The current psychiatric diagnostic manual (DSM-5-TR) recognizes seven feeding and eating disorders: anorexia nervosa, bulimia nervosa, binge eating disorder, avoidant/restrictive food intake disorder (ARFID), other specified feeding and eating disorder (OSFED), pica, and rumination disorder. That count of seven covers the formal categories, but OSFED alone contains five subcategories, so the real number of distinct presentations is closer to a dozen.
About 9% of the U.S. population, roughly 31 million people, will have an eating disorder in their lifetime. Globally, prevalence more than doubled between 2000 and 2018, rising from 3.5% to 7.8%. Here’s what each type looks like and how they differ from one another.
Anorexia Nervosa
Anorexia nervosa involves persistent restriction of food intake that leads to significantly low body weight, an intense fear of gaining weight, and a distorted sense of one’s own body size or shape. People with anorexia often don’t recognize how underweight they are, or they minimize the seriousness of their low weight.
The physical toll is severe. Prolonged starvation can cause thinning bones, muscle wasting, brittle hair and nails, dry or yellowish skin, and the growth of fine hair all over the body as the body tries to stay warm. Heart rate and blood pressure drop. Internal body temperature falls, leaving a person feeling cold constantly. In serious cases, anorexia causes heart damage, brain damage, organ failure, and infertility. It carries the highest mortality rate of any mental illness, with deaths resulting from both medical complications and suicide.
Bulimia Nervosa
Bulimia nervosa is defined by repeated episodes of eating large amounts of food in a short period (bingeing), followed by behaviors meant to prevent weight gain (purging). Purging usually means self-induced vomiting, but it can also involve laxative misuse, fasting, or excessive exercise. Unlike anorexia, people with bulimia often maintain a relatively normal weight, which can make the disorder harder to spot from the outside.
Repeated vomiting exposes the teeth and throat to stomach acid, leading to worn enamel, tooth decay, a chronically sore throat, and swollen salivary glands along the jaw. The more dangerous consequences are internal: severe dehydration and electrolyte imbalances that can trigger a stroke or heart attack. Acid reflux and other gastrointestinal problems are common as well.
Binge Eating Disorder
Binge eating disorder (BED) is the most common eating disorder in the United States. It shares the binge episodes of bulimia, where a person eats an unusually large amount of food and feels unable to stop, but there is no regular purging afterward. Episodes are typically accompanied by eating much faster than normal, eating until uncomfortably full, eating large amounts when not hungry, eating alone out of embarrassment, and feeling disgusted or guilty afterward.
Because there’s no purging, BED is often associated with weight gain over time, though people at any weight can have it. The emotional distress around bingeing is a core feature of the diagnosis, not just the eating behavior itself.
Avoidant/Restrictive Food Intake Disorder (ARFID)
ARFID was added to the diagnostic manual more recently and is sometimes called “selective eating disorder.” It involves an extremely limited diet, but unlike anorexia, there’s no distress about body weight or shape. Instead, the restriction comes from one or more of three drivers: a lack of interest in eating, anxiety about consequences of eating (like choking or vomiting), or strong sensory aversion to certain colors, textures, tastes, or smells of food.
Someone with ARFID might eat only a handful of “safe” foods. The consequences can include significant weight loss, nutritional deficiencies, constipation, abdominal pain, and low body temperature. In children, ARFID can interfere with normal growth and development. It’s distinct from ordinary picky eating because it’s severe enough to affect a person’s health or daily functioning.
Pica
Pica involves persistently eating non-food substances like dirt, chalk, paper, ice, hair, or paint chips. To qualify as pica, the behavior has to be inappropriate for a person’s developmental stage (toddlers mouthing objects doesn’t count) and can’t be part of a culturally accepted practice. Pica sometimes occurs alongside intellectual disabilities, autism spectrum disorder, or pregnancy, but it’s only diagnosed separately when it’s severe enough to need its own clinical attention. The primary risks are poisoning, intestinal blockages, infections, and nutritional problems depending on what’s being consumed.
Rumination Disorder
Rumination disorder involves repeatedly regurgitating food after eating, over a period of at least one month. The regurgitated food may be re-chewed, re-swallowed, or spit out. This isn’t caused by a gastrointestinal condition like acid reflux or a structural problem. It also can’t be diagnosed if it only happens during the course of anorexia, bulimia, BED, or ARFID. Rumination disorder can occur at any age but is most commonly identified in infants and people with intellectual disabilities. It can lead to malnutrition and weight loss when food is consistently spit out rather than re-swallowed.
Other Specified Feeding or Eating Disorder (OSFED)
OSFED is sometimes treated as a catch-all, but it’s a formal diagnosis in its own right and actually covers five distinct subcategories:
- Atypical anorexia nervosa: All the features of anorexia, including significant weight loss and restrictive behavior, but the person’s weight remains within or above a normal range. The medical and psychological consequences can be just as serious as typical anorexia.
- Purging disorder: Recurrent purging (vomiting, laxatives, diuretics) to influence weight or shape, but without binge episodes. This distinguishes it from bulimia.
- Night eating syndrome: Repeated episodes of eating after waking from sleep, or excessive food consumption after the evening meal, with full awareness of the eating. It’s linked to disrupted sleep patterns and significant distress.
- Subthreshold bulimia nervosa: Binge-purge cycles that meet all criteria for bulimia except they occur less frequently or for a shorter duration than the diagnostic threshold requires.
- Subthreshold binge eating disorder: Binge episodes that meet all criteria for BED except they happen less often or over a shorter time period than the full diagnosis requires.
OSFED is not a “mild” diagnosis. Studies consistently find that people with OSFED experience levels of distress, medical complications, and impairment comparable to those with the better-known disorders.
Who Is Affected
Eating disorders affect people of every age, gender, and background, but they most commonly appear during adolescence and young adulthood. The lifetime prevalence is roughly twice as high in women (8.6%) as in men (4.1%), though eating disorders in men are widely underdiagnosed. Since the COVID-19 pandemic began, several countries have reported increases of up to 40% in eating disorder cases among children and adolescents ages 6 to 18.
There is also an unspecified feeding or eating disorder (UFED) category used when a clinician determines an eating disorder is present but chooses not to specify which criteria are or aren’t met. This brings the total number of diagnosable categories to eight, though UFED functions more as a clinical placeholder than a distinct condition.