Anorexia Nervosa and Bulimia Nervosa

These two psychiatric conditions involve disturbed eating behavior that may cause irreversible damage to the heart, bones, and teeth and may be life-threatening. Women with these conditions are preoccupied with food and body weight, have poor self-esteem and a distorted body image, and often exercise excessively. Many women alternate between anorexia and bulimia throughout the course of their illness. About half of all people with anorexia develop symptoms of bulimia, and about half of all people with bulimia have histories of anorexia or eventually develop symptoms of anorexia.

What is anorexia nervosa?

People with anorexia have an intense fear of becoming fat and purposely lose weight to the point of starvation. A distorted body image leads anorectic women to perceive themselves as grossly obese despite protruding ribs, sunken cheeks, and the evidence on the scale. Although women with anorexia weigh 85 percent or less of the amount expected for their height and stop menstruating (see amenorrhea) because they lack a critical amount of body fat, they vehemently deny that they are underweight. To lose weight, an anorectic woman may severely restrict the amount of food she eats, and she may use self-induced vomiting or laxatives to purge her system of unwanted calories.

Approximately 5 to 10 percent of people with anorexia die as a result of either starvation or suicide. Most of these deaths are sudden and are probably due to cardiac arrhythmias (irregular heartbeats; see arrhythmia), although some may also be due to coma caused by low blood sugar. Chances of death are highest in anorectic women who lose more than 30 percent of their original weight and in those who rely on purges to enhance their weight loss.

What is bulimia nervosa?

Bulimia nervosa shares many features with anorexia. In bulimia, however, there is no obvious emaciation to signal an eating disorder to the world. Unlike the anorectic, the woman with bulimia is aware that she has a problem but feels compelled to conceal it. People with this condition repeatedly go on eating binges in which they eat vast quantities of food without being able to stop. A person with true bulimia has an eating binge at least twice weekly for 3 months, and some bulimic women repeat these binges as often as several times a day. This fills the bulimic woman with shame, because in general she fears losing control over her eating behavior.

Thus, once the binge is over, she regains control over her body by ridding her system of the excess calories. Some bulimic women do this by inducing vomiting, either by sticking their fingers down their throat or by taking emetic drugs. Others use laxatives or diuretics. Still other bulimic women may follow a binge with a fast or a period of vigorous exercise. Whatever method is used, the result may be frequent fluctuations in weight but not the kind of severe weight loss seen in anorexia.

The long-term effects of bulimia are less well known than those of anorexia, partly because so many cases of bulimia are successfully hidden. What is known is that the short-term outlook is often fairly good. As many as 7 in 10 patients completing outpatient treatment programs show substantial improvement, although about a quarter relapse within the next 6 months.

Who is likely to develop anorexia or bulimia?

Over 90 percent of people affected by anorexia and bulimia are women, and most of them are white. Anorexia and bulimia are relatively rare problems among African American women and other ethnic minority groups, especially those who have newly immigrated to this country.

Approximately 0.5 to 1 percent of women between the ages of 15 and 30 have anorexia, and 1 to 3 percent of adolescent and college-age women have bulimia. In addition to these clinically recognized conditions, there is a virtual epidemic of “subclinical” eating disorders among American women, many of whom do not meet the strict criteria for anorexia or bulimia but who are nonetheless preoccupied with food and weight. Many of these women diet obsessively and use techniques associated with anorexia and bulimia—such as binging, purging, and fasting, or abusing laxatives, diet pills, and diuretics—to keep their weight under control.

That women account for over 90 percent of the cases of eating disorders is hardly surprising. The culture's emphasis on slenderness in women and their consequent obsession with weight are well known. Eating disorders are rare in cultures where food is scarce or leanness in women is not highly valued. Even in the United States there are ethnic differences in body image and desirable weight. African American women in general do not seem to be as obsessed with thinness as white women are. In a recent survey of teenage girls, 90 percent of white girls said they were dissatisfied with their bodies, and 62 percent had dieted within the past year. Among black teenagers, by contrast, 70 percent said they were satisfied with their bodies, and 64 percent said that it was better to be a little overweight than underweight.

Women have more trouble losing weight than men because they tend to have a higher percentage of body fat to begin with. A healthy woman has as much as 20 to 30 percent body fat, whereas a healthy man has only about 10 to 15 percent. Throughout most of human history this difference gave women a biological advantage during times of famine by allowing them to store the energy needed for pregnancy and breastfeeding. Today, however, it means that men burn calories faster than women and that overweight men tend to lose weight more easily than overweight women. This biological difference accounts in part for women's obsession with diets and weight loss.

