Effect of vitamin D supplementation, directly or via breast milk for term infants, on serum 25 hydroxyvitamin D and related biochemistry, and propensity to infection: a randomised placebo-controlled trial

We assessed the effect of vitamin D supplementation on related biochemistry, infection and dentition of the infant. In a double-blind, placebo-controlled trial conducted in Lucknow, India (latitude 26 degrees N), 230 mother -newborn pairs were randomised to receive, for 9 months, 3000 mu g/month oral vitamin D-3 by the mother (group A) or 10 mu g/d by the infant (group B) or double placebo (group C). All babies received 15 min of sun exposure (unclothed) during massage. Infants' median 25-hydroxyvitamin D (25(OH)D) was lower in group C (median 453; interquartile range (IQR) 22-595 nmol/l) than in groups A (median 608; IQR 413-805 nmol/l (P<001)) and B (median 613; IQR 413-753 nmol/l (P<005)) at 35 months. Infant 25(OH)D correlated negatively with infant parathyroid hormone (r -046, P<001). Elevated alkaline phosphatase (>7.5 mu kat/l) was significantly more frequent in group C babies (16 %) than in group A (4 %) or group B (0 %) babies. The number of days with respiratory or diarrhoeal infection by 9 months of age was higher in group C (median 465; IQR 148-733 d) than in group A (median 185; IQR 88-310 d (P<001)) or group B (median 130; IQR 70-285 (P<005)). We conclude that monthly maternal or daily infant supplementation with vitamin D along with sun exposure is superior to sun exposure alone in maintaining normal infant 25(OH)D at 35 months, and provide protection from elevated alkaline phosphatase and infectious morbidity.