normal weight. However, if one considers that the body may regulate its weight around a point or range, weight loss in an anorexic and an obese person may provoke similar responses if they are regulating at different points. An obese person, for example, may weigh 40 pounds more than "ideal" weight, which may be determined by the size and number of fat cells. Weight loss below this defended level could produce changes (e.g., decline in resting metabolism) similar to those that occur during weight loss in anorexia............
