母乳
Breast milk also contains much more protein than cow's milk. It contains 60% protein whereas cow's milk contains only 40% protein. Protein is very important for infants because they need more protein per pound than adults do. For the first few months of their life, this protein must come from breast milk or infant formula, it cannot come from cow's milk. One specific protein that breast milk has is lactoferrin, which is bacteriostatic, meaning it prevents the growth of harmful bacteria. Without this protein, the baby cannot produce the immunity that its body desperately needs, resulting in a higher risk of disease and malnutrition. Breast milk provides the best source of protein for an infant.