Eating Disorders Overview
Complications of Bulimia Nervosa
People with bulimia nervosa may make themselves vomit or use laxatives or diuretics to rid themselves of consumed calories. Many medical problems are directly associated with purging behavior, including:
Complications of Anorexia Nervosa
Anorexia nervosa can increase the risk for serious health problems such as:
Treatment of Bulimia Nervosa
Treatment of Anorexia Nervosa
Eating disorders are psychological problems marked by an obsession with food and weight. The main types of eating disorders are:
There are three main features of anorexia nervosa:
Anorexia nervosa has two subtypes, based on a patient’s behavior during the past 3 months:
Bulimia nervosa is characterized by cycles of bingeing and purging:
Bingeing without purging is characterized as uncontrolled overeating (binge eating) with the absence of purging behaviors, such as vomiting or laxative abuse (used to eliminate calories). Binge eating usually leads to becoming overweight.
Binge eating is characterized by:
There is no single cause for eating disorders. Although concerns about weight and body shape play a role in all eating disorders, the actual cause of these disorders appears to involve many factors, including those that are genetic and neurobiological, cultural and social, and behavioral and psychological.
Anorexia is much more common in people who have relatives with the disorder. Studies of twins show they have a tendency to share specific eating disorders (anorexia nervosa, bulimia nervosa, and obesity). Researchers have identified specific chromosomes that may be associated with bulimia and anorexia.
The body’s hypothalamic-pituitary-adrenal axis (HPA) may be important in eating disorders. This complex system originates in the following regions in the brain:
The HPA system releases certain neurotransmitters (chemical messengers in the brain) that regulate stress, mood, and appetite. Three neurotransmitters -- serotonin, norepinephrine, and dopamine -- may play a particularly important role in eating disorders.
Serotonin is involved with well-being, anxiety, and appetite (among other traits). Norepinephrine is a stress hormone. Dopamine is involved in reward-seeking behavior. Imbalances with serotonin and dopamine may explain in part why people with anorexia do not experience a sense of pleasure from food and other typical comforts.
Many patients with eating disorders also experience depression, anxiety disorders, and obsessive-compulsive disorder (OCD). It is not clear if these disorders, particularly OCD, cause the eating disorders, increase susceptibility to them, or share common biologic causes.
Obsessive-Compulsive Disorder (OCD). Obsessive-compulsive disorder is a mental health disorder that may occur in up to two thirds of patients with anorexia and up to a third of patients with bulimia. Some doctors believe that eating disorders are variants of OCD.
Obsessions are recurrent or persistent mental images, thoughts, or ideas, which may result in compulsive behaviors, which are repetitive, rigid, and self-prescribed routines. Women with anorexia and OCD may become obsessed with exercise, dieting, and food. They often develop compulsive rituals (weighing every bit of food, cutting it into tiny pieces, or putting it into small containers.
Body Dysmorphic Disorder. Body dysmorphic disorder (BDD) is related to OCD. It is a compulsive disorder that involves a distorted obsession with finding fault with one's body. BDD is often associated with anorexia or bulimia, but it can also occur without any eating disorder.
Muscle dysmorphia is a form of body dysmorphic disorder in which the obsession involves musculature and muscle mass. It tends to occur in men who perceive themselves as being underdeveloped or "puny," which results in excessive body building, preoccupation with diet, use of anabolic steroids, and eating disorders.
Cultural values that emphasize only certain types of body shapes as desirable or normal contribute to eating disorders. The media plays a role in promoting these unrealistic expectations for body image and a distorted cultural drive for thinness. At the same time, cheap and high-caloric foods are aggressively marketed. Such messages are contradictory and confusing.
Anorexia nervosa and bulimia nervosa occur most often in adolescents and young adults. These disorders rarely begin before puberty or after age 40. Binge eating disorder typically begins during adolescence or young adulthood, but it can also first develop in older adults.
Eating disorders occur predominantly among girls and women. About 90 - 95% of patients with anorexia nervosa, and about 80% of patients with bulimia nervosa, are female.
Most studies of individuals with eating disorders have focused on Caucasian middle-class females. However, eating disorders can affect people of all races and socioeconomic levels.
