Saw this article
|It’s best to stick with breast milk until your child is a year old because babies cannot properly digest the protein in cow’s milk.
Would this be worth writing an e-mail to? They don't cite any sources. It would have been nicer had they said that it is best to stick with breast milk for at least one year and beyond that until baby is ready to wean, etc. etc.
ETA: I do like that they recommend making your own baby food
I think the problem is that she uses the word "wean" the way it's used in the UK and other countries, which means "introducing other foods other than breastmilk, thus having the baby eat other foods in addition to breastmilk." In the US, it tends to mean "stop breastfeeding completely"
She does say:
"It’s best to stick with breast milk until your child is a year old because babies cannot properly digest the protein in cow’s milk. Additionally, cow’s milk does not contain as many necessary nutrient as breast milk and it contains minerals that could damage his developing kidneys."