Everything You Need to Know About Baby Formula

mom and baby shopping for formula

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Thanks to science, baby formula has come a long way over the past century. Today, U.S. manufacturers offer an array of vitamin and nutrient-rich formulas for parents and care providers to choose from.

Now, there are also special formulations for babies with specific health needs, allergies, and intolerances. Choosing to formula-feed your baby is a safe and nutritional option, and there also are some benefits to doing so. Learn about baby formula so when it comes time to feed your baby, you'll be well-informed and confident with your choice.

What Is Baby Formula?

Formula is a special dietary food that simulates breast milk specifically for infants. Baby formula can be a replacement for breast milk or used to supplement it. Infant formulas are available in three forms.

  • Powdered: Each scoop of powdered formula must be mixed with water (ensure water is safe by boiling it and letting it cool). This is the least expensive type of infant formula.
  • Concentrated liquid: Like powdered, this type of formula must also be measured and mixed, according to the provided instructions, with safe water.
  • Ready-to-use formula: Ready-to-use formula is the most convenient type of infant formula as it doesn't need to be mixed with water.

What Is Baby Formula Made of?

The contents of baby formulas vary based on brand. However, the majority of infant formulas purchased and consumed are cow milk-based. Specialized formulas are also available for premature infants and babies who have specific medical conditions.

Cow's Milk Protein-Based Formulas

Most commonly, baby formula is cow's milk-based with nutrients added to mimic those found in breast milk. Most babies thrive on milk-based formulas. Some babies are allergic to the proteins in cow's milk, so they may require other types of infant formula.

Soy-Based Formulas

Soy-based formulas can be useful for babies with specific metabolic needs. Note that some babies who have an allergy to cow's milk might also have a soy milk allergy. 

Protein Hydrolysate Formulas

Protein hydrolysate formulas are designed for babies who don't tolerate cow's milk or soy-based formulas. These types of infant formulas contain protein that's been partially or extensively hydrolyzed (broken down) into smaller sizes than those found in other infant formulas. Extensively hydrolyzed formulas are an option for babies who have protein allergies.

What Else Is in Baby Formula?

Though ingredients vary by brand, the FDA determines nutrient specifications that meet the nutritional needs of infants (children under the age of 12 months).

Oftentimes, manufacturers set their products’ nutrient levels above the FDA minimum specifications. They also add additional nutrients at levels that will ensure their formulas meet their label claims throughout the entire shelf-life of their product. Infant formulas may contain some of the following necessary nutrients.

  • Vitamins: Biotin, choline, inositol, niacin, thiamine, riboflavin, pantothenic, Folic acid, and vitamins A, B6, B12, D, C, E, and K
  • Minerals: Calcium, copper, chloride, iodine, magnesium, phosphorus, potassium, selenium, sodium, and zinc
  • Nutritional supplements: Fatty acids, protein (such as amino acids), probiotics, and linoleic acid
  • Additional ingredients: Lactose (a natural sugar found in milk) and plant-based oils

How Formula Differs from Breast Milk

Infant formula is the best alternative to breast milk, mimicking it nutritionally with vitamins and minerals designed to meet babies' needs. Though well-rounded and nutritious, baby formula isn't an exact replica.

For example, baby formula is thicker in texture and may be more challenging to digest than breast milk. This can result in gas and firmer bowel movements than in breastfed babies.

Manufactured formulas are not as complex as breast milk, which changes naturally to meet the baby's evolving needs. Breast milk also contains antibodies that provides babies with added protection against infection and illness. These antibodies are naturally produced and are therefore not found in infant formulas.

Whichever way you choose to feed your baby—whether it's with breast milk, infant formula, or a combination of the two—the most important thing is that your baby is well-fed, well cared for, and well-loved.

Reasons Parents Choose Formula

The American Academy of Pediatrics (AAP) recommends breast milk as the best nutritional choice for infants. But this doesn't mean breastfeeding is the best decision for everyone.

From personal preference to health-related reasons, there are a variety of influences that lead parents to formula-feed their babies. Dina Kulik, MD, a pediatrician and founder of Kidcrew Medical, described some of these factors.

"Some new parents use formula as it can be convenient and easier for other caregivers to feed," she explained. "Some parents do not have enough breast milk and therefore supplement with formula, or move to formula entirely if the breastfeeding experience is too challenging or stressful."

There are many benefits to formula-feeding. Other family members can share in the bonding experience of feeding the baby and partners can help out with nighttime feedings.

Scheduling feedings may also be easier; formula-fed babies don't need to eat as often as baby formula takes longer to digest. They can also be fed at any time by anyone.

Selecting the Best Baby Formula

If a baby formula is on the shelves in grocery stores and pharmacies, it is FDA-approved and is considered safe for a baby. But not every formula will work well for every baby, so browse the options, speak to your baby's healthcare provider, and see how it goes.

Your baby will likely be just fine with the formula you select. You can always experiment with different types and brands as needed.

"Most babies tolerate cows milk-based formula, and rarely do we need to offer an alternative," Dr. Kulik says. "Some babies have cow's milk protein Intolerance and have GI upset, or even bloody stools when they ingest cows' milk. These babies benefit from a specialized hydrolyzed formula."

If your baby doesn't seem to be tolerating their formula well, Dr. Kulik suggests reaching out to your healthcare provider to rule out any medical causes and to discuss other formula options.

Safe Use of Baby Formula

There are some safety measures to keep in mind when choosing formula feeding. Firstly, the shelf-life of baby formula is usually one year. After that, nutritional content begins to break down. Experts strongly advise against buying and using expired formula.

It is important to ensure that the water you are using is safe. Cold water that has been boiled and left to cool is generally recommended when using powder and concentrated infant formula.

If you choose to warm the formula, ensure you aren't heating it too much. Place a formula-filled bottle in a bowl of warm water and let it stand for a few minutes. Then, test the temperature by putting a few drops on the back of your hand or your wrist.

Dr. Kulik advises parents to always make sure to follow the manufacturers' directions to ensure the mixture is not too diluted or too concentrated when preparing a bottle.

It is not advisable to make your own formula or to feed your infant plain cow's milk, soy milk, or any other non-infant safe formula.

In general, experts recommend weaning your baby off of formula and onto full-fat dairy milk at around 12 months of age. Speak to your healthcare provider when it's time to wean your baby off formula.

A Word From Verywell

Formula is designed to nourish and support your baby's growth. Whichever formula you choose, your baby is bound to thrive. In the rare instance that a certain formula is not quite right for your baby, don't worry; there are plenty of alternatives. Your child's pediatrician is there to support you and your baby when exploring alternate options.

When it comes to parenthood, you want your child to have the best possible start in life. Infant formula is a safe and balanced way to give this to your baby.

4 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. Food and Drug Administration. Questions and answers for consumers concerning infant formula.

  2. KidsHealth. Formula feeding FAQs: Starting solids and milk (for parents).

  3. Centers for Disease Control and Prevention. Recommendations and benefits.

  4. American Academy of Pediatrics. Is homemade baby formula safe?.

By Shannon Day
Shannon Day is a freelance writer specializing in parenting, lifestyle, and women's humor. She has been published in several online parenting and lifestyle sites as well as in print. Shannon is also the co-author of Martinis & Motherhood: Tales of Wonder, Woe & WTF?!