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Cow's milk versus human milk

  1. Aug 9, 2016 #1
    I am writing a blog post about dairy and it suddenly occurred to me to wonder at the value of human breastmilk. That is, if cow's milk is so good for us, yet is from a different species, how would we get on if we drank human milk? A search of the web turned up nothing much at all. A slew of articles mid 2015 cast doubt over the idea, but on reading these, all I really learned is that human milk contains less protein. Hardly surprising. And that tells me nothing about the relative quality and quantity of protein in human milk vs cow's milk. Nor does it tell me much about the relative nutrient profiles of each. Current dietary guidelines suggest quite moderate consumption of low-fat forms of milk, cheese and yoghurt in order to maximise benefit and minimise risk. But could similar nutritional value be derived from human milk without the risk factors (assuming identical production quality), presumably through greater daily consumption. This is just a hypothetical as opposed to any serious suggestion, mind you. I'm not aiming to drink human milk anytime soon...

    Note: I am referring to adult consumption, rather than by infants.
     
    Last edited: Aug 9, 2016
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  3. Aug 9, 2016 #2

    Grinkle

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    graph from the below web site.

    http://www.viva.org.uk/white-lies/comparison-between-human-milk-and-cows-milk


    upload_2016-8-9_8-14-45.png

    At least looking at this simple graph, it seems a straightforward comparison.

    Do you want carbs or protein as an adult?

    Personally, I need to deliberately eat more protein than I am inclined to and I need to eat fewer carbs than I am inclined to if I want to feel fit (subjectively).
     
  4. Aug 9, 2016 #3

    jim mcnamara

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    I'd go to page 1 - and start from there. Note: Raw milk from the cow has different lipid profiles and taste from pasteurized homogenized milk.
    Some lipid-related goodies are altered in pasteurization. Thermized milk is another confusion. I'm not advocating raw milk, just trying to 'clear the field' a bit.
    So let's just go with pasteurized milk. Note that milk often has added Vitamin D, sometimes other nutrienmts. Pasteurization and nutrient additions make comparisons with human milk more 'interesting'.

    The USDA nutrient database is considered the standard reference for human food nutrient content in the US, Britain has a similar reference:
    (Click the full report button at the top to see stats and detailed lists of nutrients test for (expand subsections also) )
    Skim milk: https://ndb.nal.usda.gov/ndb/foods/show/78
    Whole (3.25% fat) milk: https://ndb.nal.usda.gov/ndb/foods/show/70?manu=&fgcd=

    Human milk note colostrum is different:
    http://www.ncbi.nlm.nih.gov/pubmed/392766
    Human milk banking
    Also consider: https://www.hmbana.org/

    My take: widespread consumption of human milk by adults is not feasible, IMO likely not ethical either. There is also the possibility of pathogens, just like in sheep, cow, goat, and camel milk. Most widely used milk sources for human consumption.

    You may also want to widen your 'milk scope' to include other species' production of milk.
     
  5. Aug 9, 2016 #4
    Thanks for these, I will have a look. As I said, it was just idle curiosity that aroused my interest rather than a serious suggestion. I was more curious about a direct comparison. Cow's milk is often sold with additives to increase it's nutrient value, so I wondered at the actual one to one comparison. That is, raw human milk versus raw cow's milk, assuming identical production values. And yes, it then occurred to me that as other mammals produce milk, one could wonder at the comparison with milks more generally.

    I suppose that given there is no biological imperative to drink any milk at all as adults, our adoption of that seems to be a cultural adaptation. Were we a species without hands we'd never have done it. So I assume that we could find another mammal whose milk offers similar benefits (though how to produce it in large quantities might be another matter - can't see large-scale farming of blue whale milk for example!!).

    Unless there is something unique about cow's milk?

    Update: Thanks for the link to the Viva site, that has answered my question sufficiently. I will assume that it is evidence based given the various cites, even though it clearly has a particular point of view.
     
    Last edited: Aug 9, 2016
  6. Aug 9, 2016 #5

    Evo

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    Here is an interesting article.

    continued...

    http://www.slate.com/articles/life/..._of_camels_buffalo_pigs_sheep_and_goats_.html
     
  7. Aug 9, 2016 #6
    Very interesting, thanks Evo. Also a good point about the ease of domestication of the aurochs and also the mechanical usefulness of large teats.

    On a side issue, I found this comment on another thread here:
    https://www.physicsforums.com/threads/when-did-adult-humans-start-drinking-milk.522602/

    "Being able to drink milk after young childhood is a phenomenon called lactase persistence and has evolved multiple times in human history. Lactase persistence is caused by a mutation in the LCT (lactase) gene....

    ...the mutation (is dated) at somewhere between 7,400 and 12,000 years old. This is interesting because it coincides with the adoption of cattle farming in Europe, additionally analysis of ancient DNA shows that the allele is either not present or is at very low frequency before this time...

