Vitamin A in pediatrics: An update from the Nutrition Committee of the French Society of Pediatrics

Abstract

VitaminA (retinol) fulfills multiple functions in vision, cell growth and differentiation, embryogenesis, the maintenance of epithelial barriers and immunity. A large number of enzymes, binding proteins and receptors facilitate its intestinal absorption, hepatic storage, secretion, and distribution to target cells. In addition to the preformed retinol of animal origin, some fruits and vegetables are rich in carotenoids with provitaminA precursors such as β-carotene: 6μg of β-carotene corresponds to 1μg retinol equivalent (RE). Carotenoids never cause hypervitaminosisA. Determination of liver retinol concentration, the most reliable marker of vitaminA status, cannot be used in practice. Despite its lack of sensitivity and specificity, the concentration of retinol in blood is used to assess vitaminA status. A blood vitaminA concentration below 0.70μmol/L (200μg/L) indicates insufficient intake. Levels above 1.05μmol/L (300μg/L) indicate an adequate vitaminA status. The recommended dietary intake increases from 250μg RE/day between 7 and 36months of age to 750μg RE/day between 15 and 17years of age, which is usually adequate in industrialized countries. However, intakes often exceed the recommended intake, or even the upper limit (600μg/day), in some non-breastfed infants. The new European regulation on infant and follow-on formulas (2015) will likely limit this excessive intake. In some developing countries, vitaminA deficiency is one of the main causes of blindness and remains a major public health problem. The impact of vitaminA deficiency on mortality was not confirmed by the most recent studies. Periodic supplementation with high doses of vitaminA is currently questioned and food diversification, fortification or low-dose regular supplementation seem preferable.