If you have a baby under one year, it's pretty common knowledge that milk is one of those off limit foods. It's in the same category as most berries, nuts, honey and egg whites. Why then, can babies eat cheese, yogurt, cottage cheese, and in my daughter's case...ice cream? Hey, I wanted to celebrate her first tooth as a sweet tooth. But I digress...
Back to the milk issue. From everything I've read there are several reasons why babies can have cow's milk products but not cow's milk. For one, the lactose is taken out of milk products as they are made into other products. (Forgive me, I don't know all the technical terms.) Milk, on the other hand, obviously still has the lactose in it. Lactose can be tough on little bellies to digest and therefore it's recommended babies under one year of age avoid cow's milk.
The other major reason to steer clear of cow's milk is so it doesn't replace breastmilk or formula. Breastmilk is widely considered the top nutritional choice, but formula also has the right nutrients in it. Cow's milk is for...well, the cows. It can't properly support the fast rate of growth and development in human babies. The fear is that if a child is given cow's milk before a year, it will replace the necessary breastmilk and/or formula.