Some people with eating disorders are survivors of emotional or physical trauma. These stressful life experiences may have included physical or sexual abuse, painful loss of loved ones, or having lived through war or natural disasters. Bullying may contribute to eating disorders, especially if the ridicule and humiliation are directed at the victim’s weight and body shape.
Research indicates that exposure to trauma, and development of post-traumatic stress disorder (PTSD), may increase the risk for eating disorders.
People with eating disorders tend to share certain personality and behavioral traits including low self-esteem and obsessions with weight and body shape and size. There are also differences depending on the type of eating disorder:
A history of dieting or food restriction is associated with increased risk for eating disorders. Although there is no evidence that families or parents cause eating disorders, research suggests that parental conversations that focus on weight and size may increase the risk for eating disorders. In contrast, engaging adolescents in conversations about healthy eating may help prevent eating disorders.
Excessive exercise is associated with many cases of anorexia (and, to a lesser degree, bulimia). In young female athletes, exercise and low body weight postpone puberty, allowing girls to retain a muscular boyish shape without the normal accumulation of fatty tissues in breasts and hips that may blunt their competitive edge. Coaches and teachers may compound the problem by overemphasizing calorie counting and loss of body fat.
The "female athlete triad" syndrome is a combination of eating disorders, amenorrhea (absent or irregular menstruation), and osteoporosis (loss of bone mineral density). However, eating disorders also affect male athletes. Male wrestlers are particularly notorious for using a method called weight-cutting for rapid weight loss. This process involves food restriction and fluid depletion by using steam rooms, saunas, laxatives, and diuretics.
Eating disorders are very serious illnesses that have wide range of effects on the body and mind. They are frequently associated with a number of other medical problems, ranging from frequent infections and general poor health to life-threatening conditions.
Purging can cause extensive damage throughout the digestive tract. Complications include:
Heart disorders are the most common medical causes of death in people with severe anorexia nervosa. The effects of anorexia on the heart include:
Starvation, binge eating, and purging can cause damage to many of the body’s organs including the kidneys, lungs, and liver. Severe anorexia nervosa can cause multi-organ failure.
Starvation can cause serious hormonal changes, which may have severe health consequences. Hormones affected include:
The result of many of these hormonal abnormalities in women is long-term, irregular or absent menstruation (amenorrhea). This can occur early on in anorexia, even before severe weight loss. Over time this causes infertility and pregnancy complications, bone density loss (osteoporosis), and other problems.
In children and adolescents with eating disorders, hormonal abnormalities can interfere with normal bone development and growth.
Nearly all women with anorexia experience osteopenia (loss of bone calcium), and many have osteoporosis (more advanced loss of bone density). Up to two-thirds of children and adolescent girls with anorexia fail to develop strong bones during their critical growing period. Boys with anorexia also suffer from stunted growth. The less the patient weighs, the more severe the bone density loss. Patients who binge-purge face an even higher risk for bone density loss.
Bone density loss in women is mainly due to low estrogen levels that occur with anorexia. Other biologic factors in anorexia also may contribute to bone density loss, including high levels of stress hormones (which impair bone growth) and low levels of calcium, certain growth factors, and DHEA (a weak male hormone). Weight gain, unfortunately, does not completely restore bone. Only achieving regular menstruation as soon as possible can protect against permanent bone density loss. The longer the eating disorder persists the more likely the bone density loss will be permanent.
Testosterone levels decline in boys as they lose weight, which also can affect their bone density. In boys with anorexia, weight restoration produces some catch-up growth, but it may not produce full growth.
Anemia (reduced number of red blood cells) is a common result of malnutrition and starvation. A particularly serious blood problem is caused by severely low levels of vitamin B12. If anorexia becomes extreme, the bone marrow dramatically reduces its production of blood cells, a life-threatening condition called pancytopenia.
Tooth erosion, cavities, mouth sores, and gum problems are common in people who purge. The stomach acid caused by forced vomiting erodes tooth enamel and dries out the saliva glands.
Dehydration affects people with bulimia nervosa and anorexia nervosa. It can cause dry, flaky skin and brittle hair. Patients may lose hair on the scalp, but grow a layer of downy hair elsewhere, which is the body’s attempt to try to stay warm.
Neurological conditions associated with severe anorexia nervosa include:
Imaging scans indicate that parts of the brain physically shrink (atrophy) during anorexic states. Weight gain helps many patients recover brain function, but some damage may be permanent.
