Breast-Feeding the Microbiome
July 25, 2016 3:32 PM   Subscribe

Why do human mothers spend so much energy manufacturing complex sugars (the third most plentiful ingredient in human milk) that babies can't even digest? Why do these complicated chemicals pass through the stomach and small intestine unharmed? What if a large amount of breast milk isn't food for babies at all? What if it is food for microbes?
posted by AceRock (19 comments total) 29 users marked this as a favorite
 
The dairy industry has spent a fortune on extracting more and more milk from cows, but very little on understanding just what this white liquid is or how it works.
Call me crazy but I think farmers have their priorities straight here.
posted by rouftop at 3:36 PM on July 25, 2016 [10 favorites]


Wow, I can't wait to read that book (which comes out on my birthday, excellent). Thanks for the post!
posted by fiercecupcake at 3:54 PM on July 25, 2016


Two comments, as somebody who recently gave birth:

1. In contrast to what the article seems to believe, a fair number of preemies get breast milk. In my birth classes, they talked about pumping for preemies/techniques for more milk if your kid was still in the NICU. Two of my friends also has c-sections before 32 weeks, and they both pumped while their kids were in the NICU, which they indicated was a widespread practice.

2. Christ, more scientific-sounding but nevertheless vague stuff to shame people who can't breastfeed, or who elect not to, feel shitty about formula. Can anyone more knowledgeable talk about just what percentage of human milk HMO's make up? Or whether it's necessary to have that one kind of bacteria outcompete all other kinds of bacteria if the sealing out microbes/anti-inflammatory stuff is to happen? Are the article's summaries of those studies actually accurate?

I'd be less argh grar skeptical if I hadn't spent months being told, based on truly flimsy evidence, that I was increasing my child's chances of getting everything from cancer to being the shortest kid in class if he wasn't exclusively breastfed.
posted by joyceanmachine at 3:59 PM on July 25, 2016 [22 favorites]


more scientific-sounding but nevertheless vague stuff to shame people who can't breastfeed, or who elect not to, feel shitty about formula.

I for one hope the outcome is better formula formulations and not so much with the shaming.

I wonder if it's possible to synthesize these HMOs and how expensive they'd be to make? Maybe in a few years they'll have tanks of GMO yeast pumping the stuff out to add to formula.
posted by GuyZero at 4:18 PM on July 25, 2016 [5 favorites]



I wonder if it's possible to synthesize these HMOs and how expensive they'd be to make? Maybe in a few years they'll have tanks of GMO yeast pumping the stuff out to add to formula


Well there's an interaction I can't wait to see. GMO and breastfeeding in one argument! We do the separate issues so well!
posted by lalochezia at 5:03 PM on July 25, 2016 [9 favorites]


Part of what's important about research on breastmilk and breastfeeding in general is that it helps understand exactly what benefits (if any) there are to breast feeding, and how to replicate those for babies who aren't breast fed. The people I know who study lactation - especially Katie Hinde and Elizabeth Quinn - are explicitly not doing research on this to shame mothers who don't breast feed. They're interested in the range of human and nonhuman primate variation in nursing and what the means for infants and adults, and ways to leverage that information to improve human health. As with most of women's bodily functions, we don't understand everything going on with nursing and lactation, and I think that lack of knowledge is what allows the manipulation of the research that is out there.
posted by ChuraChura at 6:54 PM on July 25, 2016 [15 favorites]


Hi. I'm about to leave Salt Lake City, site of the 2016 annual meeting of the American Dairy Science Association. A tremendous amount is known about milk. Scientists around the world study it. There's plenty we don't yet know because nutritional physiology is hard, but it's not something we've been neglecting.
posted by wintermind at 7:11 PM on July 25, 2016 [17 favorites]


I don't think it's shaming mothers who don't breast feed, if we're discussing that formula is insufficiently engineered. We can build better formula, if we understand we need to.
posted by effugas at 9:14 PM on July 25, 2016 [11 favorites]


I don't think it's shaming mothers who don't breast feed, if we're discussing that formula is insufficiently engineered. We can build better formula, if we understand we need to.

