Results 1 to 8 of 8

Thread: Can we trust B12 supplements?

  1. #1

    Join Date
    Jun 2012
    Location
    São Paulo
    Posts
    14

    Default Can we trust B12 supplements?

    Does anyone know if there are studies showing the statistics of Vitamin B deficiency in vegans THAT DO TAKE SUPPLEMENTS (pills or fortified food)?
    I searched in Google and in this Forum, but all the studies I find were done with vegans that weren't taking supplements (it's possible that I have overlooked, though)

    This information is necessary because some people say that the B12 supplements may as well not be bioavailable/active for humans and that only the "natural" vitamin B12 - the one you get from meat - can be effectively used by the body.

    Thank you

  2. #2
    Ex-admin Korn's Avatar
    Join Date
    Apr 2004
    Location
    Europe
    Posts
    4,830

    Default Re: Can we trust B12 supplements?

    "....only the "natural" vitamin B12 - the one you get from meat - can be effectively used by the body."
    Hi Edu,
    I've never heard anyone claim such a thing. Can you list any sources for that viewpoint?
    We discussed a similar topic a few days ago, here...
    B12 and B12 analogues in multivitamins, animal foods and spirulina

    ...but this was about multivitamins containing copper, iron, vit. A and biotin only.

    In terms of bioavailable vs. active: remember that inactive B12 analogues can found in animal products* as well, so although inactive B12 analogues may be found in both in animal products, fortified food and multivitamins, this doesn't mean that regular B12 supplements won't work.

    The same is true for non-animal products: the existence of inactive B12 analogues doesn't necessarily mean that none of the active B12 will be absorbed. A lot of factors are important here – e.g. the ratio between inactive and active B12.

    *ETA:
    As the intrinsic factor-mediated intestinal absorption system is estimated to be saturated at about 1.5–2.0 µg per meal under physiologic conditions, vitamin B12 bioavailability significantly decreases with increasing intake of vitamin B12 per meal. The bioavailability of vitamin B12 in healthy humans from fish meat, sheep meat, and chicken meat averaged 42%, 56%–89%, and 61%–66%, respectively. Vitamin B12 in eggs seems to be poorly absorbed (< 9%) relative to other animal food products.
    I will not eat anything that walks, swims, flies, runs, skips, hops or crawls.

  3. #3

    Join Date
    Jun 2012
    Location
    São Paulo
    Posts
    14

    Default Re: Can we trust B12 supplements?

    This point was expressed in an oral discussion. The person didn't have any ground to say that, but some people do believe that vitamins added to your diet through artificial methods and, especially, by taking pills, don't help so much. That's why some people say that eating vitamin compounds like Centrum® is just a waste of money.

    Anyway, it would be a very powerful argument if we could say that:
    Not only vegans can have their share of Vit B12, but also going vegan usually solves the problem of Vit B12 deficiency, since they become concerned about the issue and start taking supplements or eating fortified food, which is something that every person should do regardless of their diet.

    "Nearly two out of five people of all ages tested by Dr. Katherine L. Tucker had B12 levels below normal ... Although vitamin B12 is obtained from meat, it's not well absorbed through digestion, so supplementation is the best way to prevent B12 deficiency" - American Journal of Clinical Nutrition 2001;71:514-522

    It would be just a killer to have the next number: "among vegans who eat supplements or eat fortified foods, less than 1% presented low levels of Vit B12"


  4. #4
    Ex-admin Korn's Avatar
    Join Date
    Apr 2004
    Location
    Europe
    Posts
    4,830

    Default Re: Can we trust B12 supplements?

    Quote Edu View Post
    The person didn't have any ground to say that, but some people do believe that vitamins added to your diet through artificial methods and, especially, by taking pills, don't help so much.
    Well, people "believe" all kinds of things.

