How do breast milk and formula differ?
Breast milk contains all the ingredients that a human baby needs to thrive. Formulas based on cow’s milk or soy include many of the same nutrients, but not all. Formula makers cannot duplicate all of the ingredients in breast milk, because some of the ingredients are not known. Breast milk includes antibodies and other immune-system substances that help protect a baby from illness. It contains growth factors, hormones and other substances that help a baby grow and develop at an appropriate rate. Breast milk also contains fatty acids that appear to promote brain development and, possibly, increase intelligence. Some formula makers add two of these fatty acids—DHA (docohexanoic acid) and ARA (arachidonic acid)—to their products. However, the long-term benefits of formula enhanced with these fatty acids are not known. The AAP recommends that all babies, including those who are exclusively breastfed, consume at least 400 international units (IUs) of vitamin D to help prevent a bone-weakeni
