Micronutrient Status in Children Suffering From Anorexia Nervosa: A Cohort of 349 Patients in a Referral Center for Eating Disorders

ABSTRACT Objective Anorexia nervosa (AN) is a serious illness in which more than half of all deaths are due to malnutrition. Critically low energy and protein intake are known causes of massive weight loss, whereas micronutrient deficiencies due to a low‐calorie food pattern remain poorly characterized in children with AN. Micronutrient deficiencies in AN, such as selenium deficiency, are known to increase anxiety and the risk of suicide. Two large studies in adults highlighted frequent selenium and copper deficiencies; this information is lacking in children. The present study aimed to provide a comprehensive description of the micronutrient status in pediatric AN and evaluate whether deficiencies differ according to AN subtype (restricting, R, binge‐eating/purging, BP). Method A retrospective, single‐center, descriptive study was conducted in a cohort of children with AN who were evaluated at a specialist eating disorders center from 2016 to 2022. Results The sample comprised 349 patients (mean age 14.7 ± 1.8 years); 91.4% had AN‐R, 8.6% BP. Mean weight loss was 18.2% ± 10.7%, and initial BMI was 16.7 ± 1.1 kg/m 2 according to the International Obesity Task Force. At least one micronutrient deficiency was found in 90% of patients; 51.3% experienced multiple deficiencies. The most common were selenium (23.5%), copper (18.4%), and vitamin A (29.1%). The prevalence of deficiencies was similar between AN‐R and AN‐BP, except for potassium and calcium which were significantly lower in AN‐BP. Discussion Micronutrients deficiencies are frequent in pediatric AN with no difference according to subtype. The functional impact and the benefit of supplementation remain to be studied.