Anxiety disorders and depression are common in people with eating disorders. Patients are also at higher risk for substance abuse including smoking (to help prevent weight gain), alcohol, and drug abuse. In addition to illicit drugs, people with eating disorders often abuse over-the-counter laxatives, diuretics, appetite suppressants, and drugs that induce vomiting (such as ipecac). Some patients with anorexia nervosa are at risk for suicidal behavior. .
Eating disorders are particularly serious for people with either type 1 or type 2 diabetes.
Low blood sugar (hypoglycemia) is a danger for anyone with anorexia, but it is a particularly dangerous risk for patients with diabetes, especially those who take supplemental insulin. If patients do not take their insulin, dangerous high blood sugar (hyperglycemia) can occur. Unfortunately, patients with eating disorders may skip or reduce their daily insulin in order to decrease their body’s utilization of calories.
Extremely high blood sugar levels can cause life-threatening complications. They include diabetic ketoacidosis, a condition in which acidic chemicals (ketones) accumulate in the body. This condition can lead to coma and death.
The main symptom of anorexia nervosa is major weight loss from excessive and continuous dieting.
Behavioral symptoms and warning signs of anorexia may include:
Other symptoms of anorexia may include:
Symptoms and signs of binge eating and purging behaviors may include:
The first step toward a diagnosis is to admit the existence of an eating disorder. Often, the patient needs to be compelled by a parent or others to see a doctor because the patient denies and resists the problem. Some patients may even self-diagnose their condition as an allergy to carbohydrates, because after being on a restricted diet, eating carbohydrates can produce gastrointestinal problems, dizziness, weakness, and palpitations. This may lead such people to restrict carbohydrates even more severely.
According to the American Psychiatric Association, patients with eating disorders (especially anorexia nervosa) frequently lack insight into their condition. Therefore, doctors may turn to family members and other sources for information regarding weight loss and additional symptoms. Because people who purge tend to have complications with their teeth and gums, dentists can play a role in identifying eating disorders.
A doctor will evaluate a patient’s body mass index (BMI). The BMI is a measurement of body fat. It is derived by multiplying a person's weight in pounds by 703 and then dividing it twice by the height in inches. (BMI calculators are available online.)
For example, a woman who is 5'5" and weighs 125 pounds has a healthy BMI of 21. A woman at the same height who weighs 90 pounds would have a dangerously low BMI of 15.
A doctor will carefully evaluate a patient’s weight and other physical and emotional symptoms. Eating disorders are diagnosed based on criteria from the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM). [See Introduction section of this report for a complete list of diagnostic criteria.] The criteria outline specific behaviors and symptoms that define anorexia nervosa, bulimia nervosa, binge-eating disorder, and other eating disorders. .
Once a diagnosis is made, a doctor will check for any serious complications of eating disorders. Tests may include:
Various questionnaires are available for assessing patients. The Eating Disorders Examination (EDE), which is an interview of the patient by the doctor, and the self-reported Eating Disorders Examination-Questionnaire (EDE-Q) are both considered valid tests for diagnosing eating disorders and determining specific features of the condition (such as vomiting or laxative use).
Another test is called the SCOFF questionnaire. Answering yes to two of these questions is a strong indicator of an eating disorder:
Do you make yourself Sick because you feel uncomfortably full?
Do you worry you have lost Control over how much you eat?
Have you recently lost more than One stone's worth of weight (14 pounds) in a 3-month period?
Do you believe yourself to be Fat when others say you are too thin?
Would you say that Food dominates your life?
Treatment goals for eating disorders include:
A multidisciplinary team approach with consistent support and counseling is essential for long-term recovery. Depending on the severity and type of eating disorder, team members may include:
All healthcare providers should be experienced in treating eating disorders.
Eating disorders are nearly always treated with some form of psychological treatment, often tied in with nutritional counseling. Depending on the disorder and the individual patient, certain psychotherapeutic approaches may work better than others.
Nutritional rehabilitation counseling is essential for recovery. It can help patients develop structured meal plans and healthy eating and weight management. In anorexia nervosa, family-based therapies that involve the parent’s assistance in feeding their adolescent child have proven to be very helpful.