    And regarding natural vs artificial methods - and thats a totally different topic, discussed in several other threads: since humans, from nature's side, aren't equipped with the speed, claws, teeth etc it takes to catch and kill eg. sheep or cows, a meat based diet is a cultural/man-made, and not a natural thing. If it's so 'natural' for mammals to drink milk from another species, and keep doing it for life, why are no other mammals doing that?

    People who come up with such claims always demonstrate that they aren't really worried about natural - not on that level. Both 'cultural' and 'natural' is fine with them; they sleep in houses, wear clothes, use fermented products (beer, yogurt, kefir, black tea) and so on.

    Also - they all seem to 'know' that B12 comes from animals (B12 comes from bacteria), and won't even look at reports insisting that humans can avid B12 deficiency by using non-animal sources. We have some of them in the B12 in plants?"-section. Here is one: Serum vitamin B12 levels in young vegans who eat brown rice. NB: I'm not saying that eg. all Nori can be used, for all people, to stay away from B12 deficiencies; I don't even have an opinion about that - but instead refer to (often conflicting) studies about others' findings.

    Anyway, it would be a very powerful argument if we could say that:
    Not only vegans can have their share of Vit B12, but also going vegan usually solves the problem of Vit B12 deficiency, since they become concerned about the issue and start taking supplements or eating fortified food, which is something that every person should do regardless of their diet.

    "Nearly two out of five people of all ages tested by Dr. Katherine L. Tucker had B12 levels below normal ... Although vitamin B12 is obtained from meat, it's not well absorbed through digestion, so supplementation is the best way to prevent B12 deficiency" - American Journal of Clinical Nutrition 2001;71:514-522


    It would be just a killer to have the next number: "among vegans who eat supplements or eat fortified foods, less than 1% presented low levels of Vit B12"

    I'm pretty sure most, if not all, experts agree that if vegans (or non-vegans) take B12 supplements (not from multivitamins) matching their needs and their exposure to B12 antagonists (coffee, sugar etc), they wouldn't develop a deficiency unless there are special medical conditions involved.

    "Although vitamin B12 is obtained from meat, it's not well absorbed through digestion, so supplementation is the best way to prevent B12 deficiency" - American Journal of Clinical Nutrition 2001;71:514-522
    That may be true in an 'artificial' world, and affects both vegans and non-vegans, of course. In terms of B12 in vegan and non-vegan diets, these topics are at the heart of this discussion: Should we avoid everything man-made? (I don't think so). Would vegans need B12 supplements in a 'natural' world? (I don't think so). Does eating animal products a guarantee for getting enough bioavailable B12? (Obviously not.) If not trusting supplements represents a problem - shouldn't w also look at a much more important topic: Can we trust that a diet including animal products will keep us healthy? No, because lots of health problems are associated with - animal products!

    But please try Google... there are massive amounts of B12 studies out there. If you find studies suggesting that humans without any special medical conditions won't be able to avoid a B12 deficiency with what you call 'artificial' B12, please let us know!
    I will not eat anything that walks, swims, flies, runs, skips, hops or crawls.

  5. #5

    Join Date
    Jun 2012
    Location
    São Paulo
    Posts
    14

    Default Re: Can we trust B12 supplements?

    Korn,

    I was just watching a video of Prof. Colin Campbell

    http://video.google.com/videoplay?do...7765978236346#

    Starting at 8:37 he mentions a report summarizing many studies showing that supplements of vitamins A, C and E don't work.

    Nothing about vit. B12, but it supports the opinions out there that "supplements don't work at all"

    I didn't bother searching that report, since he didn't mention any name or organization envolved.

  6. #6
    Ex-admin Korn's Avatar
    Join Date
    Apr 2004
    Location
    Europe
    Posts
    4,830

    Default Re: Can we trust B12 supplements?

    Here's some info from T. Colin Campbell about B12. Make sure you read the whole article...

    http://www.tcolincampbell.org/course...2a4d1aa49002bc
    I will not eat anything that walks, swims, flies, runs, skips, hops or crawls.

