Janet's post on The New York Times breast-feeding article reminded me that I had a related post in the hopper that I had drafted at the old blog back in May. I wrote it following PZ Myers' beautiful and scholarly repost from classic Pharyngula on the human breast milk and the origin of the word galaxy. As is all too common with me, my comments there were longer than most folks' blog posts, so I'll reproduce them here:
While reviewing the literature when my wife was breastfeeding, I was amazed to learn of the other beneficial compounds present in breast milk beyond the nutrients [Prof Myers] listed [t]here. Breast milk contains TGF-beta1 and 2, the latter of which has been associated, but not yet causally, with decreased incidence of atopic dermatitis and other atopic disorders in breast-fed infants. Interestingly, (and I have yet to understand the mechanism) ingestion of probiotic supplements by nursing Moms increased the TGF-beta2 concentration of their breast milk more than two-fold.
Mind you, I would be extremely cautious about nursing Moms taking any kind of supplements beyond multivitamins, but this was done under the auspices of a clinical trial and is simply just like eating a good helping of yogurt. I'm also amazed that the TGF-beta2 would have oral bioavailability to permit systemic absorption and distribution, but all bets are off in the neonate.
Finally, folks at the University of Arizona have even found that the breast milk of Moms with extremely premature infants have elevated levels of EGF and TGF-alpha and these could certainly have enough local bioavailability to prevent the gastrointestinal disorders associated with extreme preterm births. Unfortunately, these babies are off in the [neonatal] ICU away from their lactating mothers. Of course, they wouldn't survive without intensive care, but there is incredible biological beauty in the attempt by the mother's body to provide greater concentrations of helpful peptides to their premature offspring.
- Log in to post comments
Unfortunately, these babies are off in the [neonatal] ICU away from their lactating mothers
Huh? A friend of mine has a premie in the NICU right now; he (the baby) is getting momma's milk by way of expression and cold storage. I wouldn't expect that to affect EGF or TFGalpha much.
truly amazing i agree. i guess of all the functions necessary for survival, providing nourishment to offspring is the most critical, and therefore the most honed by evolution into magical stuff. great post.
Bill, a very good point you make - I hadn't been aware that preemies in the NICU received expressed breast milk. That's awesome.
Dr Charles, thanks so much for coming over. Human physiology is remarkable and it amazes me how much wisdom is in the biology when we start turning over the stones. As I said at your place, it's an honor to be writing alongside you.
It's a shame that there isn't a mechanism for mothers of premature infants to produce breast milk of higher caloric density. We will always have to fortify breastmilk to give it more calories, something that preemies need more of than term babies, as well as a few other things like extra iron and some vitamins.
Are you aware of any studies trying to find a correlation between being breastfed as an infant and having lower C-Reactive Protein levels later in life?
Doc Bartram: good to know one of the limitations to using breastmilk in the NICU.
Coturnix: there are some rather surprising prospective and epidemiological studies that are highly suggestive that breastfeeding as an infant reduces one's cardiovascular risk factors in adolescence through adulthood.