Lactation and vitamin D

Abstract

The resurgence in vitamin D-associated rickets and world-wide description of maternal and infant vitamin D deficiency highlights the need for global maternal and infant vitamin D recommendations and action to ensure vitamin D health during lactation. Direct infant vitamin D supplementation of at least 400 IU/day vitamin D will protect the majority of infants from vitamin D deficiency rickets by maintaining 25-hydroxyvitamin D status above 50 nmol/l regardless of race, season, latitude, or maternal vitamin D status. Additionally, the physiology of breast milk production comprises the mechanism required for the mother to supply vitamin D activity to her infant and, with adequate maternal vitamin D intake, a mother is able to supply her infant with the vitamin D required to match the status achieved with direct infant supplementation. As current multi-center, randomized, controlled trials are underway to identify the maternal vitamin D supplementation associated with safe, effective supplementation of the breastfed infant, studies to more accurately define infant vitamin D health also are occurring. Though the vitamin D status and dose to safely avoid vitamin D deficiency rickets are known, the vitamin D status and/or dose (infant and/or maternal) that optimizes infant bone health or immune function for both short- and long-term outcomes has yet to be identified. Current case series and cohort studies demonstrate that infant vitamin D health may be important in avoiding acute lower respiratory infection and diabetes mellitus type 1.