An Overview of Eating Disorders


Wilson Gutierrez, General Editor

Eating disorders are any illness characterized primarily by a pathological disturbance in people’s eating behaviors. Common eating disorders include anorexia nervosa, bulimia nervosa, and binge-eating disorder. Other eating disorders include pica and rumination, which are usually diagnosed in infancy or early childhood. Behaviors associated with eating disorders include restrictive eating or avoiding certain foods, binge eating, vomiting or laxative misuse or compulsive exercise. They can have a serious impact on physical, psychological, and social function in ways that appear like an addiction. 

5% of the population are affected by eating disorders and are seen most often in adolescence and adulthood. Although more common in teenage women, men and boys can also be vulnerable. People occasionally have eating disorders without their families or friends ever suspecting that they have a problem. Eating disorders often occur with other psychiatric disorders, most often mood and anxiety disorders, obsessive compulsive disorder and problems of alcohol and drug abuse. There is evidence that genes and heredity play a role in why some people have a higher risk of eating disorders, but these disorders can also affect those who have no family history of the condition. Treatment should deal with psychological, behavioral, nutritional, and other medical complications. Ambivalence towards treatment, denial of a problem with eating and weight, or concern about changing eating patterns is common. People with eating disorders can resume healthy eating habits and restore their emotional and psychological health if proper medical care is considered.

Anorexia Nervosa: 

Anorexia nervosa means loss of appetite and is characterized by self-starvation and weight loss resulting in low weight for height and age. Anorexia has the highest mortality of any psychiatric diagnosis other than opioid use disorder and can be an extremely serious condition. Body mass index or BMI, a measure of weight for height, is typically under 18.5 in an adult individual with anorexia nervosa. 

Dieting behavior in anorexia nervosa is driven by an intense fear of gaining weight or becoming fat. Although some individuals with anorexia will say they want to and are trying to gain weight, their behavior is not consistent with this resolution. Some individuals with anorexia nervosa also recurrently binge eat and or purge by vomiting or laxative misuse. 

There are two sub-types of anorexia nervosa: 

  • restricting type, in which individuals lose weight primarily by dieting, fasting or excessively exercising, and 
  • binge-eating/purging type in which persons also engage in intermittent binge eating and/or purging behaviors. 

Over time, some of the following symptoms may develop related to starvation or purging behaviors. Serious medical complications can be life threatening and include heart rhythm abnormalities especially in those patients who vomit or use laxatives, kidney problems or seizures. 

  • Menstrual periods cease 
  • Dizziness or fainting from dehydration 
  • Brittle hair/nails 
  • Cold intolerance 
  • muscle weakness and waste 
  • Heartburn and reflux 
  • Severe constipation, bloating and fullness after meals 
  • Stress fractures from compulsive exercise as well as bone loss resulting in osteopenia or osteoporosis (thinning of the bones) 
  • Depression, irritability, anxiety, poor concentration, and fatigue 

Treatment for anorexia nervosa involves helping those affected normalize their eating and weight control behaviors and restore their weight. Medical evaluation and treatment of any co-occurring psychiatric or medical conditions is a vital component of the treatment plan. The nutritional plan should focus on helping individuals counter anxiety about eating and practice consuming a wide and balanced range of foods of different calorie densities across regularly spaced meals. Addressing body dissatisfaction is also important.

In the case of severe anorexia nervosa when outpatient treatment is not effective, admission to an inpatient or residential behavioral specialty program may be indicated. Most specialty programs are effective in restoring weight and normalizing eating behavior, although the risk of relapse in the first year following program discharge remains significant.  

Bulimia Nervosa: 

Individuals with bulimia nervosa change between dieting or eating low calorie foods with binge eating on high calorie foods. Binge eating can be defined as eating large quantities of food within a brief period of time. Binge behavior is usually secretive and linked to feelings of shame or embarrassment. Binges can be large and food is often consumed rapidly to the point of nausea and discomfort.

Binges can occur weekly and are typically followed by what are called “compensatory behaviors” to prevent weight gain. These can include fasting, vomiting, laxative misuse, or compulsive exercise. As in anorexia nervosa, persons with bulimia nervosa are excessively preoccupied with thoughts of food, weight or shape which negatively affect, and disproportionately impact, their self-esteem. 

Individuals with bulimia nervosa can be slightly underweight, normal weight, overweight or even obese. If they are underweight however, they are considered to have anorexia nervosa binge-eating/purging type not bulimia nervosa. It may be difficult for family members or friends to identify whether a person has bulimia nervosa because they do not appear underweight and they hide their behaviors. Possible signs that someone may have bulimia nervosa include: 

  • Frequent trips to the bathroom right after meals 
  • Copious amounts of food disappearing or unexplained empty wrappers and food containers 
  • Chronic sore throat 
  • Swelling of the salivary glands in the cheeks 
  • Dental decay resulting from erosion of tooth enamel by stomach acid 
  • Heartburn and gastroesophageal reflux 
  • Laxative or diet pill misuse 
  • Recurrent unexplained diarrhea 
  • Misuse of diuretics (water pills) 
  • Feeling dizzy or fainting from excessive purging behaviors resulting in dehydration 

Bulimia can lead to rare but potentially fatal complications including esophageal tears, gastric rupture, and dangerous cardiac arrhythmias. In cases of severe bulimia nervosa, patients may be under constant medical monitoring in order to identify and treat any possible complications. Outpatient cognitive behavioral therapy for bulimia nervosa helps patients normalize their eating behavior and manage thoughts and feelings that perpetuate the disorder. Antidepressants can also be helpful in decreasing urges to binge and vomit. 


