What causes anorexia nervosa?
At this time, no definite cause of anorexia nervosa has been determined. However, research within the medical and psychological fields continues to explore possible causes.
Studies suggest that a genetic (inherited) component may play a more significant role in determining a person's susceptibility to anorexia than was previously thought. Researchers are attempting to identify the particular gene or genes that might affect a person's tendency to develop this disorder, and preliminary studies suggest that a gene located at chromosome 1p seems to be involved in determining a person's susceptibility to anorexia nervosa.
Other evidence had pinpointed a dysfunction in the part of the brain called the hypothalamus (which regulates certain metabolic processes), as contributing to the development of anorexia. Other studies have suggested that imbalances in neurotransmitter (brain chemicals involved in signaling and regulatory processes) levels in the brain may occur in people suffering from anorexia.
Feeding problems as an infant, a general history of under-eating, and maternal depressive symptoms tend to be risk factors for developing anorexia. Other personal characteristics that can predispose an individual to the development of anorexia include a high level of negative feelings and perfectionism. For many individuals with anorexia, the destructive cycle begins with the pressure to be thin and attractive. A poor self-image compounds the problem. People who suffer from any eating disorder are more likely than others to have been the victim of childhood abuse.
While some professionals remain of the opinion that family discord and high demands from parents can put a person at risk for developing this disorder, the increasing evidence against the idea that families cause anorexia has mounted to such an extent that professional mental-health organizations no longer ascribe to that theory. Possible factors that protect against the development of anorexia include high maternal body mass index (BMI) as well as high self-esteem.
How is anorexia nervosa diagnosed?
Anorexia nervosa can be a difficult disorder to diagnose, since individuals with anorexia often attempt to hide the disorder. Denial and secrecy frequently accompany other symptoms. It is unusual for a person with anorexia to seek professional help because the individual typically does not accept that she or he has a problem (denial). In many cases, the actual diagnosis is not made until medical complications have developed. The individual is often brought to the attention of a professional by family members only after marked weight loss has occurred. When anorexics finally come to the attention of a health-care professional, they often lack insight into their problem despite being severely malnourished and may be unreliable in terms of providing accurate information. Therefore, it is often necessary to obtain information from parents, a spouse, or other family members in order to evaluate the degree of weight loss and extent of the disorder. Health professionals will sometimes administer symptom questionnaires as part of screening for the disorder.
Warning signs of developing anorexia or one of the other eating disorders include excessive interest in dieting or thinness. One example of such interest includes a movement called "thinspiration," which promotes extreme thinness as a lifestyle choice rather than as a symptom of illness. There are a variety of web sites that attempt to inspire others toward extreme thinness by featuring information on achieving that goal, photos of famous, extremely thin celebrities, and testimonials, as well as before and after pictures of individuals who ascribe to extreme thinness.
The actual criteria for anorexia nervosa are found in
the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fifth
There are three basic criteria for the diagnosis of anorexia
nervosa that are characteristic:
- Restriction of food intake that leads to markedly low body weight for age,
gender, developmental course and medical health
- An intense fear of gaining weight or becoming fat, or persistent behavior
that prevents weight gain, despite the person being significantly underweight
- Self-perception that is grossly distorted, excessive emphasis on body weight
and shape in self-assessment, and weight loss or the seriousness thereof that is
either minimized or not acknowledged completely
The DSM-V further identifies two subtypes of anorexia nervosa. In the binge-eating/purging type, the individual regularly engaged in binge eating or purging behavior in at least the past three months, which involves self-induced vomiting or the misuse of laxatives, diuretics, or enemas during the current episode of anorexia. In the restricting type, the individual has severely restricted food intake and/or excessively exercised for at least the past three months but does not regularly engage in the behaviors seen in the binge-eating type.
In order to diagnose anorexia, the health-care professional distinguishes this illness from being a symptom of an underlying medical disorder or of another eating disorder. As a symptom of a medical disorder, the term anorexia (in general, rather than anorexia nervosa, the condition discussed in this article) describes the considerable weight loss that may be the result of serious illness that may afflict terminally ill patients who are receiving hospice care.
