My son is 3 month now , when i can strat his cow milk ??

A. Your baby has a young digestive system, which means they can't digest milk as easily as they can digest breast milk or formula. Giving cow's milk or other milk instead of formula or breast milk before age one can stop your baby from growing well.Beyond digestion. Also, cow's milk contains high concentrations of protein and minerals, which can stress a newborn's immature kidneys and cause severe illness at times of heat stress, fever, or diarrhea. In addition, cow's milk lacks the proper amounts of iron, vitamin C, and other nutrients that infants need.