Choosing Baby Formula

Medically Reviewed by Amita Shroff, MD on November 28, 2022
6 min read

Soy? Whole milk? Hypo-allergenic? Most large supermarkets contain a bewildering array of baby formula choices. Some infant formulas are iron fortified; others contain the fatty acids DHA and ARA. Some are based on soy or cow’s milk; others are made for babies with lactose intolerance. Some are even low in sodium.

How do you choose the right baby formula from this abundance? First, it helps to understand a few infant formula basics.

Although breast milk offers newborns all the nutrition they need, not every mom can or chooses to breastfeed. And, moms who do breastfeed may find that supplementing with infant formula is a practical alternative if they go back to work or when someone else feeds the baby.

Commercially prepared baby formulas are FDA-regulated to provide babies all the nutrients they need. They come in three main forms:

  • Powders. The least expensive option, these are usually mixed with water - one scoop to two ounces of water.
  • Liquid concentrates. Pricier than powders, these are generally diluted with an equal part of water.
  • Ready-to-use baby formulas. Often the most expensive and convenient, ready-to-use formulas can be poured straight into baby’s bottle.

The three forms of formula -- powders, concentrates, and ready-to-use -- are based on different ingredients:

Milk-based baby formulas

Made with cow’s milk, vegetable oils (for fat calories), vitamins, and minerals -- and usually iron-fortified (as recommended by the American Academy of Pediatrics) -- milk-based formulas are appropriate for healthy, full-term babies.

Soy-based baby formulas

Made with soy protein, vegetable oils, corn syrup and/or sucrose (for carbohydrates), and sometimes iron, these formulas are good for babies with lactose intolerance who can’t take milk-based formulas, or those who have allergies to the whole protein in cow’s milk or are on a vegetarian-based diet. Soy infant formulas aren’t recommended for low-birth-weight or preterm babies. Keep in mind that there may be some cross reactivity between soy and milk formulas, especially if the baby is allergic to milk-based formulas.

Specialty baby formulas

This is a big category, comprising a range of products -- infant formulas for low-birth-weight babies, low-sodium formulas for babies who need a restricted salt intake, and formulas thickened with rice starch for babies with reflux.

"Predigested," or hydrolyzed protein formulas, are made for babies who can’t tolerate or have allergies to the whole proteins in cow’s milk and milk-based formulas. Others are for babies with medical conditions that keep their bodies from processing certain proteins or fats.  

Infant formulas enriched with DHA and ARA omega fatty acids from algae have also found their way into the packed baby formula aisle. These fatty acids appear to help baby's brain and nerve development and improve vision.

Some formulas also have probiotics, the “good” bacteria that live in the gut and are in some yogurts. Probiotics give formula-fed babies the same bacteria that breastfed babies have, to keep their intestines healthier. Others have prebiotics, which are carbs that help the good bacteria stay and grow in your baby’s gut.

With all those choices, how can you figure out what’s best for your child?

Begin by asking your baby’s pediatrician for recommendations. You may also have a chance to sample a wide range of baby formulas, as moms often go home from the hospital with free baby formula or coupons.

No matter which baby formula you start with, it helps to know that all formulas made in the United States meet strict FDA guidelines for nutrition, so your infant will probably do just fine on any of them. Whichever baby formula you choose, be sure to check its expiration date and don’t buy damaged cans or bottles.

Sometimes you may need to change the formula your baby drinks. Reasons for switching baby formula include food allergies, a baby’s need for more iron, extreme fussiness, or diarrhea.

These and other symptoms can also be signs of something unrelated to baby’s formula. In that case, a change may not help or could make baby’s symptoms worse. That’s why you should always talk to your baby’s doctor before changing infant formulas.

Call your doctor if your baby has any of these symptoms:

What about switching to follow-up formulas when your baby gets older? Geared for babies 4 to 12 months old, these formulas have more calories and nutrients than regular infant formulas, but again, this change may not be right for your baby. Talk to your pediatrician before trying them.

In the winter of 2008, several news stories came out about melamine -- a synthetic chemical used to produce fertilizers, pesticides, and cleaning products -- in baby formula. Should you be concerned?

If you are using formula made in the U.S., the short answer is: no. Most of the reported health problems were connected to a few baby formulas made in China. In the United States, the FDA doesn’t allow melamine to be used as a food ingredient, so there is no risk of it in baby formulas manufactured in the U.S.

To find out the latest about melamine and food products, visit the FDA website.

Now that you have the basic formula facts, here are some quick tips for safe and effective feeding with formula.


  • Feed your newborn as much baby formula as they want, but don’t force them to finish a bottle they are no longer interested in. Most newborns will eat about 2 or 3 ounces every 2-3 hours.
  • Read the instructions on your baby’s formula to find out exactly how much water to add to concentrates and powders. Adding too little water can lead to diarrhea and dehydration.
  • Don’t “stretch” your budget by watering down infant formula or breast milk. Not only will baby get too few nutrients, but there’s also the small but serious risk of “water intoxication.” This over-consumption of water can disturb baby’s electrolyte balance, resulting in seizures or brain damage. Food pantries, social service agencies, and county health departments can supply formula or funds for caregivers who cannot afford baby formula.
  • Feed your baby a little less formula and more slowly than you have been if they have a lingering problem with spitting up. Always keep the baby upright after feeding them. You might also try limiting active playtime after feeding.
  • Don’t give cow’s milk to a baby younger than 1 year old. The proteins in cow’s milk infant formulas have been cooked or processed, making them much easier for babies to digest than regular cow’s milk.
  • Give your 1-year-old cow’s milk if they enjoy it, but only whole milk, not reduced-fat or nonfat milk. Neither has the fat or calories a growing toddler needs.


  • Don’t heat baby’s bottle in the microwave. Microwave ovens heat unevenly, creating hot spots in liquids that can burn your baby’s mouth. You can make use of the microwave’s convenience by heating a mug of water in it and then warming the bottle in that mug for a minute or two. Or, heat baby’s bottle to a lukewarm temperature under a warm tap. Check the temperature on your skin before offering it to your baby.
  • Use tap water if it’s safe, or bottled water if you’re not sure. You can also use water that you've boiled for at least a minute and cooled.
  • Sterilize new baby bottles and nipples in boiling water for 5 minutes. The nipples will change color, but they’re still fine to use. After that, simply wash bottles, nipples, and caps in the dishwasher. Or wash them by hand with a bottle and nipple brush in hot, soapy water and rinse very well.
  • Wash your hands with soap before preparing baby’s bottle.
  • Always keep prepared baby formula in the refrigerator until you need it. Read the instructions on the formula container to see how long it may be stored. Generally, a prepared bottle of powdered infant formula must be used within 24 hours, and a prepared bottle of liquid concentrate or ready-to-use formula within 48 hours.
  • Buy generic infant formulas if they’re more affordable for you. Name-brand and generic formulas made in the United States must both meet the same strict FDA guidelines for nutrition and safety.

Talk to your pediatrician if you're unsure which formula to use.