Unlike the binge-eating/purging type of anorexia nervosa, bulimia nervosa does not result in weight reduction below the minimal normal weight. Bulimia nervosa is characterized by episodes of eating significantly excessive amounts of food that the individual feels they cannot stop themselves from engaging in (binges), alternating with episodes of attempts to counteract the binges using inappropriate behaviors (purging) like self-induced vomiting, misuse of medications, fasting, and/or excessive exercising. Most individuals with an eating disorder do not fit neatly into either the diagnosis of anorexia or bulimia and are therefore classified as either suffering from "other
specified feeding or eating disorder" or "unspecified feeding or eating disorder." Examples of
other specified feeding or eating disorders include people with binge-eating disorder who experience episodes of binge eating but do not regularly engage in purging or restricting behaviors; individuals with recurrent purging behaviors without binge eating and recurrent episodes of night eating that is not better explained by binge eating disorder or another mental-health disorder. Those eating disorders that do not meet diagnostic criteria for any specific eating disorder are classified as an "unspecified feeding or eating disorder."
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What are anorexia symptoms and signs (psychological and behavioral)?
Anorexia can have dangerous psychological and behavioral effects on all aspects of an
individual's life and can affect other family members as well.
- The individual can become seriously
underweight, which can lead to or worsen depression and social withdrawal.
- The individual can
become irritable and easily upset and have difficulty interacting with others.
- Sleep can become
disrupted and lead to fatigue during the day.
- Attention and concentration can decrease.
- Most individuals with anorexia become obsessed with food
and thoughts of food. They think about it constantly and become compulsive about
their food choices or eating rituals. They may collect recipes, cut their food into tiny pieces,
prepare elaborate calorie-laden meals for other people, or hoard food.
Additionally, they may exhibit other obsessions and/or compulsions related to
food, weight, or body shape that meet the diagnostic criteria for an
obsessive compulsive disorder.
- Other psychiatric problems are also common in people with anorexia nervosa, including affective (mood) disorders, anxiety disorders, and personality disorders.
- Generally, individuals with anorexia are compliant in every other aspect of their life except for their relationship with food. Sometimes, they are overly compliant, to the extent that they lack adequate self-perception. They are
often eager to please and strive for perfection. They usually do well in school and may often overextend themselves in a variety of activities. The families of anorexics often appear to be "perfect." Physical appearances are important to the
anorexia sufferer. Performance in other areas is stressed as well, and they are often high achievers
in many areas.
- While control and perfection are critical issues for
individuals with anorexia, aspects of their life other than their eating habits are often
found to be out of control as well. Many have, or have had at some point in
their lives, addictions to alcohol, drugs, or gambling. Compulsions involving
sex, exercising, housework, and shopping are not uncommon. In particular, people
with anorexia often exercise compulsively to speed the
- Symptoms of anorexia in men tend to co-occur with other psychological problems and more commonly follow a period of being overweight than in women. Men with anorexia also tend to be more likely to have a distorted body image.
- Compared to symptoms in men, symptoms of anorexia in women tend to more frequently include a general displeasure with their body and a possibly stronger desire to be thin. Women with anorexia also tend to experience more perfectionism and cooperativeness.
In addition to the mental effects of anorexia, physical effects of this disorder in children and teens include a number of issues that are associated with growth and development inherent in this age group. Examples of symptoms and signs of anorexia in childhood and adolescence can include a slowing of the natural increase in height or a slowed development of other body functions like menses.
All of these features can negatively affect one's daily activities. Diminished interest in previously preferred activities can result or worsen. Some individuals also have symptoms that meet the diagnostic criteria for a major depressive disorder.
What is the treatment for anorexia nervosa?
Anorexia may be treated in an outpatient setting, or hospitalization may be necessary. For an individual with severe weight loss that has impaired organ function, hospital treatment must initially focus on correction of malnutrition, and intravenous feeding or tube feeding that goes past the mouth may be required. A gain of between 1 to 3 pounds per week is a safe and attainable goal when malnutrition must be corrected. Sometimes weight gain is achieved using schedules for eating, decreased physical activity, and increased social activity, either on an inpatient or outpatient basis. For individuals who have suffered from anorexia for several years, the goals of treatment may need to be achieved more slowly in order to prevent the anorexia sufferer from relapsing as a result of being overwhelmed by treatment.
The overall treatment of anorexia, however, must focus on more than weight gain. There are a variety of treatment approaches dependent upon the resources available to the individual. Many patients find that a short hospitalization followed by participation in a day treatment program is an effective alternative to longer inpatient programs. Most individuals, however, initially seek outpatient treatment involving psychological as well as medical intervention. It is common to engage a multidisciplinary treatment team consisting of a medical-care professional, a dietician or nutritionist, and a mental-health-care professional.
Different kinds of psychological therapy are employed to treat people with anorexia. Individual therapy, cognitive behavior therapy, group therapy, and family therapy have all been successful in the treatment of anorexia. In adolescents, research shows that the Maudsley model of family therapy can be particularly effective in treating this disorder in this population. In contrast to many past approaches to treatment, the Maudsley model approaches the family of the individual with anorexia as part of the solution rather than part of the reason their loved one has the disorder. With ongoing specific guidance from the professional mental-health team, this approach has the family actively help their loved one eat in a healthier manner.
