According to the American Psychiatric Association–

“Eating disorders are behavioral conditions characterized by severe and persistent disturbance in eating behaviors and associated distressing thoughts and emotions. They can be severe conditions that affect physical, psychological, and social functioning. Types of eating disorders include anorexia nervosa, bulimia nervosa, binge eating disorder, avoidant restrictive food intake disorder, other specified feeding and eating disorder, pica, and rumination disorder.”

The DSM5 classifies eating disorders in the following categories:

Other Specified Feeding and Eating Disorders

This diagnostic category includes eating disorders or disturbances of eating behavior that cause distress and impair family, social, or work function but do not fit the other types listed here. In some cases, this is because the frequency of the behavior does not meet the diagnostic threshold (e.g., the frequency of binges in bulimia or binge eating disorder) 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 fear of fatness are consistent with anorexia nervosa, but 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 high 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 recently defined eating disorder that involves a disturbance in eating resulting in persistent failure to meet nutritional needs and extreme picky eating. In ARFID, food avoidance or a limited food repertoire can be due to one or more of the following:

• Low appetite and lack of interest in eating or food.
• Extreme food avoidance is based on sensory characteristics of foods, e.g., texture, appearance, color, and smell.
• Anxiety or concern about consequences of eating, such as fear of choking, nausea, vomiting, constipation, an allergic reaction, etc. The disorder may develop in response to a significant adverse event such as an episode of choking or food poisoning followed by the avoidance of an increasing variety of foods.

The diagnosis of ARFID requires that difficulties with eating are 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; regular dieting; cultural practices, such as religious fasting; or developmentally normal behaviors, such as toddlers who are picky 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 person’s age, 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, a nutritionist, and others.