What’s in Infant Formula?

Yvette Zhu
July 3, 2020

We at SimpliFed believe that you gotta do what you think is best for you and your baby. While we try to #normalizebreastfeeding, we also recognize that infant formula is the bomb.dot.com as well. According to the CDC, 75% of moms are using infant formula by the time their babies are 6 months old. We believe that infant feeding shouldn’t be an either/or thing with breastfeeding and infant formula. You gotta do what is best for you and we are here to help you make an informed decision. So what’s in infant formula?

First things first: FDA Regulation

Commercially prepared infant formulas are regulated by the U.S. Food and Drug Administration (FDA) under the Federal Food and Drug and Cosmetics act (FFDCA). Regulations outlined in section 412 of the FFDCA in the 21 CFR 106 and 107 demand that all infant formulas marketed in the U.S. must meet the requirements of the minimum concentrations of 29 essential nutrients [1]. In addition, the FDA inspects all manufacturing plants to ensure they stand up to the rigorous monitoring controls, meet the safety regulations, and keep detailed records of every batch made [2]. With very intense regulations and monitoring (and they should be!), infant formulas are probably the safest food you could get in the U.S. But that being said, there is still a lot of flexibility and variation in the ingredients of different infant formula brands. All infant formulas on the market have passed the regulations and numerous testings to guarantee the babies will gain weight, grow, and will not need supplemental nutrition; but they can still differ in their components.

So what exactly is in infant formula?

An infant’s diet is quite boring in the first months of their lives, meaning the only food a baby eats is milk (either breast milk, infant formulas, or a combination of both). Due to this simple diet, infant formulas are made to represent mom’s breast milk as closely as possible and to contain all nutrients necessary for a baby’s growth and development (as much as current nutritional and food science allows). Just like breast milk contains proteins, fats, carbohydrates, vitamins, and minerals, infant formulas contain the same categories of nutrients.

For sources of proteins, infant formulas are commonly cow milk protein-based or soy-based. Both human and cow milk have two main subgroups of proteins, casein and whey. Cow milk contains about 80% casein and 20% whey; human milk contains about 40% casein and 60% whey. In general, it is recommended for young infants, particularly under 6 months of age, to choose a whey based starter formula. According to the Mayo Clinic, most babies do well on cow milk-based formula while some babies, like those allergic to the proteins in cow’s milk, could choose other types such as soy-based formulas [4]. The benefits between the two are comparable as many studies have shown that the growth and physical development of babies fed soy-based formula is similar to those fed milk-based formulas [6]. When researching different infant formulas, you may also see something called protein hydrolysate, which is sometimes labeled as hydrolyzed formulas. This means that the proteins are either partially or completely broken down into smaller, more digestible pieces. Hydrolyzed formulas, also identified as hypoallergenic formulas, are targeted to babies who do not tolerate cow milk or soy-based proteins well. It is often mentioned that feeding infants partially or extensively hydrolyzed formula prevents/delays atopic diseases such as eczema. However, the American Academy of Pediatrics review of current research findings found no solid evidence of this [7].

For fats or lipids, higher coconut oil content is preferred over other types such as palm olein oil. Coconut oil contains triglycerides and calcium that are more easily absorbed than the ones found in palm olein oil, which is especially important for babies that are born early or can’t digest fats very well.

For carbohydrates, lactose is preferred over other types such as corn syrup solids, maltodextrin, glucose syrup, or sucrose, as lactose is the most abundant form of carbohydrates found in human breast milk.

Other ingredients of infant formulas include vitamins and minerals. Since the contents are regulated by the FDA, there is not much variation in the amount of vitamins and minerals in baby formulas.

Most formulas these days, except for the organic brands, also contain docosahexaenoic acid (DHA) and arachidonic acid (ARA). DHA and ARA are types of fat called omega-3 fatty acids that are found in the breast milk. Although they are not essential fatty acids, they are added to mimic the breast milk and because some research has suggested increased eyesight and brain development with added DHA and ARA.

In addition, many formulas include pre and probiotics, both of which are found in breast milk. Probiotics are live, good bacteria that could move into the baby’s gut, while prebiotics are food for the good bacteria to grow. Inclusion of pre and probiotics in infant formula may be useful for allergy prevention, however the research and evidence of these positive effects are limited and not conclusive. In particular, special caution should be taken for immunocompromised infants [8]. Make sure to discuss with your pediatrician any specific concerns before choosing any of the infant formulas mentioned above.

Formula has been studied extensively and continues to be improved over the years. While it can never have the exact components that human breast milk has, it meets the nutritional requirements that infants need and for many babies can make sure they are getting the nourishment they need to grow into healthy children whether on its own or in combination with breast milk.

– Kathy Murphy, IBCLC, SimpliFed

Looking at breast milk and infant formula

Take a look at this post with an infant feeding infographic and worksheet to better understand your different feeding options and think through your infant feeding decisions

Research has shown that the composition of breast milk is highly variable and changes to meet the baby’s unique needs as it grows [3, 5]. So if a mom’s breast milk is like “tailored-made” for her baby, commercial infant formulas are like the “one size fits all.” When regulating the contents of each ingredient in infant formulas, researchers and scientists often use the average values of the components found in breast milk. Moreover, certain substances in breast milk such as antibodies and probiotics are unique to the mom and her baby. Although formulas have been constantly changing to better mimic breast milk, these bioactive components still can’t be duplicated or commercially produced to be added to infant formulas.  Despite this, infant formulas have all of the necessary nutrition for your baby to thrive and grow. Whether your baby uses breast milk or infant formula, we at SimpliFed believe in both #normalizingbreastfeeding and #fedisbest.


  1. “CFR – Code of Federal Regulations Title 21.” Accessdata.fda.gov, www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=107&showFR=1
  2. Young, Bridget. “Best Baby Formula.” Baby Formula Expert, 24 Jan. 2019, babyformulaexpert.com/best-baby-formula-series/
  3. Breastfeeding vs. Formula Feeding – Johns Hopkins All Children’s Hospital, www.hopkinsallchildrens.org/Patients-Families/Health-Library/HealthDocNew/Breastfeeding-vs-Formula-Feeding
  4. “Infant Formula: Your Questions Answered.” Mayo Clinic, Mayo Foundation for Medical Education and Research, 20 Dec. 2018, www.mayoclinic.org/healthy-lifestyle/infant-and-toddler-health/in-depth/infant-formula/art-20045782
  5. Andreas, Nicholas J., et al. “Human Breast Milk: A Review on Its Composition and Bioactivity.” Early Human Development, Elsevier, 12 Sept. 2015, www.sciencedirect.com/science/article/pii/S0378378215001772
  6. “Concerns for the Use of Soy-Based Formulas in Infant Nutrition.” Paediatrics & Child Health, Pulsus Group Inc, Feb. 2009, www.ncbi.nlm.nih.gov/pmc/articles/PMC2661347/
  7. Greer, Frank R., et al. “The Effects of Early Nutritional Interventions on the Development of Atopic Disease in Infants and Children: The Role of Maternal Dietary Restriction, Breastfeeding, Hydrolyzed Formulas, and Timing of Introduction of Allergenic Complementary Foods.” American Academy of Pediatrics, American Academy of Pediatrics, 1 Apr. 2019, pediatrics.aappublications.org/content/143/4/e20190281
  8. Thomas, Dan W., et al. “Probiotics and Prebiotics in Pediatrics.” American Academy of Pediatrics, American Academy of Pediatrics, 1 Dec. 2010, pediatrics.aappublications.org/content/126/6/1217