Any appropriate treatment approach addresses underlying issues of control, perfectionism, and self-perception. Family dynamics are explored. Nutritional education provides a healthy alternative to weight management for the patient. Group counseling or support groups may assist the individual in the recovery process. The ultimate goal of treatment should be for the individual to accept herself/himself and lead a physically and emotionally healthy life.
While no medications have been identified that can definitively reduce the compulsion to starve oneself, olanzapine (Zyprexa, Zydis), risperidone (Risperdal), and quetiapine (Seroquel) are medications that are also used as mood stabilizers and to treat schizophrenia that may be useful in treating anorexia. These medications may also help increase weight and to manage some of the emotional symptoms like anxiety and depression that can accompany anorexia. Some of the selective serotonin reuptake inhibitor (SSRI) antidepressant drugs, like fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), citalopram (Celexa), and escitalopram (Lexapro), have been shown to be helpful in weight maintenance after weight has been gained, as well as having beneficial effects on the mood and anxiety symptoms that may be associated with the condition.
What is the prognosis (outcome) of anorexia
Anorexia is among the psychiatric conditions that have the highest mortality rate, with an estimated mortality (death) rate of up to 6% due to the numerous complications of the disease. The most common causes of death in people with anorexia are medical complications of the condition, including cardiac arrest and electrolyte imbalances. Suicide is also a cause of death in people with anorexia. In the absence of any coexisting
personality disorder, younger individuals with anorexia tend to do better over
time than their older counterparts.
Early diagnosis and treatment can improve the overall prognosis in an individual with anorexia. Despite most psychiatric medications having little effect on the symptoms that are specific to anorexia, the improvement in associated symptoms (for example, anxiety and depression) can help anorexia sufferers engage more actively in treatment and otherwise have a powerful, positive effect on the improvement that individuals with anorexia show over time. With appropriate treatment, about half of those affected will make a full recovery. Some people experience a fluctuating pattern of periods of weight gain followed by relapses, while others experience a progressively deteriorating course of the illness over many years, and still others never fully recover. It is estimated that about 20% of people with anorexia remain chronically ill from the condition.
As with many other mental-health illnesses with addictive symptoms, it takes a day-to-day effort to control the urge to relapse. Many individuals will require ongoing treatment for anorexia over several years, and some may require treatment over their entire lifetime. Factors that seem to predict more difficult recovery from anorexia include vomiting and other purging behaviors, bulimia nervosa, and symptoms of obsessive
personality disorder. The longer the disease goes on, the more difficult it is
to treat as well.
How can anorexia nervosa be prevented?
While educating the public about the important health benefits of appropriate nutrition is generally beneficial, it has been found to be less specifically helpful in the prevention of eating disorders and other body image problems. More effective approaches are thought to be the addition of education about the bias of media images toward excessive thinness as desirable. Helping people internalize a self-image
and health behaviors that are inconsistent with those of eating disordered
individuals have also found to be effective prevention methods for anorexia.
The future of anorexia nervosa
Given the complexity of anorexia and how many people with this illness continue to suffer from it despite receiving treatment, researchers are seeking to better understand how this illness develops and how it is most effectively treated.
For example, as individuals with anorexia tend to have low levels of cortisol in
their blood, and behaviors like dieting and exercise tend to increase cortisol
levels, giving anorexia sufferers cortisol supplements is being explored with some success. The best approaches for psychotherapy in adults with anorexia, the possible benefit of 12-step programs in treatment, the role of genetics in the development of this disorder, and the effectiveness of various medications in treating anorexia are other areas of continued need for research.
Where can a person get help for anorexia nervosa?
Academy for Eating Disorders
American Psychiatric Association
1000 Wilson Blvd, Suite 1825
Arlington, VA 22209
American Psychological Association
750 First Street, N.E.
Washington, D.C. 20002
National Eating Disorders Association
603 Stewart Street, Suite 803
Seattle, WA 98101
National Institute of Mental Health, NIH, HHS
National Institute of Health
9000 Rockville Pike
Bethesda, MD 20892
National Association of Anorexia Nervosa and Associated Disorders
T.H.E. (Treatment, Healing, Education) Center for Disordered Eating
297 Haywood Street
Asheville, NC 28801
Medically reviewed by Ashraf Ali, MD; Board Certification in Psychiatry and Adolescent & Child Psychiatry
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