Breastfeeding

The magic of breast milk

 A while back I did a deep dive into the benefits of human milk and breastfeeding, and what makes it so unique compared to the animal milk we drink as adults

This is a compilation of some of the interesting things I've learned

First off, breast milk contains a type of soluble fiber known as human milk oligiosaccharides (HMOs) HMOs are the preferred food of Bifidobaceteria, a genus of beneficial organisms in the gut, breast milk contains baceteria as well and is the first probiotic infants consume

Oddly the macronutrient ratio of breast milk (specifically lactose/lipids) shifts throughout each feeding and even over time as the infant grows I don't know whether this happens to fulfill changing energy requirements or if it depends on the mother's diet, but it is interesting

Breast milk produced at night actually contains a significant dose of melatonin, studies show that because of this breast-fed babies are more likely to sleep through the night This may be affected negatively if the mother's melatonin production is impaired by artificial light

Beyond melatonin, breast milk also contains trace amounts of morphine, and possibly other neurotransmitters as well Theses signaling molecules seem to synchronize the mother and baby's circadian rhythm and calm the infant

This connection is known as the mother-infant dyad Different milk is produced for girls vs. boys, premature vs. on-time birth, etc, this connection plays an important role in early infant development

Through the mother-infant dyad breast milk also ties together the mother and infant's immune system Breast milk contains macrophages which clear out pathogens and damaged cell fragments, this helps build the foundation for what will become the infant's adaptive immune system

Breast milk also contains a compound called lactoferrin, a protein similar to transferrin that binds up excess unbound iron in the body During pregnancy the mother give the infant plenty of copper through the placenta, then breast milk maintains the balance between copper/iron

Interestingly, lactoferrin also has potent antiviral properties, so it may also work as an immune system support to protect the infant against viral infection in early childhood

Children need more PUFA than adults to support their high rate of neurogenesis, especially omega-3 fats They require about 10% of caloric intake in the form of these unsaturated fats (we see breast milk contains about this amount)

As for the benefits of breastfeeding: Children that are breast-fed show better cognitive function and socialization, which is thought to stem from increased neurogenesis and oxytocin release

https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC6096620/

Mother's that breast feed for longer may have a reduced risk of developing type 2 diabetes after the fact

https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC4052010/

This study showed a similar reduction in type 2 diabetes risk, but also found a reduction in breast cancer risk with long term breastfeeding as well

https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC4670483/

Breastfeeding is associated with significant increases in oxytocin and reduction in cortisol in mothers

https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC7406087/

Children breast-fed for more than 1 month show several points higher IQ scores at 5 years of age

https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC7406087/

Lastly, in many parts of the world (perhaps everywhere), breastfeeding is a significant factor in reducing infant mortality rate and preventing malnutrition

https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC37315/