Avoidant/Restrictive Food Intake and Selective Eating in Children: Clinical Profile, Nutritional Deficiencies, and Behavioral Correlates in a Tertiary Pediatric Center

Background: Avoidant/restrictive food intake disorder (ARFID) and selective eating are increasingly recognized in pediatric nutrition, but food selectivity has been predominantly studied in dedicated eating disorder settings and in underweight children, potentially underestimating its prevalence across broader clinical populations. This study aimed to characterize food selectivity as a transdiagnostic feature in children referred to a tertiary pediatric nutrition center, regardless of referral diagnosis or BMI status. Methods: This retrospective observational study included 417 consecutive children and adolescents (median age 9.3 years, IQR 4.1–12.9; 47.5% male) assessed at the General Pediatric Eating Disorders Outpatient Unit of Bambino Gesù Children’s Hospital IRCCS, Rome, Italy, between May 2024 and April 2026. Food selectivity was defined as clinician-documented avoidance of at least one of four food groups (vegetables, fruit, fish, and legumes). Patients were classified as having primary selective eating/ARFID (Group A, n = 141), unrecognized selective eating (Group B, n = 163), or no selectivity (Group C, n = 113). Results: Food selectivity was identified in 293 patients (70.3%), including 70.8% of those referred for obesity or overweight and 50.0% of those referred for eating disorders. Prevalence did not differ across BMI categories (p = 0.554), confirming that selective eating is independent of anthropometric status. Ferritin deficiency showed a significant gradient across groups (Group A 32.2%, Group B 17.9%, Group C 10.8%; p = 0.002). Screen use during meals and ultra-processed food consumption were similarly elevated in Groups A and B and significantly higher than in Group C (p = 0.002 and p < 0.001, respectively), with no difference between the two selective groups. Conclusions: Food selectivity is a transdiagnostic and BMI-independent feature affecting the majority of children referred for pediatric nutritional evaluation. Children with unrecognized selective eating share the same nutritional risks and behavioral correlates as those formally diagnosed with ARFID, supporting the integration of a brief food group avoidance screen into routine nutritional assessment regardless of the primary referral diagnosis.