Binge Eating Disorder: 

People with binge eating disorder have bursts of binge eating in which they consume enormous quantities of food in a brief period, experience a sense of loss of control over their eating and are distressed by the binge behavior. Unlike people with bulimia nervosa however, they do not extensively use compensatory behaviors to get rid of the food by inducing vomiting, fasting, exercising or laxative misuse. Binge eating is chronic and can lead to serious health problems like obesity, diabetes, hypertension, and cardiovascular diseases. 

The diagnosis of binge eating disorder requires frequent binges, associated with a sense of lack of control and with three or more of the following features: 

  • Eating more rapidly than normal 
  • Eating until uncomfortably full 
  • Eating substantial amounts of food when not feeling hungry 
  • Eating alone because of feeling embarrassed by how much one is eating 
  • Feeling disgusted with oneself, depressed or very guilty afterward 

Cognitive behavioral psychotherapy for binge eating is the most helpful treatment. Interpersonal therapy has also been shown to be effective, as have several antidepressant medications. 

Other Specified Feeding and Eating Disorders:

Eating disorders or disturbances of eating behavior that cause distress and impair family, social or work function but do not fit the other categories are listed here. If the frequency of the behavior does not meet the diagnostic threshold or the weight criteria for the diagnosis of anorexia nervosa are not met.  An example of another specified feeding and eating disorder is “atypical anorexia nervosa”. This category includes individuals who may have lost a lot of weight and whose behaviors and degree of fear of fatness is consistent with anorexia nervosa, but who are not yet considered underweight based on their BMI because their baseline weight was above average.  Since the speed of weight loss is related to medical complications, individuals who lose a lot of weight rapidly by engaging in extreme weight control behaviors can be at elevated risk of medical complications, even if they appear normal or above average weight. 


Avoidant Restrictive Food Intake Disorder: 

Avoidant/restrictive food intake disorder (ARFID) is a newy defined eating disorder that involves a disruption in eating resulting in failure to meet nutritional needs and extreme picky eating. In AFRID, the following points are caused by food avoidance or limited food repertoire.

  • Low appetite and lack of interest in eating or food in general. 
  • Extreme food avoidance based on sensory characteristics of foods like texture and smell
  • Anxiety or concern about the consequences of eating, such as fear of vomiting, nausea, choking, constipation, an allergic reaction, and more. The disorder may be brought on in response to a significant negative event such as an episode of choking or food poisoning followed by the avoidance of an increasing variety of foods.

The diagnosis of ARFID is associated with one or more of the following: 

  • Significant weight loss (or failure to achieve expected weight gain in children). 
  • Significant nutritional deficiency. 
  • The need to rely on a feeding tube or oral nutritional supplements to maintain sufficient nutrition intake. 
  • Interference with social functioning (such as inability to eat with others). 

The impact on physical and psychological health and degree of malnutrition can be similar to that seen in people with anorexia nervosa. However, people with ARFID do not have excessive concerns about their body weight or shape and the disorder is distinct from anorexia nervosa or bulimia nervosa. Also, while individuals with autism spectrum disorder often have rigid eating behaviors and sensory sensitivities, these do not necessarily lead to the level of impairment required for a diagnosis of avoidant/restrictive food intake disorder. 

ARFID does not include food restriction related to lack of availability of food; normal dieting; cultural practices, such as religious fasting; or developmentally normal behaviors, such as toddlers who are fussy eaters. 

Food avoidance or restriction commonly develops in infancy or early childhood and may continue in adulthood. It can, however, start at any age. Regardless of the age of the person affected, ARFID can impact families, causing increased stress at mealtimes and in other social eating situations. 

Treatment for ARFID involves an individualized plan and may involve several specialists including a mental health professional, a registered dietitian nutritionist, and others. 



Pica is an eating disorder in which a person constantly eats things that are not typically eaten as food and has no nutritional value. The behavior can last for over a month and is severe enough to warrant clinical attention. Typical substances ingested might include paper, paint chips, soap, cloth, hair, string, chalk, metal, rocks, charcoal or coal, or clay. Individuals with pica do not typically have an aversion to food in general. 

Pica may first occur in childhood, adolescence, or adulthood. Putting small objects into their mouth is a normal part of development for children under 2 so it is not diagnosed at this age. Pica often occurs along with autism spectrum disorder and intellectual disability but can occur in otherwise typically developing children. A person diagnosed with pica is at high risk of intestinal blockages or toxic effects of substances consumed. Treatment involves testing for nutritional deficiencies and behavioral interventions including redirecting the individual from nonfood items and rewarding them for avoiding them.


Rumination Disorder: 

Rumination disorder involves repeated regurgitation of food that is re-chewed or re-swallowed. This means that swallowed food is brought back up into the mouth and is re-chewed and re-swallowed or spat out. Rumination disorder can occur in infancy, childhood, and adolescence or in adulthood. The habits to meet the diagnosis are listed below:

To meet the diagnosis the behavior must: 

  • Occurs repeatedly over at least a 1-month period 
  • Not due to a gastrointestinal or medical problem 
  • Not occur as part of one of the other behavioral eating disorders listed above 
  • Rumination can also occur in other mental disorders, however the degree must be severe enough to warrant separate clinical attention for the diagnosis to be made. 


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