With my first son, 7 years ago, I didn't do any supplements.
This time, in light of all of the recent research about Vitamin D, I'm thinking of supplementing that at least. I went to Whole foods and saw a fish oil (DHA) supplement including vitamin D for babies, and wondered about this for a EBF baby...I know breastmilk contains DHA I think.
I don't think you're going to overdo it by giving it to him. I give my breastfed seven month old a fish oil with vitamin D. My plan is to give it daily, but honestly, it works out to more like 2-3 days a week.
Midwife (CPM, LDM) and homeschooling mama to:
13yo ds 10yo dd 8yo ds and 6yo ds and 1yo ds