There are different types and forms of infant formula; your baby's doctor or clinic can help you choose the right one. The most common formulas are made from specially treated cow's milk and fortified with iron. Regular cow's milk should never be given to children younger than 1 year. Babies cannot digest milk protein properly and it doesn't contain the right amounts of iron or vitamin C for growing infants.
Your health-care provider may recommend a soy formula or other specialized formulas such as those for premature babies. Discuss any feeding changes with your doctor or a registered dietitian. Formulas come in ready-to-use, concentrate and powder forms. Powder is the least expensive. Read the label and follow all mixing instructions carefully.