  7. #7

    Join Date
    Jun 2012
    Location
    São Paulo
    Posts
    14

    Default Re: Can we trust B12 supplements?

    Thanks for the very interesting article.

    So, I think we can summarize and conclude from Dr. Campbell study the following:

    "The hypothesis that vitamin B12 is not found in a plant based diet is wrong. However, most B12 problems are usually not due to a low intake but due to a low absortion. Although vegans are shown to have less B12 concentration in their bloods, it is POSSIBLE that they also need less of it. So far, nothing has been said about the absortion impact of a plant based diet or a meat based diet. Therefore, to take a supplement of Vit B12 is a reasonable approach for everybody, just in case, unless you are willing to give a helping hand to the natural selection process and risk to be one of those that will present vit B12 deficiency symptoms due to low absortion"

    Unfortunately, he didn't mention anything about absorbability of B12 supplements :-/

  8. #8
    Ex-admin Korn's Avatar
    Join Date
    Apr 2004
    Location
    Europe
    Posts
    4,830

    Default Re: Can we trust B12 supplements?

    So, I think we can summarize and conclude from Dr. Campbell study the following:

    "The hypothesis that vitamin B12 is not found in a plant based diet is wrong. However, most B12 problems are usually not due to a low intake but due to a low absortion. Although vegans are shown to have less B12 concentration in their bloods, it is POSSIBLE that they also need less of it. So far, nothing has been said about the absortion impact of a plant based diet or a meat based diet. Therefore, to take a supplement of Vit B12 is a reasonable approach for everybody, just in case, unless you are willing to give a helping hand to the natural selection process and risk to be one of those that will present vit B12 deficiency symptoms due to low absortion"


    I don't think we can conclude that from Campbell's study, and furthermore: He is just scratching the surface of the (B12/vegan) topic, and admits - at the bottom of the page, that he still doesn't know if this view is right. The reason I posted the link is the last part:

    "I have been influenced by two of my clinician colleagues, Dr. Michael Greger and Dr. Alan Goldhamer, that their understanding of the literature and their experience in the clinic suggest that B12 deficiency may be seen in vegans, thus advocate B12 supplementation. I defer to their view" – suggesting that he dos not think B12 supplements have no value.



    Lot's of the stuff that has been written about B12 is confusing, and fail to take all the relevant aspects into consideration.

    Some examples:
    Victor Herbert, reported that "inadequate absorption [in the digestive tract] accounts for more than 95% of the vitamin B12 deficiency cases seen in the United States."
    When Dr. Herbert wrote what he wrote, he was probably thinking of the cases where people lived on a standard diet, which doesn't necessarily apply to vegans. As the Campbell article mentions:

    According to the Victor Herbert position, "There is no active vitamin B12 in anything that grows out of the ground
    Victor Herbert wouldn't know - because there most plants have never been properly tested for B12. However, he also said that small amounts of B12 (we need only small amounts) could be found in some root nodules.

    He also states that vegans thus can get adequate B12 from their food only if it is fertilized with human waste
    But Herbert also said that 95% of the B12 found in human waste was inactive B12 analogues!

    So: Professor Campbell: confused. Dr. Herbert, the anti-vegan, disagrees with himself – and "rely" on studies which don't exist. Dr. Mozafar: he never tested if the B12 found in plants was bioavailable/active for humans. Maybe this B12 would show up in blood tests in humans who consumed them, but the really interesting part is: would they prevent B12 deficiency, or would they be inactive?

    We already have articles about Dr. Herbert and the Mozafar study here, if you want to read more. The Mozafar study is also discussed here and here.

    Unfortunately, he didn't mention anything about absorbability of B12 supplements :-/
    There are many studies on this. Try PubMed.

    Testing if B12 supplementation - or B12 in plants – actually have an effect, is cheap and easy. Just try it! The most relevant test to take (in addition to the B12 test iself) to monitor B12 activity is a so called MMA test.