    It is difficult to say how lactase persistence is an advantageous allele. The calcium assimilation hypothesis that posits that in populations with insufficient sunlight lactase persistence makes up for vitamin D loss though this theory does not explain how African and Arab populations evolved LP. The nutritional hypothesis posits that the nutritional benefit gained from lactose is such an advantage on its own it is strongly selected for though there is no strong evidence of this.

    Whilst the exact reason as to why LP is an advantage is not known it is safe to say that it is clearly an advantage to have been selected for at multiple times in history..."


    My grasp of evolutionary biology is flimsy at best, however an immediate thought is that perhaps the mutation is not directly advantageous as such. Rather, it confers survival protections for a cultural practice. Evolution responds to natural pressures, and so we assume advantageous benefits to accrue from those changes that become fixed in a population. But human cultural practices are not natural in that sense.

    Perhaps cheese and yoghurt consumption arose through cultural preferences and the LP adaptation confers survivability AGAINST that practice?
     
  8. Aug 9, 2016 #7

    Grinkle

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    Imo, a much simpler explanation is that in a culture where cows milk is a relatively available nutrient, infants that can tolerate it will tend to survive more than infants who cannot.
     
  9. Aug 9, 2016 #8
    Maybe. I have read though that originally consumption of milk was in the form of cheeses and yoghurts, rather than milk per se. It seems a short step from there to trying milk as itself, but then Lactose intolerance rears its head. I have also read that raw cow's milk is NOT a useful food for human infants, and in any case infants ARE lactose tolerant. We lose the tolerance after weaning, so LP is an adaptation for adult consumption.
     
  10. Aug 9, 2016 #9

    Grinkle

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    As long as tolerance matters before puberty, then I think the reasoning holds. If one only loses tolerance post-puberty, then the argument needs to be that better fed parents help children survive, and to me this is a less defensible argument.
     
  11. Aug 9, 2016 #10

    jim mcnamara

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    @Grinkle
    Sub-polar, semi-arid, and montane grasslands support grazing species. Few other crops do grow, so if you practice animal husbandry you survive. Kill a cow you eat for 2 weeks. Milk a cow you eat for many months. This is the reason most Northern Europeans are lactose tolerant as adults ( adults have to live long enough to raise a kid to puberty, not simply have a kid and then die.) is simple: grasslands and grazing animals.

    See 'The Social Conquest of Earth' E O Wilson 2012
     
  12. Aug 11, 2016 #11

    Fervent Freyja

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    There's already a great demand for human breast-milk. Hospitals pay up to $4 an ounce, which currently makes it around $512 a gallon, versus the $0.89 per gallon of cows milk in my area. Human breast milk is higher in carbs (tastes sweeter), has less protein, but cows milk has more of a protein that is more difficult to digest for humans. The fat content is more equivalent, but human milk has more unsaturated fat and has omega-6 and 3's that cow milk doesn't. Cows milk is higher vitamins and minerals like sodium, calcium, potassium, magnesium, vitamin b's and iodine, not good for infant kidneys, but a much better fit for adults to consume! I don't see where adults would benefit from the antibodies, natural antibiotics, antitoxins, good bacteria, neurotransmitters, hormones and loads of other goodies in human breast milk.

    Adults are equipped to deal with all that for themselves, and that actually not be very good for adults at all! It is meant to be a tailored nutrient source for an infant, breast milk composition changes throughout the day. Even depending upon weather, for example, when a mother is experiencing a very hot day, the body will produce milk for the infant that has less protein, more water, carbs, and electrolytes! If the mother is present with the infant all day, then the infant will gain protection from pathogens that the mother encounters (though it doesn't work so well if the milk is pumped and the infant is exposed to pathogens that the mother has not been). There are many amazing aspects of human breast milk, much is left to learn! Unfortunately, this is one of those touchy topics, so the benefits of it aren't being advertised as much as one would expect. In fact, I encountered a lot of negativity about my own personal choice to breast feed!!! A few family members were against me doing it (they didn't). There is also much online attempting to shame women for it: New Study: Breastfeeding Might Be Hazardous To Your Baby's Health! I wouldn't condemn another woman for not breastfeeding, I know myself that it was the most challenging part of being a mother for me! The time, attention, and energy I put into nursing had been far greater than anything else I did for my daughter throughout the day, especially at first! It did get easier over time, I read a lot and learned to multi-task. I hadn't been accustomed to anything needing my attention so much, it was certainly a shocking experience at first! I don't condemn other women for using formula, I don't know their situation, and I know how lucky I've been to be able to stay at home and take care of her. Not all have that opportunity.

    There's broad agreement in the milk-banking industry of a shortage of human milk available for hospitals and NICUs.

    The nonprofit Human Milk Banking Association of North America estimates that there are 4,000 mothers using its banks across the country and that it would take 60,000 to meet the demand for milk in hospitals nationwide.


