Because breast milk produced by most lactating mothers is a…

Because breast milk produced by most lactating mothers is a poor source of vitamin D, breastfed infants should receive a daily 10-microgram (400 I.U.) supplement of vitamin D beginning at birth. Formula-fed newborns should receive a daily 10-microgram (400 I.U.) supplement of vitamin D until their intake of formula averages one liter (or about 4 cups) daily.