Filipino Children with High Usual Vitamin A Intakes and Exposure to Multiple Sources of Vitamin A Have Elevated Total Body Stores of Vitamin A But Do Not Show Clear Evidence of Vitamin A Toxicity

BackgroundYoung children exposed to high-dose vitamin A supplements (VAS) and vitamin A (VA)-fortified foods may be at risk of high VA intake and high VA total body stores (TBS).ObjectivesTBS and estimated liver VA concentration were compared among children with adequate or high VA intake and different timing of exposure to VAS, and associations between estimated liver VA concentrations and biomarkers of VA toxicity were examined.MethodsChildren 12-18mo of age (n=123) were selected for 3 groups: 1) retinol intake >600µg/d and VAS within the past mo, 2) retinol intake >600µg/dand VAS in the past 3-6mo, and 3) VA intake 200-500µg retinol activity equivalents (RAE)/d and VAS in the past 3-6mo. Dietary intake data were collected to measure VA intakes from complementary foods, breast milk, and low-dose, over-the-counter supplements. TBS were assessed by retinol isotope dilution, and VA toxicity biomarkers were measured. Main outcomes were compared by group.ResultsMean (95% CI) VA intakes excluding VAS were 1184 (942, 1426), 980 (772, 1187), and 627 (530, 724) µg RAE/d, in groups 1-3, respectively; mean VA intake was higher in groups 1 and 2 compared with group 3 (P1µmol/g liver). There was no evidence of chronic VA toxicity, suggesting that the liver VA cutoff value should be re-evaluated. This trial was registered at www.clinicaltrials.gov as NCT03030339.