
A wide variety of infant formulas are on the market. The majority of them are based on cow’s milk. However, never use regular cow’s milk as a substitute for formula. In processing formula, the milk has been changed dramatically to make it safe for babies. This processing includes treating formula by heat to make the protein in it more digestible.
Also, formula must contain the right amount of carbohydrates, fat and protein to meet baby’s needs. The Food and Drug Administration (FDA) monitors commercially prepared infant formula. Each manufacturer must test each batch of formula to ensure it has the required nutrients and is free of contaminants.
You may come across European formulas sold through the mail, but the formulas don’t meet FDA standards. In 2021, the FDA announced that several European formulas didn’t include adequate iron needed by some infants. Babies born prematurely, at a low birth weight or with certain health conditions can develop iron deficiency anemia if they don’t receive enough iron during infancy. Always choose a formula approved by the FDA in the United States.
Three major types of formula are available, and they typically come in three forms: powdered formula, concentrated liquid formula and ready-to use formula.
- Cow’s milk formulas. Most infant formula is made with cow’s milk that’s been altered to resemble breast milk. This gives the formula the right balance of nutrients — and makes the formula easier to digest. Most babies do well on cow’s milk formula. Some babies, however — such as those allergic to the proteins in cow’s milk or have intolerance to the lactose — may need other types of infant formula. There are lactose free cow’s milk formulas where the lactose has been removed and replaced with a different type of carbohydrate.
- Soy-based formulas. Soy-based formulas can be useful if you want to exclude animal proteins from your child’s diet. Soy-based formulas may also be an option for babies who are intolerant or allergic to cow’s milk formula or to lactose, a sugar naturally found in cow’s milk. However, babies who are allergic to cow’s milk may also be allergic to soy milk.
- Protein hydrolysate formulas. These are meant for babies who have a milk or soy allergy. Protein hydrolysate formulas are easier to digest and less likely to cause allergic reactions than are other types of formula. They’re also called hypoallergenic formulas. Extensively hydrolyzed formulas and amino acid-based formulas contain proteins that have been broken down. They’re less likely to cause an allergic reaction in an infant with an allergy. In addition, you can find specialized formulas that are made for premature infants and babies who have specific medical conditions. These formulas are very expensive and typically should be used only if recommended by your baby’s health care provider.
It’s important to buy iron-fortified infant formula. Your baby needs iron to grow and develop, especially during infancy. If you’re not breast-feeding, using iron-fortified formula is the easiest way to provide this essential nutrient.
Some infant formulas are enhanced with docosahexaenoic acid (DHA) and arachidonic acid (ARA). These are essential fatty acids found in breast milk and certain foods, such as fish and eggs. Some studies suggest that including DHA and ARA in infant formula can help infant eyesight and brain development, but other research has shown no benefit.
In addition, in an effort to mimic the immune benefits of breast milk, some infant formulas now include probiotics — substances that promote the presence of healthy bacteria in the intestines. The data on probiotic-supplemented formulas is limited and long-term benefits or complications of the formula are unknown.
At this point, there’s insufficient evidence to recommend the use of enhanced formulas. In addition, they tend to be more expensive than regular formula. If you think your child might benefit from formula supplemented with probiotics or another substance, talk to your baby’s medical provider for additional information and guidance.
Feeding your baby — whether you choose breast milk or formula — is a time of cuddling and closeness that helps build the connection between you and your baby. Make every feeding a time to bond with your baby and cherish these feedings before your baby is old enough to start feeding himself or herself. That time will come soon enough.

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