IU D₃, Group 2: 3600 IU vitamin D₂ + 400 IU D₃.

Study 3: Group 1: 400 IU D₃ for mothers + 300 IU D₃ for infants, Group 2: 6400 IU D₃ for mother.

improvement in maternal vitamin D status translated into increases in the vitamin D activity in the milk, but it did not reach 400 IU/L. The 2000 IU group had a mean milk ARA of 69.7 +/− 3.0 IU/L. Mothers in the 4000 IU group had a mean milk ARA of 134.6 +/− 48.3 IU/L. Infants experienced a significant improvement in 25(OH)D levels in both groups, though still insufficient. Study 3 found that mothers receiving 6400 IU/day for 6 months had an increase in milk ARA from 82 to 873 IU/L. This increase in vitamin D supply to the infant achieved infant vitamin D status equal to that observed with direct infant supplementation of 300 IU/day. Mothers demonstrated significant improvement in vitamin D status. No toxicity was observed in mothers or infants throughout the 6 month study period.

Thiele DK, Senti JL, Anderson CM. Maternal vitamin D supplementation to meet the needs of the breastfed infant: a systematic review. J Hum Lac. 2013, 29:163-70.

Reference [1]

Systematic Review

Positive

3 articles were reviewed

Study 1: Group 1 Maternal supplement 2000 IU vitamin D/day (400 as D₃ and 1600 as D₂). Group 2 Maternal supplement 4000 IU/day (400 as D₃ and 3600 as D₂).

Study 2: Group 1 Maternal supplement 400 IU vitamin D₃/day, infants received 300 IU vitamin D₃. Group 2 Maternal supplement 6400 IU vitamin D₃/day; infants received a placebo.

Study 3: Group 1 Maternal supplement 2000 IU vitamin D₂/day. Group 2 Maternal supplement 60,000 IU vitamin D₂ monthly. Infants received 400 IU vitamin D₂/day.

Maternal and infant serum 25(OH)D levels increased in direct relationship to maternal vitamin D intake. Maternal vitamin D supplementation during lactation has an equivalent effect on infant 25(OH)D status as direct infant supplementation but also the potential to benefit both mother and child. There is no evidence to suggest that maternal vitamin D supplementation that results in physiologic 25(OH)D levels in the mother and breastfeeding infant lead to any ill effects, as demonstrated by no change in vitamin D toxicity markers.

Dawodu A, Tsang RC. Maternal vitamin D status: effect on milk vitamin D content and vitamin D status of breastfeeding infants. Adv *Nutr. 2012, 3:353-61.

Reference [5]

Narrative Review

Negative

3 studies reviewed

Study 1: Group 1 Maternal supplement 2000 IU vitamin D/day. Group 2 Maternal supplement 1000 IU vitamin D/day. Group 3 No maternal supplementation; infants recieved 400 IU/day.

Study 2: Group 1 Maternal supplement

High-dose supplementation of 4000 IU/day and 6400 IU/day of vitamin D in healthy lactating mothers can increase the vitamin D concentration of milk to a level that supplies adequate vitamin D intake for the breastfeeding infant even though both mother and infant were limited in sunlight exposure. Vitamin D deficiency in exclusively breastfed infants appears to be an underdiagnosed public health problem in many countries and that rickets may be an underrepresentation of the magnitude of vitamin D deficiency. Multiple studies from the US and Europe show that supplementation of breastfeeding infants with 400 IU/day of vitamin D is sufficient to prevent