Medications such as selective serotonin reuptake inhibitor (SSRI) antidepressants may be added to psychotherapy for bulimia, but there is limited evidence that these or other drugs have any significant effect on anorexia nervosa.
Although anorexia nervosa generally presents more treatment challenges than bulimia nervosa, long-term studies show recovery in many people treated for anorexia. Studies indicate that a majority of people with bulimia nervosa, and up to half of patients with anorexia nervosa, are free from eating disorders within 10 years of treatment.
The patient’s overall physical condition, psychology, behavior, social circumstances, and health insurance determine the type of treatment facility -- inpatient hospitalization, residential hospitalization, partial hospitalization, or outpatient care. Patients and their families should discuss with their doctors the various options available and how structured and intense the treatment should be.
Moderately to severely ill anorexic patients may require hospitalization when:
When severe metabolic or medical problems occur, patients with anorexia may need to be hospitalized either voluntarily or involuntarily. A variety of partial hospitalization or day care programs are also available.
For people with severe anorexia, many doctors recommend 10 - 12 weeks of hospitalization with full nutritional support in order for the patient to reach ideal body weight. It is particularly important for women with both diabetes and anorexia to achieve 100% of ideal weight before being released from an inpatient facility.
Nutrition rehabilitation and psychotherapy are the cornerstones of anorexia nervosa treatment. Patients may also require treatment of medical problems related to the condition, such as bone loss, and imbalances in important electrolytes.
Nutritional intervention is essential. Weight gain is associated with fewer symptoms of anorexia and with improvements in both physical and mental function. Restoring good nutrition can help reduce bone density loss. Raising the level of energy available to the body by balancing food intake and exercise can normalize hormonal function. Restoring weight is also essential before the patient can fully benefit from additional psychotherapeutic treatments.
Goals for Weight Gain and Good Nutrition. A weight-gain goal of 2 - 3 pounds a week for hospitalized patients, and 0.5 - 1 pound a week for outpatients, is strongly encouraged. Patients typically begin with a calorie count as low as 1,000 - 1,600 calories a day, which is then gradually increased to 2,000 - 3,500 calories a day. Patients may initially experience intensified anxiety and depressive symptoms, as well as fluid retention, in response to weight gain. These symptoms decrease as the weight is maintained.
Tubal Feedings. Feeding tubes that pass through the nose to the stomach are not commonly used, since they may discourage a return to normal eating habits and because many patients interpret their use as punishing forced feeding. However, for patients who are at significant risk or for those who refuse to eat, tube feeding through the nose or through a tube inserted through the abdomen into the stomach can help with weight gain and improve the nutritional status of the patient.
Intravenous Feedings. Intravenous feedings may be needed in life-threatening situations. This involves inserting a needle into the vein and infusing fluids containing nutrients directly into the bloodstream. Intravenous feedings must be administered carefully. When given at home, no more than the prescribed amount should be used. Excessive amounts of glucose solutions can cause phosphate levels to drop severely and trigger a condition called hypophosphatemia. Emergency symptoms include irritability, muscle weakness, bleeding from the mouth, disturbed heart rhythms, seizures, and coma.
The Maudsley Approach. For adolescent and other younger patients in the early stages of anorexia nervosa, the Maudsley approach to “refeeding” may be effective. The Maudsley approach is a type of family therapy that enlists the family as a central player in the patient’s nutritional recovery. Parents take charge of planning and supervising all of the patient’s meals and snacks. As recovery progresses, the patient gradually takes on more personal responsibility for determining when and how much to eat. Weekly family meetings and family-based counseling are also part of this therapeutic approach.
Psychotherapy. Psychotherapy is the main therapeutic approach for anorexia nervosa. Psychotherapy may be given in an individual, group, or family setting. Family therapy is an important component of anorexia treatment for children and adolescents.
Individuals usually begin with a form of psychodynamic psychotherapy that provides an empathetic setting, addresses unresolved emotional issues, and rewards positive efforts towards weight gain. After weight is restored, cognitive behavioral therapy techniques may be helpful.
Antidepressants. Studies have not reported benefits for treating anorexia nervosa with selective serotonin reuptake inhibitors (SSRIs), the antidepressants that are often useful for patients with bulimia. A few studies suggest that these drugs could be useful for people with anorexia nervosa who also have obsessive-compulsive disorder (OCD).