    So, to sum up and comment each of Campbell's conclusions:

    1. Contrary to the most recent U.S. Dietary Guidelines, B12 can be found in plants.
    Lots of plants contain B12, as shown in our B12 in plants? section. The only important thing we need to know is if it's active in humans.
    2. Organically grown plants contain higher levels of B12 than plants grown non-organically with chemical fertilizers.
    Sure. Good and important point. But see above. (Hi, Risker! ).
    3. Plant roots are able to absorb certain vitamins produced by soil microorganisms, thus suggesting that plants grown in healthy soil, full of microflora and microfauna, are more nutritious.
    Nutritious, yes - but see #1.
    4. Vegans - and anyone else - should be able to obtain B12 by consuming organically grown produce.
    "should be" isn't good enough. Until we can show that consuming the kind of B12 we find in the dozens of plants that are said to contain B12, this isn't really a conclusion...
    5. Evidence that plants obtain vitamins from the soil has been available for several decades.
    True. But see #1.

    Having said all that, I think professor Campbell is a great writer, and bringing up some necessary and important perspectives. Unlike Peta and The Vegan Society, Dr. Mozafar and many other experts, he emphasize the context we need to see the 'B12 for vegans' topic in.

    He writes:
    Are vegans really at greater risk of B12 deficiency? Some evidence says yes; some invites skepticism. Clearly, vegans do generally have lower blood concentrations of B12. A number of studies have shown this. But these low concentrations mean little unless there is a higher incidence of the accompanying blood (megaloblastic anemia) and nerve (parathesia) disorders, for which there seems to be little or no evidence. What should be acknowledged is that the concentrations of other blood factors, such as cholesterol, also are very different among vegans, and for very good health reasons at that. Why should we expect the lower B12 levels to be an exception?
    Re. the last sentence above, the maths are, IMHO, rather simple:
    1) Meat eaters are exposed to an 'unnatural' lifestyle, chlorinated water, food from poor soil etc, but eat animals, which to a certain degree (at least for ca. 25-50% of them) compensates for the poor access and absorption rate of true B12 in our 'sterilized' world.
    2) Vegans are also exposed xposed to an 'unnatural' lifestyle, chlorinated water, food from poor soil - and also sometimes consume a lot of sugar, tobacco, alcohol - are exposed to stress, polluted air and so on. All those reduce the B12 status in our bodies. But since we don't use meat or milk from, we may need to compensate for the unnaturalness of our lifestyle in some other ways. This could be by supplementation, or by trying to living very 'clean' lives accompanied by consuming non-animal sources of active B12 - and, being a sceptic to all theories, including my own, this should be followed up by monitoring the B12 activity in our bodies. It may not even help that the plants we consume are organic if they com from poor soil/polluted oceans. And B12 synthesis in plants have seen a peak after circa four days - plus, after a plant has been picked up from the soil, it is cut off from it's B12 source, so we could see that the B12 levels in plants are very dependent on how fresh they are. This shouldn't be a problem for wild animals living in a forest or jungle, and as we know - factory farm animals are given B12 supplementation when needed.

    To assume that vegans - unlike meat eaters - are untouched, B12 wise, by our world's soil/water/air (etc) status is just naive, and again: I haven't seen anything suggesting that B12 supplementation (not from multivitamins) don't work.
    I will not eat anything that walks, swims, flies, runs, skips, hops or crawls.

Similar Threads

  1. Trust
    By Terra'dantes in forum QUESTIONS FROM NON-VEGANS
    Replies: 10
    Last Post: Dec 10th, 2010, 10:50 PM
  2. Replies: 39
    Last Post: Oct 17th, 2005, 07:32 PM
  3. If you take B12 supplements...
    By Korn in forum Vegans and B12
    Replies: 20
    Last Post: Jun 26th, 2005, 11:52 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •