food intake disorder should be differentiated fr om factitious disorder or factitious disor-
der imposed on another. In orde r to assume the sick role, so me individuals with factitious
disorder may intentionally describe diets that  are much more restrictive than those they
are actually able to consume, as well as comp lications of such behavior, such as a need for
enteral feedings or nutritional supplements,  an inability to tolera te a normal range of
foods, and/or an inability to participate normally in age-a ppropriate situations involving
food. The presentation may be impressively dramatic and engaging, and the symptoms re-
ported inconsistently. In factitious disorder  imposed on another, the caregive r describes
symptoms consistent with avoidant/restric tive food intake di sorder and may induce
physical symptoms such as failure to gain weig ht. As with any diagno sis of factitious dis-
order imposed on another, the caregiver receives the diagnosis rather than the affected in-
dividual, and diagnosis should be made only on the basis of a careful, comprehensive
assessment of the affected individual, the caregiver, and their interaction. 
Comorbidity
The most commonly observed disorders comorb id with avoidant/restrictive food intake
disorder are anxiety disorders, obsessive- compulsive disorder, and neurodevelopmental
disorders (specifically autism spectrum disorder, attention-deficit/hyperactivity disor-
der, and intellectual disability [int ellectual developm ental disorder]).
Anorexia Nervosa
Diagnostic Criteria
A. Restriction of energy intake relative to requirements, leading to a significantly low body
weight in the context of age, sex, developmental trajectory, and physical health.  Sig-
nificantly low weight  is defined as a weight that is less than minimally normal or, for