Baby formula is our best attempt at a breast milk substitute… but falls short
Jump to the “I’ve been wearing the same pajamas for the last 48 hours… can you just summarize this for me?” summary, here.
Breast milk is pretty darn cool
Breast milk is just the best! It is full of the perfect amounts and types of fat, protein, and carbohydrates for a growing baby. Breast milk also contains all kinds of other non-nutrient compounds that protect baby and help him develop. These include hormones, antibodies, probiotics (healthy good bacteria), and prebiotics (food for those healthy bacteria), just to name a few! There is still so much we don’t understand about exactly how breast milk does such an amazing job protecting baby. In fact, researchers (such as myself!) have built entire careers studying human breast milk.
But this series is about formula. I could go on-and-on about breast milk but will cut myself off. If you want to read a great summary of the benefits of breast milk, the American Academy of Pediatrics has a great article (1). While breast milk is the optimal choice, many parents can’t, or choose not to, feed their infants formula. How you nourish your baby has no impact on your value as a parent. Once parents make the choice to use baby formula, they should be able to feel confident picking out a formula that fits their family’s needs.
The point I want to make here is that baby formula is our best attempt at creating a human breast milk substitute… which is kind of an impossible task. Here’s why:
Breast milk is not simple
The problem is – there is incredible variation in what we find in breast milk! For example, the amount of fat in human breast milk can range anywhere from 2 to 9 g/100mL between women (2). Similarly, the amount of other vitamins, minerals, and calories in breast milk dramatically varies between women. Much of this variation can be explained by differences in maternal characteristics and behavior, but some cannot.
For example, the amount of iron in breast milk does not really depend on maternal diet. However, the content of some essential fatty acids (like, docosohexanoic acid, or DHA, which is the fatty acid in fish oil that everyone goes crazy over) can differ up to ten fold depending on what country Mom is from and what type of diet she eats (2).
So how do we know what to put in formula? Well, we often shoot for the average value of what is found in breast milk, or estimate what a baby needs based on what is needed to meet the growth demands of an average infant. In short, we guess. It is an educated guess, yes, but still a guess.
There are plenty of non-nutrient components in breast milk that are so independent to Mom and Baby that we haven’t even attempted to put them in formula yet. The obvious example is antibodies (parts of our immune system that fight and kill germs). Mothers pass antibodies to their babies through their breast milk. This is incredible because it provides baby (who isn’t great at making his own antibodies yet) with the antibodies needed to fight off viruses, bacteria, and other germs that live in the infant’s individual environment. How amazing! But how difficult to mimic in formula!
Other characteristics of milk are often “individualized” to individual babies. For example, the milk produced by mothers who deliver prematurely has more protein, calories, calcium and phosphorus than milk of mothers who deliver at term (3). This helps meet these little babies’ higher calorie and protein needs. All of this variation combined makes it difficult for researchers and doctors to create a perfect baby formula because the optimal diet for one infant may actually be quite different from that of another infant.
Breast milk is not consistent
There’s another major challenge facing our attempt to create the “perfect” breast milk substitute. This is: breast milk is ever-changing! The composition of breast milk changes across a feed, throughout the day, over time as the baby ages, and with special circumstances, like an illness. This is clearly very hard to mimic! Formula fed babies (obviously) only get one food that is the same in composition and doesn’t change over time.
All these points combined illustrates that there are several characteristics of breast milk that we will never be able to re-create in formula (at least with our current food science technology). Since we’re starting off at this disadvantage, it is critical that we perfect the things that we can control in baby formula. Research is continually ongoing to improve the composition of baby formulas. The next few articles in this series are designed to educate parents about what is in formula, and why it’s there, so they know how to make a choice based on your individual baby’s characteristics. The more parents execute educated decisions in the market, the more demand we will generate for further improvements in infant formula. That’s everyone’s goal!
Disclaimer: Focus on healthy term babies:
From here on out, I will be focusing on formula for generally healthy infants who were delivered at term (at least 357 weeks). Premature infants and infants with serious health conditions often have special nutritional needs that necessitate specific interventions. We’re focusing on healthy term babies without special medical needs
In the next article, I’ll explain exactly how much/little the FDA regulates infant formula and why your doctor may not know all the latest infant formula research.
- Baby formula is the food industry’s best attempt at creating a human breast milk substitute.
- Regarding the amount of individual nutrients in formula, we often shoot for the average value of what is found in breast milk, or estimate what a baby needs based on what is needed to meet growth demands. In short, we guess.
- Certain components of breast milk are individual to Mom and Baby and thus cannot be duplicated.
- Breast milk is constantly changing, but we cannot mimic this in baby formula.
- In short, when creating infant formulas, we are forced to guess and produce a one-size-fits-all product.
- Meek J, Noble L, AAP Section on Breastfeeding. Policy Statement: Breastfeeding and the use of human milk. Pediatrics 2022; 150(1):e2022057988.
- Stam J, Sauer PJ, Boehm G. Can we define an infant’s need from the composition of human milk? Am J Clin Nutr 2013;98(2):521S-8S. doi: 10.3945/ajcn.112.044370.
- Lawrence RAL, R. M. Breastfeeding – A Guide for the Medical Professional. 9 ed: Elsevier Mosby, 2021.