Nutritional Supplements. Iron supplements may be needed for anemia treatment, and calcium and vitamin D supplements may be recommended for osteoporosis prevention. Some studies have reported that zinc supplements may help patients gain weight.
The role of exercise in recovery is complex, since for those with anorexia excessive exercise is often a component of the original disorder. However, very controlled exercise regimens may be used as both a reward for developing good eating habits and as a way to reduce the stomach and intestinal distress that accompanies recovery. Exercise should not be performed if severe medical problems still exist and if the patient has not gained significant weight. The goal of exercise should be on improving physical fitness and health, not on burning off calories.
Some doctors recommend a stepped approach for patients with bulimia nervosa or binge-eating disorder, which follow specific stages depending on the severity and response to initial treatments:
Outpatient treatment is recommended for most patients with these eating disorders. Patients with bulimia nervosa rarely need hospitalization except under the following circumstances:
Psychotherapy. Cognitive-behavioral therapy (CBT) is the first-line of therapy for most patients with bulimia nervosa or binge-eating disorder. Interpersonal therapy may be tried if CBT fails. In interpersonal therapy (also known as "talk therapy"), therapists help patients explore how social and family relationships may affect their eating disorder.
Antidepressants. The most common antidepressants prescribed for bulimia nervosa or binge-eating disorder are selective serotonin reuptake inhibitors (SSRIs) such as:
Studies are mixed, however, on whether SSRIs offer an additional advantage in reducing binge-eating compared to CBT. Fluoxetine has been approved for bulimia and is considered the drug of choice, although some studies suggest that other SSRIs work just as well. Other types of antidepressants, such as tricyclics, MAO inhibitors, and bupropion (Wellbutrin, generic), carry more risks of side effects than SSRIs and do not appear to be effective for treatment of bulimia.
Antidepressants may increase the risks for suicidal thoughts and actions during the first few months of treatment. In particular, adolescents and young adults should be carefully monitored during this time period for any changes in behavior.
Topiramate. The antiepileptic drug topiramate (Topamax, generic) has been shown in studies to reduce bingeing and purging episodes in patients with bulimia nervosa and binge-eating disorder. However, this drug can cause serious side effects including birth defects. In addition, because people tend to lose weight while taking topiramate, it should not be used by patients who have low or even normal body weight.
Eating disorders are nearly always treated with some form of psychotherapy. Depending on the problem, different psychological approaches may work better than others.
Cognitive-behavioral therapy (CBT) works on the principle that a pattern of false thinking and belief about one's body can be recognized objectively and altered, thereby changing the response and eliminating the unhealthy reaction to food. One approach for bulimia nervosa is the following:
Interpersonal therapy deals with depression or anxiety that might underlie the eating disorders along with social factors that influence eating behavior. This therapy does not deal with weight, food, or body image at all.
The goals are to:
Motivational enhancement therapy is another form of behavioral therapy that uses an empathetic approach to help patients understand and change their behaviors concerning food. It may be offered in an individual or group setting.
Focal psychodynamic therapy (FPT) focuses on how unresolved early childhood experiences may play a role in the later development of eating disorders. The therapist helps the patient gain insight into how certain stresses and conflicts in a person’s early years may have created emotional patterns and negative ways of thinking that lie beneath the eating disorder. This therapy has been found to be helpful in treating patients with anorexia nervosa.
Dialectical behavioral therapy (DBT) incorporates mindfulness, acceptance skills, interpersonal skills, and emotional regulation. It focuses on the role of emotions and how people may use food as an inappropriate coping strategy for dealing with emotional distress. A DBT therapist will work with patients to help them find more effective ways to deal with emotional stressors. DBT appears to be an effective psychotherapy for patients with bulimia nervosa and binge eating disorder, and other mental health conditions associated with impulsiveness.
Because a patient’s eating disorder affects the entire family, family therapy can be an important component of recovery. It can help all family members better understand the complex nature of eating disorders, improve their communication skills with one another, and teach strategies for coping with stress and negative feelings. Family-based psychotherapies are also integral parts of nutritional rehabilitation counseling programs, such as the Maudsley approach.
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Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team. Editorial Update: 04/18/2014.