Eating Disorders - Introduction

Facts associated with anorexia nervosa:

At least 15% to as much as 60% of normal body weight is lost.
The patient with anorexia nervosa has an intense fear of gaining weight, even when he or she is severely underweight.
Individuals with anorexia nervosa have a distorted image of their own weight or shape and deny the serious health consequences of their low weight.
Women with anorexia nervosa miss at least three consecutive periods. (Some experts believe women can be anorexic without this occurrence.)

Patients with this condition are often characterized as anorexia restrictors or anorexic bulimic patients. Each type is equally prevalent.

Anorexia restrictors reduce their weight by severe dieting.
Anorexic bulimic patients maintain emaciation by purging. Although both types are serious, the bulimic type, which imposes additional stress on an undernourished body, is the more damaging.

Severe anorexia is common in the elderly, who may experience weight loss because of social isolation, impaired gastrointestinal function, or loss of certain chemicals related to the feeding drive. Such age-related anorexia, however, is not synonymous with anorexia nervosa, which is a psychologic disorder.

Binge Eating (Binge Eating Disorder)

Bingeing without purging is characterized as compulsive overeating (binge eating) with the absence of bulimic behaviors, such as vomiting or laxative abuse (used to eliminate calories). Binge eating usually leads to becoming overweight.

To be diagnosed as a binge eater, a person typically has the following characteristics:

Bingeing at least twice a week for6 months
Consuming 5,000 to 15,000 calories in one sitting
Eating three meals a day plus frequent snacks
Overeating continually throughout the day, rather than consuming large amounts of food during binges

Since binge eating disorder is generally associated with weight gain, it will not be further discussed in this report. [For more information on bingeing without purging, see In-Depth Report #53: Obesity.]

Eating Disorders Not Otherwise Specified

A fourth category called eating disorders not otherwise specified (NOS) has been established to define eating disorders not specifically defined as anorexia or bulimia. This category includes the following:

Infrequent binge-purge episodes (occurring less than twice a week or having such behavior for less than months)
Repeated chewing and spitting without swallowing large amounts of food
Normal weight and anorexic behavior

Such patients tend to be older at diagnosis. Although less serious than other eating disorders, these patients still face similar health problems, including a higher risk for fractures and other conditions.