Types of Baby Formula
For the vast majority of babies, cow's milk formula is the best choice and the one most often recommended by pediatricians. It is the baby formula that most closely simulates breast milk and is made from simplified cow's milk.
To make cow's milk easier for babies to digest, the carbohydrates, proteins, and fats in the milk have been modified. The milk has also been fortified with vitamins and minerals, including folic acid, zinc and iron. These minerals are found in cow's milk, but in smaller quantities.
Iron-fortified baby formulas are recommended for all babies until they reach their first birthday. Babies who are fed low iron formula are at risk for iron-deficiency anemia because they are not receiving iron from any other source. Low-iron formulas are nutritionally inadequate to meet the needs of a growing infant.
Some parents worry that iron fortified baby formulas cause constipation, baby colic, reflux, or stomach upset. There is no scientific proof showing iron causes any of these ailments. You should not switch to a low iron formula if your baby suffers from one of these ailments without speaking to your doctor.
There are formulas enriched with DHA and ARA—nutrients that are naturally found in breast milk. These nutrients may play important roles in babies' brain and eye development and their addition to formula may benefit formula fed babies. There is no evidence suggesting that these new additives are harmful to babies, but there aren't any long-term studies confirming their safety either. The U.S. Food and Drug Administration (FDA) approved DHA and ARA for use in formula based on short-term studies. Long-term research to monitor the effects of DHA and ARA in baby formula is on-going.
Soy-based baby formulas may be recommended for babies who need to avoid cow's-milk protein or lactose. Soy-based baby formula is also popular for babies in vegetarian families. Soy is a plant-based protein that, like cows' milk, has been modified for easy digestion and has added vitamins and minerals. Babies who are sensitive to lactose may do better on soy-based formulas, but always speak to your doctor first. Nearly half of all babies who are allergic to cows'-milk formula are also allergic to soy formula.
Soy baby formula is not recommended for healthy babies who show no sign of lactose intolerance. Babies don't absorb as much calcium and nutrients from soy formula as they do from cows' milk formula. Soy milk baby formula may help your baby's stomach enzymes return to normal after a case of diarrhea, but it cannot help soothe a colicky baby.
Babies who cannot digest cows' milk or soy-based formula may be switched to a hydrolysate baby formula. Hydrolysate baby formulas are also called hypoallergenic formulas, although it is possible for a child to be allergic to them as well. Hydrolysate baby formulas contain proteins that have been hydrolyzed or broken down to make the digestive process easier.