There has been a great deal of speculation about just what other factors—besides a cultural emphasis on thinness and the difficulty women have losing pounds—prompt some women to develop eating disorders while other women manage to avoid them. One factor is occupational: eating disorders are common in women whose livelihood depends on thinness or appearance—for example, dancers, models, actresses, gymnasts, figure skaters, long-distance runners, and jockeys. Anorexia and bulimia are also found in young women, many of whom are discovering that their looks are connected with social acceptance and popularity. Most eating disorders begin in adolescence or young adulthood, with peak incidences occurring between 14 and 18, and a girl's genetic makeup, biology, family background, and psychology, as well as ethnicity, play a role in her vulnerability.

Some researchers have proposed that anorectic girls may lose weight in order to deny their sexuality or to avoid adulthood and independence (that is, by way of a regression to a boyish figure and lack of menstrual periods). Others have proposed that girls whose parents don't let them develop their own identities are more likely to develop anorexia as well. Still other researchers have observed that many women with eating disorders are overachievers with high expectations for themselves (and high expectations from parents) and that they have a deep-seated need to control all aspects of their lives. Some evidence even suggests that the tendency to become anorectic may be partially inherited or that some neurological or hormonal imbalance may be involved, though whether this is the cause or the result of the eating disorder is unclear.

Being obese or even slightly overweight can predispose a woman to developing an eating disorder. In almost all cases, women prone to eating disorders begin with a dissatisfaction about body shape which leads to dieting and then malnutrition. It is not uncommon for a young woman to embark on a diet to lose a few pounds only to find herself several months later hospitalized for serious emaciation. This may be due in part to certain physical and psychological consequences of starvation which perpetuate eating disorders. People who have agreed to be starved experimentally have developed many of the symptoms of an eating disorder—including a preoccupation with food, social withdrawal, loss of sex drive, and depression. Experimentally starved people also often binge temporarily when they are at last offered food.

Finally, people who have been through certain emotional and psychological experiences seem particularly likely to develop eating disorders. For example, the onset of eating disorders often coincides with a stressful event such as leaving home or losing a loved one through illness, death, or divorce. Many women with eating disorders suffer from depression or have family members who suffer from depression, although it is still not clear whether the depression is a result or a cause of the eating disorder. About 10 percent of people with anorexia have obsessive-compulsive disorder, and about half of all people with anorexia and bulimia report having a history of sexual abuse. Anxiety disorders, chemical dependency, and impulsive behaviors such as overspending, shoplifting, sexual promiscuity, substance abuse, and self-mutilation are common in people suffering from bulimia.

What are the symptoms?

Beyond their striking emaciation, many people with anorexia have no obvious symptoms. There are certain attitudes and behaviors that characterize the illness, however. Unlike people who have lost weight or are starving as a result of a medical illness, anorectic women are often proud of their weight loss and complain that they need to lose even more weight. Most anorectic women are physically restless, and some exercise. Obsessed with food, an anorectic may delight in cooking high-calorie treats for family members while abstaining from them herself.

As malnutrition progresses, certain physical symptoms begin to appear, including fatigue, difficulty sleeping, and abdominal discomfort and bloating after eating. Skin often becomes dry, pale, or yellowed, and fine downy hair (lanugo) may grow extensively over the face and arms. Anemia and a low level of white blood cells are common, as are increased blood levels of cholesterol and carotene, a building block for vitamin A.

Other changes reflect the body's response to starvation. Fat stores are depleted, and then skeletal and heart muscles begin to waste away. The metabolism of thyroid hormone changes, slowing the body's metabolism in general and generating symptoms suggestive of hypothyroidism, including intolerance to cold, slowed heartbeat, dry skin, and constipation. Blood pressure may fall, urination may be copious, and lifethreatening cardiac arrhythmias may develop, sometimes resulting in sudden death.

Women with anorexia stop menstruating, often before much weight has been lost, and this amenorrhea may persist even after weight is regained, resulting in infertility. In girls who have not yet reached puberty, skeletal growth, physical development, and sexual maturation come to a halt. Unlike many other changes of anorexia, which can be reversed once body weight is restored, a young girl whose bone growth has been halted may never reach her previously anticipated height. Women with anorexia lose a significant amount of bone mass, increasing their risk of bone fracture. Even after they regain weight, bone density continues to be reduced. As a result, any woman who has had anorexia is at risk for developing osteoporosis later in life even if she manages to avoid it in her 20s, which many do not.

Anorectic women who purge may develop other symptoms depending on the mode of purging (self-induced vomiting, laxatives, emetics, or diuretics). These symptoms are also characteristic of bulimia, and result primarily from purging and not from binge eating itself. Chronic vomiting, for example, can lead to irritation, bleeding, and sometimes even tears of the stomach and esophagus, as well as heartburn and swelling of the salivary glands. It can also lead to symptoms of dehydration (such as dizziness, faintness, and thirst) and of electrolyte imbalance (such as muscle cramps and weakness, prickling sensations, copious urination, palpitations, and abnormalities in the heart's electrical activity). Repeatedly exposing teeth to stomach acids can decalcify enamel and lead to irreversible dental erosion. Women who induce vomiting with their fingers may develop characteristic teeth marks on the upper surface of their hands. Abusing ipecac to induce vomiting sometimes can lead to muscle damage and potentially fatal heart damage.

