Serum zinc levels in youth with avoidant/restrictive food intake disorder and anorexia nervosa: Clinical correlation with weight and psychopathology.

Background: Avoidant/restrictive food intake disorder (ARFID) and anorexia nervosa (AN) are characterized by restrictive eating and micronutrient deficiencies. While zinc deficiency has been identified in AN, zinc level in ARFID has not been systematically assessed.
Aim: Examine serum zinc levels and their association with eating pathology, psychopathology, and executive functioning in youth with ARFID and AN.
Methods: This study included 28 adolescents ( M _age  = 13, 75% female) receiving treatment for ARFID ( n  = 13) and AN ( n  = 15). Demographic data and intake mood metrics were obtained via chart review. Participants completed the Delis-Kaplan Executive Functioning Systems and their mothers completed the behavior rating inventory of executive function (BRIEF-2). Zinc level was collected via blood draw. Independent samples t -tests, Pearson's chi-square, and Pearson's correlations were used to evaluate between-group differences and the relationship between zinc level and clinical correlates.
Results: No between-groups differences emerged in zinc levels, though half the sample demonstrated low levels for their ages. No significant correlations were found between zinc level and demographic data, mood measures, or executive functioning tasks. AN had relatively lower zinc levels, higher eating pathology, and anxiety, though ARFID had a longer duration of illness. Correlations between zinc and BRIEF-2 scores were mixed.
Conclusion: This is the first study to systematically assess zinc levels in ARFID. While there were no group differences for zinc levels, 50% of the sample had low zinc levels. Zinc level did not correlate with higher psychopathology. Monitoring zinc levels throughout treatment in the context of anabolic processes can inform treatment strategies.