Human milk is essential for a baby’s nutrition, digestion, metabolism, growth, and development, including brain development. That’s why the World Health Organization recommends that infants be breastfed exclusively for the first six months of life.^[1] After six months, or with the emergence of the baby’s first tooth, infants may be introduced to solid foods and water while continuing breastfeeding. No artificial milk is necessary.

What Are the Main Benefits of Breastfeeding?

Breastfeeding protects babies against infection and inflammation. This is because human milk transfers antibodies critical to bronchial and intestinal immunity. This immunity can last well into adulthood. Additionally, innate immune factors in human milk composition prevent the binding of some pathogens (disease-causing bacteria and viruses) and offer protection against infection.^[2] Human milk composition also promotes favorable gut microorganism colonization and aids in the development and function of the intestinal barrier, guarding against gut permeability. According to the leaky gut hypothesis, breastfeeding should effectively offer protection against some auto-immune diseases.

And these benefits are only scratching the surface. Scientists are discovering new reasons to encourage breastfeeding all the time. Lead researcher at the University of Illinois, Sharon Donavon, describes how breastmilk positively affects the expression of genes relevant to intestinal development and immunological function: “Genes are really sensitive to nutrition and we now have genes that may explain many of the clinical observations of how breast-fed and formula-fed infants differ.”^[3]

Breastfeeding Versus Formula

Studies investigating breast milk composition since the 1960s have revealed an increasing number of components, and new components continue to be identified. In contrast, infant formula is standardized within a very narrow range of composition.^[4]

In addition to the complexity of its composition, what sets breast milk apart is that it is dynamic. It changes within a feeding, whether at night or during the day, and it varies over the stages of lactation. These stages begin with colostrum in the first few days post-birth and develop over the next few weeks; by six weeks, it is considered fully mature, but subtle changes continue as the baby grows. Its composition also varies between individuals and between population groups.

Scientists simply cannot reproduce human breast milk in a way that reflects this dynamism and complexity. While the decision to feed a baby is the parent’s choice, the case for breastfeeding could not be stronger, and any mother would be well-advised to give breastfeeding an attempt before considering other options.

Two reviews published in 2007 and 2009 refer to the evidence of the effects of breastfeeding compared to formula feeding and collectively indicate that breastfeeding reduced risks of infant ear infection, gastroenteritis, severe lower respiratory tract infections and pneumonia, eczema, asthma and food allergies, childhood obesity and the metabolic disease, diabetes (type 1 and 2), leukemia, and infant mortality including sudden infant death syndrome (crib death). Premature babies fed on formula risk necrotizing enterocolitis (intestinal tissue death).

Of course, there are some situations where it might be necessary to complement breastfeeding with formula, and there is no blame for any mother unable to breastfeed. The key takeaway is that formula feeding should be the last resort. If you would like to try the practice of wet nursing or expressing milk for others, there are some recommended hygienic procedural guidelines.^[5]

Overcoming Big Business and Cultural Norms

Many people in our society have become desensitized to the value of human breast milk. While the invention of formula is helpful for those unable to breastfeed, it is often presented as an alternative. It allows women to more easily return to work a mere six weeks after giving birth. This might sound more convenient and economically productive, but it is not optimally healthy. Most often, it means women cannot breastfeed for a full six months.

Overcoming the big business of formula and the cultural norms that say it is okay to not breastfeed for a minimum of six months is important not only for the health of the baby but also for the mother. Mothers who do not breastfeed or stop too early are associated with a higher risk of retained gestational weight gain (failure to lose weight gained in pregnancy), type 2 diabetes and metabolic syndrome, breast and ovarian cancer, cardiovascular disease and heart attack.^[6][7]

What About Cow’s Milk?

Mammalian milks are indeed a true wonder of nature and differ tremendously between mammalian species. That’s why using other species’ milk to supplement or replace your own is not a good idea. Introducing cow’s milk to a child’s diet is associated with type 1 diabetes.

It’s also important that lactating mothers avoid drinking cow’s milk; cow’s milk proteins pass through breast milk, which causes colic in a baby.^[8] More shocking are “the opiate-like effects of the casomorphin in cow’s milk (passed through breastmilk) [which] may have a depressive effect on the respiratory center of infants, and lead to milk apnea, in which babies temporarily stop breathing and are placed at risk for sudden infant death syndrome.”^[9] This has been proven in at least one related case.

The bottom line is that breastfeeding, as intended by nature, should be the normative way to feed an infant. Cow’s milk should be avoided. And while formula certainly has its uses, it should only be used as needed.

“The scientists’ religious feeling takes the form of a rapturous amazement at the harmony of natural law, which reveals an intelligence of such superiority that, compared with it, all the systematic thinking and acting of human beings is an utterly insignificant reflection.”

References

1. World Health Organization (WHO). Infant and young child feeding. June 9, 2021. http://www.who.int/mediacentre/factsheets/fs342/en/
2. Peterson JA, Patton S, Hamosh M. Glycoproteins of the human milk fat globule in the protection of the breast-fed infant against infections. Biol Neonate. 1998;74:143–162.
3. Pompa RN. Breast milk does DNA good. LiveScience. May 22, 2010. http://www.livescience.com/6498-breast-milk-dna-good.html
4. Olivia Ballard, JD, PhD; Ardythe L. Morrow, PhD, MSc. Human Milk Composition: Nutrients and Bioactive Factors. HHS Public Access PMC3586783. Published in final edited form as: Pediatr Clin North Am. 2013 Feb; 60(1): 49–74.
5. University of Rochester Medical Center (URMC): Health Encyclopedia. Breastmilk: pumping, collecting, storing. Accessed August 24, 2023. https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=90&contentid=P02385
6. Alison Stuebe, MD, MSc. The Risks of Not Breastfeeding for Mothers and Infants. Rev Obstet Gynecol. PMC2812877. 2009.
7. Stanley Ip, Mei Chung, Gowin Raman, Priscilla Chew, Nombulelo Magula, Deidre DeVine, Thomas Trikalinos and Joseph Lau. Breastfeeding and Maternal and Infant Health Outcomes in Developed Countries. PCMC4781366. 2007
8. Irene Jakobsson, Tor Linberg. Cow’s Milk as a Cause Of Infantile Colic In Breast-fed Infants. The Lancet Volume 312, Issue 8087, 26th August 1978 (http://nutritionfacts.org/video/treating-infant-colic-by-changing-moms-diet/ ; http://www.sciencedirect.com/science/article/pii/S0140673678914411)
9. Wasilewska, Jolanta; Kaczmarski, Maciej; Kostyra, Elzbieta; Iwan, Malgorzata. Cow’s-milk–induced Infant Apnoea With Increased Serum Content of Bovine β-Casomorphin-5. Journal of Pediatric Gastroenterology & Nutrition: June 2011 (http://nutritionfacts.org/video/cows-milk-induced-infant-apnea/?utm_content=buffer833e0&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer ; http://journals.lww.com/jpgn/Fulltext/2011/06000/Cow_s_milk_induced_Infant_Apnoea_With_Increased.21.aspx)