Let me clarify my comment. I agree that neither article nor the book from which it is excerpted were written with the intent to shame people who use formula. I also believe that generally, researchers in the field don't intend for their work to be used to shame people who use formula.

Nevertheless, this article is totally, totally, totally going to used for that purpose, at least in the US. Sure, assholes gonna asshole, and God knows the La Leche League doesn't need any help being hardline. But the article's lack of detail and rigor, together with its breathlessness about the benefits/the way it leads the reader to believe that only breast milk will allow your kid to have the benefits of these magic bacteria -- I mean, yeah, it's a pop science story, but it's also straight out of the playbook of DON'T YOU WANT YOUR KID TO HAVE THE BEST START POSSIBLE???? DON'T YOU LOVE YOUR KID?????? toxicity used to shame American women about every single thing in connection with childbearing, including and particularly, choices regarding breastfeeding.

All of which it leads me to be argh grar skeptical of the article, especially in the context of the author seeming to assert that it's super-pioneering and unusual for preemies to get breast milk.
posted by joyceanmachine at 11:19 PM on July 25, 2016 [16 favorites]


Yeah, I'm confused by the end of the article. Vulnerable preemies do routinely get breast milk already, either pumped or donated. And it says people have studied probiotics before. So is the innovation giving only the one species of bacteria? Or pre-mixing the bacteria and the milk in some specific way?

Sometimes in science writing I feel like the author gets a little too starry-eyed over one person's research.
posted by gerstle at 5:11 AM on July 26, 2016 [1 favorite]


Let me actively concede, assholes gonna asshole, and the abuse of the facts you speak is not just possible, but likely.

The facts may in fact be what they are. There might be gaps (for example, we're already providing preemies with breast milk, and this is one reason that helps) but it's pretty solidly demonstrable that either these sugars are infant digestible, or they aren't. I don't want to see us reject science when it enables assholes.

We have to figure out better ways of managing assholes.
posted by effugas at 5:55 AM on July 26, 2016 [2 favorites]


For me, the fascinating thing about this is not breast milk shaming, but the idea that we are basically really smart lichens. We're not just humans that have been colonized by a complex mess of microorganisms. We're actually a deliberately balanced alliance of different species working collaboratively like, well not the Republican party obviously, but like a political party to balance the needs of all our component life forms and find a workable compromise. Its like Hobbes made literal. (not the tiger)

Also:
Call me crazy but I think farmers have their priorities straight here.

We work so hard to get this milk, bro. Do you ever stop and think about that? I mean why? Why do we even want it? What is it really, like, for man?

Clem, shut the fuck up and pass me that pulsator.
posted by Naberius at 6:18 AM on July 26, 2016 [6 favorites]


I think people who find today's emphasis on breast-milk excessive may be folks who weren't around when formula was advertised to mothers in India and elsewhere by Nestle and the like as being as good as or better than breast milk, causing massive detriment to public health. And India continues to have issues with the insidiousness of formula even today.

See this article for some global/historical context.
posted by splitpeasoup at 6:42 AM on July 26, 2016 [9 favorites]


I wonder if it's possible to synthesize these HMOs and how expensive they'd be to make?

Right now? Proooo~bably but very.
posted by maryr at 7:51 AM on July 26, 2016


Yeah, I'm confused by the end of the article. Vulnerable preemies do routinely get breast milk already, either pumped or donated.

Well, the disease the writer mentions (Necrotizing Enterocolitis, or NEC) occurs in about 10% of preemies (50% of whom die), and feeding preemies breast milk seems to cut the risk of death by half. Donated breast milk is expensive, and, as one might expect, the infant mortality rate from NEC is about 3 times as high for black preemies as it is for white preemies. In New York, at least, hospitals need a special license to offer donor milk and in California less than half of NICUs use donor milk. So maybe its not super-pioneering for everyone, but you know what they say about the future being unevenly distributed.
posted by AceRock at 10:04 AM on July 26, 2016 [7 favorites]


Human milk oligosaccharides? If the biochemical pathway can be determined, it probably wouldn't be very difficult to grow in a vat, or even synthesize chemically.

