The Effects of Vitamin D Supplementation During Infancy on Growth During the First 2 Years of Life

Abstract Context The relationship between maternal and infant vitamin D and early childhood growth remains inadequately understood. Objective This work aimed to investigate how maternal and child 25-hydroxyvitamin D (25[OH]D) and vitamin D supplementation affect growth during the first 2 years of life. Methods A randomized, double-blinded, single-center intervention study was conducted from pregnancy until offspring age 2 years. Altogether 812 term-born children with complete data were recruited at a maternity hospital. Children received daily vitamin D3 supplementation of 10 μg (group 10) or 30 μg (group 30) from age 2 weeks to 2 years. Anthropometry and growth rate were measured at age 1 and 2 years. Results Toddlers born to mothers with pregnancy 25(OH)D greater than 125 nmol/L were at 2 years lighter and thinner than the reference group with 25(OH)D of 50 to 74.9 nmol/L (P