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Day # 143: Intro to Eating Disorders

If you are following along in the suggested curriculum you have now finished the first ten themes (psychotic disorders, depressive disorders, bipolar disorder, anxiety disorders, emergency psychiatry, OCD and related disorders, trauma/stressor related disorders, dissociative disorders, psychosomatic disorders, and personality disorders). Nice work!

We will now begin the eleventh theme in the Bullet Psych curriculum which is eating disorders. Today we will provide a brief overview of these disorders and in the coming posts we will cover each disorder in detail.

Today's Content Level: Beginner

What Is An Eating Disorder? 1

•Eating disorders are characterized by a disturbance of body image and eating-related behaviors. These behaviors may damage functioning or physical health.

•Examples of eating disorders include anorexia nervosa, bulimia nervosa, binge-eating disorder, and more. There are many similarities between different types of eating disorders and patients often have features/behaviors of more than one. This can complicate diagnosis and treatment.

Examples of eating-related behaviors include drastic measures to avoid gaining weight such as significant reductions in caloric intake, fasting, excessive exercise, self-induced vomiting, and inappropriate use of laxatives, diuretics, or enemas. It may also include consuming excessive calories (binge eating) in response to negative emotions.

•An eating disorder is about more than just food. It is an illness characterized by unhealthy and consuming thoughts and behaviors regarding food, weight, and body image. It may affect all areas of life and make it difficult to work, go to school, or enjoy time with family, friends, or partners.

General Assessment 2, 3

•If you suspect an eating disorder ask a number of questions in order to estimate risk. What is your ideal body weight? What is the most/least you have weighed? Do you count calories/fat/carbs/protein? How much do you exercise? Do you have any fears regarding food or your weight? Have you eaten an unusually large amount of food and have had a sense of loss of control at the time? Have you ever made yourself sick (vomit) or taken laxatives as a way to control your weight? Do you have any food rituals? Consider screening with a more thorough validated questionnaire such as the Eating Disorder Examination Questionnaire (EDE-Q).

•Eating disorders can lead to a number of serious health risks including increased mortality or serious physical morbidity. We will cover these risks in more detail in following posts. For now, know that patients may experience electrolyte abnormalities, hypotension, amenorrhea, muscle wasting, cardiovascular complications, osteoporosis, heartburn, dehydration, kidney failure, and more.

Other psychiatric conditions often co-exist with eating disorders, particularly anxiety, depression, obsessive compulsive disorder, body dysmorphic disorder, post-traumatic stress disorder, personality disorders (OCPD, avoidant, borderline), and substance use disorders.

Epidemiology / Pathogenesis 4

•We will discuss the epidemiology and pathogenesis of each eating disorder in following posts, but here we will provide an overview.


  • Caused by a combination of genetic, biological, environmental, and psychosocial factors.

  • Risk factors include family history of eating disorders, age (teenage years = higher risk), gender (females at higher risk), poor body image, low self-esteem, perfectionistic traits, social pressure to be thin, neglect/abuse/trauma, type 1 diabetes, and being involved in a sport or activity with an emphasis on weight or size or involve subjective judging and weight classes. Examples of these activities include gymnastics, ballet, modeling, running, cheerleading, figure skating, wrestling, etc.


  • Prevalence: Lifetime prevalence is ~1% for anorexia nervosa, ~2% for bulimia nervosa, and ~4% for binge-eating disorder.

  • Gender: overall occurs in women more than men (3-10 times higher).

  • Age: can present at any age and varies somewhat by diagnosis. Most commonly presents in adolescence or early adulthood.

  • Please see disorder-specific posts for details of epidemiology and pathogenesis.

Overview of Eating and Feeding Disorders 5

We will now provide a brief overview of the eating and feeding disorders in the DSM-5. During subsequent posts we will cover each of these disorders in depth to include their full diagnostic criteria, epidemiology, work-up, differential diagnosis, and treatment.

Anorexia Nervosa

  • Restriction of energy intake relative to requirements.

  • Significantly low body weight (less than minimally normal in the context of age, sex, developmental trajectory, and physical health).

  • Intense fear of gaining weight / becoming fat OR persistent behaviors that prevent weight gain.

  • Disturbed body image OR undue influence of body weight/shape on self-evaluation OR lack of recognition of the seriousness of current low body weight.

  • Two main sub-types-> 1) Restricting type: Weight loss is achieved through restricting calories, fasting, and/or excessive exercise. Has not regularly engaged in binge-eating or purging behavior. 2) Binge-eating/purging type: Engages in eating binges followed by self-induced vomiting, and/or using laxatives, enemas, or diuretics. Some individuals purge after eating small amounts of food without binging.

  • Severity is specified based on BMI for adults and BMI percentile for children and adolescents. Mild = BMI ≥17. Moderate = BMI 16-16.99. Severe = BMI 15-15.99. Extreme = BMI <15. The level of severity may be increased to reflect clinical symptoms, degree of functional disability, or the need for supervision.

Bulimia Nervosa

  • Recurrent episodes of binge eating.

  • Recurrent inappropriate attempts to compensate for overeating and prevent weight gain. Examples include laxative abuse, vomiting, diuretics, fasting, or excessive exercise.

  • Binge eating and compensatory behaviors occur at least once a week for three months.

  • Sense of self-worth is excessively influenced by body weight and shape.

  • Does not occur exclusively during episodes of anorexia nervosa.

  • Severity is based on the frequency of inappropriate compensatory behaviors per week. Mild = 1-3. Moderate = 4-7. Severe = 8-13. Extreme = ≥14. The level of severity may be increased to reflect other symptoms and the degree of functional disability.

  • Keep in mind that individuals with bulimia nervosa typically are within the normal weight or overweight range (BMI > 18.5 and < 30 in adults).

Binge-Eating Disorder

  • Recurrent episodes of binge eating.

  • Binge eating episodes are associated with ≥3 of the following: eating very rapidly, eating until uncomfortably full, eating large amounts when not hungry, eating alone due to embarrassment, and feeling disgusted/depressed/guilty after eating.

  • Marked distress regarding binge eating.

  • Binge eating occurs at least once a week for three months.

  • Not associated with compensatory behaviors (such as vomiting, laxative use, excessive exercise, etc.).

  • Does not occur exclusively during the course of anorexia or bulimia.

  • Severity is based on the frequency of binge eating episodes per week. Mild = 1-3. Moderate = 4-7. Severe = 8-13. Extreme = ≥14. The level of severity may be increased to reflect other symptoms and the degree of functional disability.

Avoidant/Restrictive Food Intake Disorder

  • Eating or feeding disturbance that leads to a persistent failure to meet appropriate nutritional needs.

  • Eating disturbance is not caused by distorted body image, but is rather caused by either an apparent lack of interest in food or avoidance based on sensory characteristics of food or consequences of eating. More on this in a later lesson.

Rumination Disorder

  • Recurrent regurgitation of food for at least one month.

  • Regurgitated food may be re-chewed, re-swallowed, or spit out.

  • Not attributable to another medical condition (gastroesophageal reflex, pyloric stenosis, etc.) or psychiatric condition (anorexia, bulimia, etc.).


  • Persistent eating of nonnutritious nonfood substances for at least one month.

  • The eating of these substances is inappropriate to the developmental level of the individual and their cultural or social norms.

  • Typical substances vary but may include paper, cloth, hair, soap, string, soil, chalk, paint, gum, metal, pebbles, charcoal, ice, etc.


This post should be a review for intermediate learners, but hopefully this provided a helpful overview for beginners. Next post we will discuss anorexia nervosa in more detail.

Resources used today include:

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