    I'm not sure what the maximum ounces are that women can pump in one day. I mainly nursed (you can't really measure it there), but did pump extra for excursions/bottles. After my daughter was 6 months I suppose she was getting 25-35 ounces a day from nursing, and usually was still able to pump 8-12 ounces to freeze. It takes around 20 calories to produce one ounce of human breast milk (worth 20 calories); whereas, an ounce of whole cows milk is just 12 calories. There is a lot of time involved in nursing and pumping, which you can not do all day long, there are intervals (hers was 2.5-4 hours) and maximum pumping times; around 30 minutes seemed to be the very most that I could pump (from both breasts). A cow can produce 6 gallons a day, and the most I probably produced in a day couldn't have been more than 60 ounces (a half gallon)! I recall getting around 3-4 ounces and pumping 15/20 minutes. A woman could be making $48/hour if she produces 3 ounces every 15 minutes! But, like I said there are many limitations, that would only be in theory. Anyway, where do you reckon you'd get the women willing to pump for money when not all women can't breastfeed their infants as it is (they are having to work usually)? Pulling that many women out of the workforce to pump would cause a national disaster in order to match the entire child/adult consumption of cows milk in the US!

    Even so, in order to mass produce human breast milk, steroids and other hormones would have to be taken, which isn't healthy for cows, much less humans. It would also have to be pasteurized and the milk would have to be screened for toxins/pollutants like breast milk banks already do. I do see there being a great benefit to mothers and children in selling breast milk, I can see pumping an extra 20 ounces a day bringing in $2400 a month (if the prices remained steady and supply consistent), which would allow them to be together. That probably wouldn't be enough to totally support costs of living nowadays, but if the father were already working then it might. But, I don't see adults being able to afford $512 a gallon, or it being a health benefit to adults any more than cows milk. It could actually be bad for adults to consume, there isn't much research on the topic.
     
  13. Aug 11, 2016 #12
    A very comprehensive post that covers the topic from a different angle, thanks for your thoughts Freyja. I should again emphasise that I was really just thinking hypothetically rather than making any kind of suggestion.

    I have been thinking about dairy as an industry following my exposure to a variety of arguments against it and it's caused me to research a number of the claims being made. In the course of that it occurred to me to wonder at the comparable risk/benefit ratio for human milk when compared to cow's milk. I didn't mean that in any realistic sense as there are all sorts of other factors at play. But dairy is always being promoted for its health benefits, yet it is actually a naturally tailored food for the infants of another species. So it occurred to me to wonder at how human milk might fare if we were to consider it on a level playing field as it were.

    In other words, if we hypothetically had a world in which it were possible to source human milk in vast quantities, all produced safely and in the same way as cow's milk, would it produce a healthful food for adults? If not, then why would the milk for another species be better? If yes, would it be more suitable for adults than cow's milk? Or as noted above, any other mammal's milk?

    It's obvious why animals do not consume milk into adulthood, but that's from an evolutionary perspective. Considered in that light, it may well be that human breast milk is hazardous to *some* babies, even if not all. After all, nature doesn't care if some babies don't make it, only if enough do to make the species viable over the long run. It's us that add into the mix the idea that every one of us is vitally important and should live forever.
     
  14. Aug 12, 2016 #13

    Grinkle

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    Considering first world uses, where folks eat what they want as opposed to what is available, this may not really be an either/or discussion.

    If we could vat-grow human breast milk somehow, I expect we would, and I expect there would be a market for it. Since it is so much sweeter than cow's milk, it might not end up being marketed as an alternative to cow's milk. I could be a different food product with a different niche than cow's milk, and not displace current uses for cow's milk.
     
  15. Aug 12, 2016 #14
    My brother's girlfriend of the time became pregnant and developed a condition, (can't remember the technical term), where she was overproducing milk quite some time before the baby was born.
    The condition wasn't dangerous, but was uncomfortable, the excess milk could be removed either by a device, or she could do it manually.
    My brother (in his 30s), decided to try the extracted milk, just as a curiosity kind of thing.
    Apparently it did no harm, and no noticeable benefit to it either, but he says it tasted very sweet, so presumably human milk has a higher sugar content than cows, but is not very different.
     
    Last edited: Aug 12, 2016
  16. Aug 14, 2016 #15

    Fervent Freyja

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    Leakage months prior to labor is common. Trying to remove the milk is what probably increased the supply even further! The amount of milk a woman has ready for one sitting usually depends on the prior demands. You don't use it, you lose it! I've heard of some women trying to start contractions by stimulating their nipples. I kept my supply for many months after I'd weaned my daughter, she was over 2 years old at the time, I think. Probably more sad to let it go than she had been!

    Dare I say, most men are curious to try their baby mamas' breast milk... :wink:
     
  17. Sep 10, 2016 #16

    Evo

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    Closed pending moderation.
     
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