Vitamin D

The AAP recommends that all children (birth through adolescence) receive 400 IU vitamin D per day. Human breastmilk is a very poor source of vitamin D, usually containing less than 50 IU per quart. This is why the AAP recommends all breastfed infants receive 400 IU per day vitamin D by supplement drops. 

If a mom takes 6400 IU per day, she will supply her nursing infant with plenty of vitamin D thru her milk and will not need to give her infant drops.