Cognitive-behavioral Therapy vs. Nutrition Counseling for Avoidant/Restrictive Food Intake Disorder Part II

Inclusion Criteria: * Males and Females ages 10-18 years old * Current ARFID assessed via Feeding and Eating Disorders Model from the "Enhanced" Structured Interview for DSM-5 (SCID-5) * Normal TSH or free T4 levels to rule out thyroid disease as cause of symptoms inclusionary for randomization * Negative celiac screening panel indicating no active celiac disease as cause of symptoms inclusionary for randomization * Fluency and literacy in English Exclusion Criteria: * Patient requires weight restoration treatment (e.g., \< 5th percentile of BMI, height, or weight for sex and age; patient has fallen off individual growth trajectory; patient's medical providers have recommended weight restoration) such that 15 sessions of CBT-AR is not appropriate * Pregnancy, breastfeeding, or recent initiation/cessation of estrogen-containing systemic contraceptives within 8 weeks of the pre-treatment study visit (as these could impact neuroimaging) * Current/history of psychosis via Mini-International Neuropsychiatric Interview child/adolescent version (MINI KID) * Substance/alcohol use disorder (active within the past month) via MINI KID * Medical instability requiring inpatient care according to the American Psychiatric Association 2006 treatment guidelines for eating disorders * Laboratory abnormalities indicating a need for higher level of care (assessed by complete blood count and comprehensive metabolic panel) exclusionary for randomization * Complete lack of oral intake (suggesting a need for inpatient care) * Tube feeding (suggesting a need for tube weaning) Significant weight/shape concern-motivating eating pathology as evidenced by a global Eating Disorders Examination Questionnaire (EDE-Q) score greater than 4 * Active suicidal ideation with intent or plan via the 5-item Self-Injurious Thoughts and Behaviors Interview-Revised (SITBI-R) * Contraindications to MRI * History of major gastrointestinal tract surgery or serious medical condition (e.g., cancer) * Medical history of intellectual disability * Illiteracy