How to choose and prepare the right formula for your baby.


Medical experts say that breastfeeding is the best option for mom and baby. But if breastfeeding isn't the right choice for you, there's no need to worry. Babies can grow up perfectly healthy and happy on infant formula. In fact, formulas today are much more sophisticated than they were when we were babies. Even some breastfeeding moms like to supplement breast milk with infant formula from time to time.

But many new moms today are confused about what type of formula to buy and how to prepare it. Read on to get the lowdown on infant formula.

Buying Formula

Infant formulas are available in three different forms (listed from most expensive to least expensive):

  • Ready-to-feed liquid
  • Concentrate
  • Powder (which comes either in premeasured packets or in a can with a measuring scoop)

The ready-to-feed liquids are the easiest for parents to prepare, which is why they're the most expensive. The opposite is true of powdered formulas -- they require the most work, but are the best bargain.

In addition to coming in different forms, formula also comes in several different types of bases. These are:

Cow's milk

Cow's-milk-based formulas account for about 80 percent of the formula sold in America today. You may wonder how babies can drink cow's-milk-based formula if babies under 12 months of age aren't supposed to drink cow's milk. Actually, these formulas use dramatically altered cow's milk that is perfectly safe for your baby -- the protein is made more digestible, butterfat is replaced by oils or animal fats that are easier on your baby's tummy, and lactose is added to make it more like breast milk.

Cow's milk formulas are also available with added iron. The American Academy of Pediatrics (AAP) recommends that parents give all bottlefed infants from birth to 1 year an iron-fortified formula.


Soy formulas -- which contain a different protein (soy) and different carbohydrate (glucose polymers or sucrose) from cow's milk formula -- are usually only given to babies who are unable to digest lactose. Often, babies who are diagnosed as lactose intolerant are placed on a soy formula for a short time (anywhere from a week to several months) so that their digestive enzymes can return to normal. Your pediatrician will tell you when it's safe to return to milk-based formula.

Occasionally, an infant is placed on soy formula because of a milk allergy. Symptoms of a milk allergy include colic, failure to grow, and blood in his feces. If you have a family history of milk allergies, your pediatrician may recommend getting your newborn on soy formula at birth. Unfortunately, as many as half the infants who have milk allergy are also sensitive to soy milk. Those babies may require a specialized formula.

Soy formulas contain a good source of protein, but they're not quite as good as cow's milk. Some strict vegetarian parents use soy formula because it contains no animal products. But according to the AAP, healthy infants should only be given soy formula when it's medically necessary.

Specialized milk

Specialized formulas are only given to babies who medically require it. It is specifically manufactured for infants with particular disorders or diseases.

It is most commonly fed to babies who are allergic to both cow's-milk-based and soy-based formulas. There also are some specialized formulas made specifically with nutrients for premature babies. Do not give a baby specialized formula without talking to a pediatrician first.


The Food and Drug Administration granted approval for the inclusion of two naturally occurring fatty acids, known as DHA and ARA, in infant formulas in early 2002. This has made formula buying even more confusing for some parents.

DHA and ARA are lipids that are transferred to a fetus through the placenta. But they also appear in a mother's breast milk, and studies show that breastfed babies have higher levels of DHA and ARA in their blood than formula-fed babies. Adding DHA and ARA to formula is an attempt to provide infants with a source of nutrition that was previously only available to breastfed babies.

Recent theories suggest that it may be these higher levels of DHA and ARA that lead to higher IQ scores in breastfed babies. But researchers haven't yet agreed on whether or not adding DHA and ARA will have any long-term effects on a child's development. Some studies have found that babies fed with DHA- and ARA-supplemented formulas have faster cognitive development and visual development than regular formula-fed babies, but other research has not seen this correlation.

More importantly, however, no negative affects of DHA and ARA have been found. But nothing comes without a cost. Formulas that are supplemented with DHA and ARA can be considerably more pricy than traditional formula. If new parents don't mind spending the extra money on DHA- and ARA-supplemented formulas, there's certainly no harm in them. But there's not enough evidence at this time to recommend these supplemented formulas either. It's up to each parent to decide what's right for her baby.

Preparing Formula

Formula preparation varies depending on what type of formula you buy. Regardless, it's very important that you follow the manufacturer's directions exactly. Give your baby too much water and she won't get the calories and nutrients she needs. Give her too little water and she may get too much formula and suffer from diarrhea, dehydration, or abnormal weight gain.

If you bought ready-to feed liquid, there's very little work involved. Just pour the liquid in a sterilized bottle and you're ready to go.

If you bought a concentrate, mix an equal amount of the concentrate and sterile water. If you open a can of concentrate but do not use it all in one feeding, cover the can and leave it in the refrigerator for up to 48 hours.

If you bought a powder, add one scoop of powder for every 2 ounces of water. Then stir the mixture thoroughly to make sure there are no clumps of powder in the bottle. Here's a tip: Use slightly warmed water and the powder will dissolve more easily. Powder is also easily transportable and will not spoil. You can even keep it in a bottle for several days before you add water.

Regardless of what kind of formula you bought and what form it may be in, there are certain things that all bottlefeeding parents need to do when preparing formula:

  • Make sure that all bottles, nipples, and other utensils you use to prepare formula, or to feed your baby, are clean. If the water in your home is nonchlorinated, you can simply place the utensils in boiling water for five to 10 minutes. If your water is chlorinated, you should either wash the utensils in your dishwasher or, if you don't have a dishwasher, soak them in hot tap water with dishwashing detergent and then rinse them in hot tap water.
  • Store any formula that you prepare in advance in the refrigerator. If you don't use refrigerated formula within 24 hours, throw it away.
  • To warm refrigerated or frozen milk, place the container in warm water and rotate it frequently. When you suspect that the milk has reached room temperature, shake a few drops on the inside of your wrist to test it. Avoid thawing milk by leaving it at room temperature -- this can lead to bacterial growth. Also, do not use the microwave for heating bottles. Microwave ovens can heat the milk in the center of the bottle to a much higher temperature than the milk on the outside. The bottle may feel comfortable to your touch, but your baby's mouth could get burned by the heat in the middle. Plus, a report from the American Academy of Pediatrics (AAP) published in the August 2018 edition of Pediatric says microwave heat causes plastics to leak harmful chemicals like BPA and phthalates into food, including infant formula and pumped breast milk.
  • Use thawed milk within four hours after reheating. Never refreeze it.

If you have any questions about what kind of formula might be right for your baby or how it should be prepared, consult your child's pediatrician.

Sources: Caring for Your Baby and Young Child: Birth to Age 5 (Bantam); American Academy of Pediatrics;

All content here, including advice from doctors and other health professionals, should be considered as opinion only. Always seek the direct advice of your own doctor in connection with any questions or issues you may have regarding your own health or the health of others.

American Baby