To avoid developing a vitamin D (vitD) deficiency, The American Academy of Pediatrics and the National Institute of Health currently (2021) recommend that breastfed and partially breastfed infants be supplemented with 400 IU per day of vitD beginning in the first few days of life (https://ods.od.nih.gov/pdf/factsheets/VitaminD-Consumer.pdf).   

A recent study shows that an alternative to providing supplementation directly to the infant is to supplement the mother. (Andrews L et al: Comparison of Infant Bone Mineral Content and Density After Infant Daily Oral VitD 400 IU Supplementation Versus Nursing Mother Oral 6,400 IU Supplementation: A Randomized Controlled Lactation Study. Breastfeed Med. 2022;17(6):493-500. http://doi.org/10.1089/bfm.2021.0281).

Andrews et al Article Summary. Bone mineral content (BMC) and bone mineral density (BMD) of infants were measured to determine effectiveness of vitD supplementation. These parameters were measured for two groups of exclusively breastfed infants. One group of infants, as well as their mothers, received direct vitD supplementation (400 IU vitD₃/day), whereas infants in the other group received no direct vitD, but their mothers were given high-dose supplementation (6,400 IU vitD₃/day).

BMC and BMD did not differ significantly at 1, 4, or 7 months of age between the two groups of infants, showing that high-dose vitD supplementation (6.400 IU/day) of mothers effectively satisfied vitD requirements of the exclusively breastfed infant.

Safety of high-dose supplementation (6,400 IU vitD/day) for the mother and infant.

Evidence has been presented that a 6,400 IU vitD/day supplement given to the breastfeeding mother is safe for both mother and infant (Wagner C, et al : Safety Aspects of a Randomized Clinical Trial of Maternal and Infant Vitamin D Supplementation by Feeding Type Through 7 Months Postpartum. Breastfeed Med. 2020; 15(12):765-775. [http://doi.org/10.1089/bfm.2020.0056]). However, the current upper limit recommended for adults by the National Institute of Health (NIH) is 4,000 IU vitD/day (https://ods.od.nih.gov/pdf/factsheets/VitaminD-Consumer.pdf). Unfortunately, this dose was not examined by Andrews et al to supplement breastfeeding mothers to satisfy vitD requirements of their infants.

Finally, in choosing the vitD supplementation method for infants, it should be mentioned that direct oral supplementation of infants is simple, and when reduction of breastfeeding or its cessation occur, direct oral supplements of vitD at 400 IU/day become necessary for the infant, regardless of the mother’s supplementation.

Robert Peck, President GIFA