Abusing diuretics or laxatives, particularly stimulant laxatives, can also result in fluid depletion, electrolyte imbalances, and associated symptoms. Other common symptoms of laxative abuse are abdominal cramps, watery diarrhea, and rectal bleeding or prolapse (in which the rectal wall bulges into the back of the vagina because of weakened pelvic muscles). Bowel function usually returns to normal once laxative use stops, although in rare cases chronic laxative abuse can result in a “cathartic colon” that cannot produce bowel movements without stimulation.

For reasons not fully understood, many women with bulimia develop menstrual irregularities or amenorrhea even though they are not underweight.

How are anorexia and bulimia evaluated?

Anorexia is much easier to diagnose than bulimia because the evidence for it is much more obvious. Although anorectic women themselves deny that they have a problem, it is not unusual for them to be brought in for medical attention by a family member. Also, a clinician will probably suspect an eating disorder in any woman with an unexplained weight loss.

To evaluate the condition, the clinician will question the patient about her attitude toward body shape, weight loss, desired weight, and eating and exercise habits, and will often ask her to record the foods eaten over the past 24 hours. Other questions will concern previous weight loss and diets, menstrual history, symptoms of malnutrition, dehydration, and electrolyte imbalance, as well as use of laxatives, diet pills, vomiting, and emetics. A physical examination and various blood tests and other laboratory studies will be done to rule out other possible causes of weight loss and to determine the severity of malnutrition and dehydration.

The procedure is similar if a clinician suspects that the problem may be bulimia, although this eating disorder often escapes detection. A clinician may suspect it in a woman who is preoccupied with weight and food or has a history of frequent weight fluctuations. Other hints are the patient's complaints about symptoms that result from dehydration or electrolyte imbalance or certain telltale signs such as enlarged salivary glands, erosion of dental enamel, or scars on the top of the hand that has been used to induce vomiting. Some women who would be ashamed to volunteer that they have a problem will reluctantly admit that they need help if asked directly.

How are anorexia and bulimia treated?

Treating eating disorders is often a challenge because so many people with anorexia and bulimia deny that they have a problem—and often behave angrily or manipulatively toward those trying to help them. In addition, a successful treatment program not only has to help the patient regain weight and overcome the consequences of malnutrition but also must help her learn to control her abnormal eating behavior and prevent relapse by addressing underlying psychological and family problems. The best way to accomplish all of these goals is a multidisciplinary treatment approach involving a team of clinicians who together can address the medical, nutritional, and psychological aspects of eating disorders.

When it comes to anorexia, this treatment often must take place in a hospital setting—ideally in a psychiatric unit that specializes in treating eating disorders and can monitor any medical problems that develop in the course of treatment. Usually patients can be induced to gain weight with a normal diet, although sometimes they must first be force-fed through an intravenous line or a nasogastric tube. Patients hospitalized for the treatment of anorexia will also be offered psychotherapy, including family therapy (if relevant) and behavioral therapy to suggest more positive ways to achieve weight goals. Many hospitals offer supervised exercise programs as well. There is still no evidence that drugs—even antidepressants in depressed patients—are dramatically effective in treating anorexia, although fluoxetine (Prozac) may help maintain weight gain once it has occurred.

Usually patients are hospitalized until they reach a normal weight, although some anorectic women can gain weight on their own if they have close medical supervision. This is particularly true for those who have relatively few symptoms, who are highly motivated to change, and who have a strong support network at home.

Some women may recover after a single episode of anorexia, though more than half of the others repeatedly relapse or remain chronically underweight. Even after recovery many women remain preoccupied with their weight and still have unusual eating patterns and psychosocial problems. As many as 40 percent of anorectic women develop bulimia, and 15 to 25 percent develop chronic anorexia. The more weight a woman has lost, the older she is, and the longer her symptoms have lasted, the less likely she is to recover fully. Women who have coexisting bulimia are also more likely to have persistent problems.

Bulimia is usually treated on an outpatient basis with some form of psychotherapy. Although there is still limited understanding about which type of therapy works best, evidence to date supports the use of cognitive-behavioral therapy. The behavioral component helps patients monitor and change their eating behavior, and the cognitive component helps them change their attitudes toward weight and eating. In some cases bulimia can also be treated with group or family therapy, and many women with bulimia find that support groups (such as Overeaters Anonymous) can be helpful as well. Any substance abuse problem that coexists with the bulimia must be treated at the same time.

These psychological treatments are often supplemented with antidepressant medications, which seem to reduce symptoms of bulimia even in bulimic women who do not have symptoms of depression per se. Among the drugs effective in decreasing the frequency of binge eating and purging are tricyclic agents (imipramine and desipramine), trazodone (Desyrel), fluoxetine (Prozac), and monoamine oxidase inhibitors (phenelzine and isocarboxazid).