A very big part of why breast feeding is healthful is the presence of the maternal antibodies, especially IgAs. These are important not only in directly tagging microbes but by tagging these microbes maternal antibodies are thought to be able to 'inform' the baby's developing immune system.

Now, antibodies are determined partially by genetics (and recombination of available genetics) which is why you want high human leukocyte antigen (HLA, also known as major histocompatibility antigens, and even minor histocompatibility antigens are important) matching in transplantation.

Maternal antibodies share some similarity with the offspring's genetics (and HLA/MaLA/MiLA incompatibility between a potential mother and potential father has been suspected as a potential cause of some instances of infertility - two people are infertile with one another, but may be fertile with someone else - the developing fetus is rejected by the maternal immune system, which is also a hypothesis for some spontaneous miscarriages); I don't know if someone else's antibodies may be less effective in immune development.

Formula does not contain any antibodies.
posted by porpoise at 11:19 AM on July 26, 2016 [2 favorites]


Wait... human milk oligosaccharides pass through the stomach undigested and into the small intestine to promote the growth of (beneficial) bacteria?

That's what soluble dietary fiber, like inulin, does.

Does baby formula contain inulin? Why yes, yes it does (or should) and other oligosaccharides have also been explored.
posted by porpoise at 11:31 AM on July 26, 2016


I get the grar related to shaming issues for "failing" to breastfeed, but there is still a long way to go to make breastfeeding accessible and non-shameful for those who want and are able to do it and to make breast milk accessible to those who would benefit from it. It is not just a developing world issue. It's only in my mom's generation in the US that the pendulum started to swing away from shaming mothers who did breastfeed instead of using formula. When I was born, only about 25% of children born in the US were breastfed at all and less than 15% of children were breastfed past 2 months. Anecdotally, I know people in my generation who had kids in the last 10 years who were treated as GOOP-washed hipster eccentrics for breastfeeding and especially for trying to continue to do so while working, who endured regular undermining comments from concerned relatives. (Note that I did not put concerned in quotes because I think they were earnestly concerned due to years of anti-breastfeeding propaganda.)

Obviously, shaming those who cannot breastfeed (or choose not to for whatever reason) can't be part of the answer. Changing policies and culture regarding breastfeeding, such as workplace policies, seem like a good place to start. How can those policies be changed without acknowledging that breastfeeding is worth investing resources in? Since 2010 federal law protects a woman's right to have time and a place to pump but accommodations even at major employers are sometimes so terrible that women end up pumping in bathroom stalls or quitting altogether. Is it totally normal to store pumped milk in the fridge at work or is it pretty weird and a source of looks, sneers, and gross jokes? So there's a lot of propaganda and lip service but not so much actual support.

Likewise, the idea of providing donated breast milk for preemies is certainly out there, but is it accessible to those who need it? (Incidentally, I didn't see anything in the article that said preemies don't get breast milk; it did say doctors tried probiotics for preemies but found that strategy worked better when combined with breast milk.) If donated breast milk was not available in 80% of hospitals in California and at major medical centers like NYU only a year ago, it seems like it is probably not available to the majority of preemies today. There has to be some way to talk about increasing institutional and cultural support for breastfeeding without calling individual women's situations and choices into question, right?

In summary, it's fucking awesome that they are reverse-engineering breast milk at a much more sophisticated level than Nestle at al. did in the 20th century. It will probably, hopefully, ultimately help both the babies whose receive breast milk (or predominantly breast milk) and those who receive formula (or predominantly formula).
posted by nequalsone at 11:57 AM on July 26, 2016 [10 favorites]


Sorry, I was under the impression that smaller/sicker preemies always got donor milk. Totally wrong, apparently, forgive me.

I remain confused as to what the specific research is that's being described at the end of the article but I think it's probably just mixing the cultures with milk in advance of feeding rather than giving them as a separate dose.
posted by gerstle at 7:13 AM on July 27, 2016


« Older Say (American) Cheese!   |   The Ghostess with the Mostest Newer »


This thread has been archived and is closed to new comments