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    Default Interesting B12 article (from


    From: (Ted Wayn Altar)
    Subject: Vitamin B12 and Vegans
    Message-ID: <>
    Organization: Simon Fraser University, Burnaby, B.C., Canada
    Date: Thu, 14 Jan 1993 23:41:30 GMT
    Lines: 546

    >Michael Traub wrote:
    > B12 deficiency is more common in omnivores than in vegans.

    >Martin Hulsey replied:
    > Do you have a peer-reviewed reference from a bona fide nutrition
    > journal that says this? I have a couple that say quite the opposite.

    I have to agree with Martin in that I've not heard of this before
    either, but I have seen claims to the opposite. In a trivial
    sense, of course more omnivores incur B12 deficiency problems
    simply because there are more of them. Of course, this is not
    what is at issue. What we need are accurate incidence rates (and
    ideally breakdowns of the various causes of B12 deficiency) and
    this would require very large samples of people.


    Of course, maybe we need to qualify which "vegans" are clearly at
    risk and which one's might "theoretically" be at risk. First,
    consider some of the factors that are known to increase one's
    need for B12:

    (1). Meat or other animal products and refined carbohydrates
    (sugars) when used generously may more than double B12

    (2). Persons who use drugs, chemical, or beverages which
    destroy B12 (e.g., tobacco, alcohol, caffeine, etc.)

    (3). Megadoses of vitamin C may produce B12 deficiency by
    destroying the cobalamins during transport through the
    gastrointestinal tract (Hines, 1975). Quantities more
    than 1/2 of a gram can destroy 50% to 95% of B12 in
    the food.

    (4). Oral contraceptives are used (affects the B12 binders
    of the blood).

    (5). egg albumin and egg yolk decreases B12 absorption

    (6) intestinal parasitism (e.g., tapeworms) and explosively
    growing bacterial floras can effectively compete with
    the host for the vitamin

    Given these factors that do increase need, it is apparent that
    meat eaters do need more B12, but presumably this is adequately
    compensated for by the fact that they consume more dietary B12.
    It is of course possible that the compensation may not be great
    enough. Rather than only speculate, however, upon a
    "theoretical" deficiency, it would be best to have in hand some
    actual actuarial data documenting from large samples the relative
    rates of B12 deficiency disease among omnivores as compared to
    vegans. So far, I've not seen any such actuarial data compiled.
    But this is understandable when we keep in mind that B12
    deficiency is actually rare and of the cases occurring 95% of
    those cases are not due to a simple dietary deficiency but rather
    to physiological absorption/utilization problems.


    There are, however, amply studies (see Chanarin et al., 1985;
    Dagnelie et al, 1989a; Dagnelie, 1989b) upon some groups of
    vegans whose young children and infants are documented to show
    an higher than expected incidence of the signs and symptoms of
    B12 deficiency (see references below). This concern for the
    children of some fad vegetarians that should be seriously noted.
    There is enough evidence (see references below) to here warrant
    concern that some vegan groups do incur a risk of B12 deficiency
    among their young children. In particular, vegetarian groups
    prone to certain "fad" vegetarianism like that of macrobiotic or
    crudivore diets, seem to sometimes (again, not consistently) have
    a higher incidence of B12 deficiencies among their young

    Why certain vegetarian diets or practices seem to incur this
    problem is not yet understood. The heavy use of nori, for
    instance, could be one explanation. The problem with algae
    sources like spirulina or nori is not only that they are low in
    what is being NOW measured as B12 by newer methods (see Herbert,
    1988) but that it may not be a true B12 but possibly contains
    what has been referred to as noncobalamin analogues of B12 that
    might actually interfere with the absorption of true B12. In any
    case, "B12" from spirulina or nori, if it is true B12, is simply
    NOT bioavailable (see Dagnelie, 1991). Another possible
    explanation would be the "explosive" growing of bacterial floras
    that can be stimulated by certain very high fiber diets (which
    would characterized the extreme macrobiotic diets of eating only
    cereals, particularly rice, which are high in the slowly
    fermentable fibers that most readily promote microbe

    In any case, to err on the side of caution, certainly lactating
    vegetarian women and young vegan children should certainly take
    some supplements. The Nutrition Standing Committee of the
    British Paediatric Assoc recommended in its special report on
    vegetarian weaning (ARCHIVES OF DIS. IN CHILDHOOD, 1988,
    63:1286), for instance, recommended B12 supplements at weaning
    and for breast feeding vegan mothers.


    Now, before we consider the more controversial question about
    whether or not adult vegans have an higher incidence of B12
    deficiency disease than omnivores, it might be helpful to keep in
    mind some of what is known about about B12 needs.

    Now, the amount of B12 actually needed by the body is incredibly
    small and the RDA level is of course more than you need, due to
    considerations for a safety margin but also because of the
    measurement problem for small amounts of B12 and the consequent
    assessment of now much B12 is really necessary for human beings.
    The National Research Council recommends 3 micrograms (3
    millionths of a gram) per day to meet the body's needs. Victor
    Herbert, who is probably the leading authority on B12, suggests
    that 1 microgram would be a better RDA, and he puts the actual
    requirements of *absorbed* B12 to be round .1 microgram/day
    (hence, the NRC recommendation may in practice be some to 6 to 30
    times greater than our actual requirement).

    Absorption of the vitamin also decreases with increased intake.
    At low levels of intake the mean absorption is 70% (even higher
    for people with low serum levels of B12), but at high intake
    levels the absorption rate drops to about 16%.

    The fact of the matter is that you need very little and your body
    can store the stuff for 3 to 5 years. Hence, you simply don't
    need to consume B12 every day. Another point maybe to keep in
    mind is that researchers really don't know how much low levels of
    B12 is in our foodstuffs since their is not yet a sensitive
    enough assay for trace amounts of B12.

    The main rout of loss of bodily B12 in the bile, while most of
    the bile is effectively reabsorbed (more than 90%), some is not
    thereby making for a loss of B12 (about .1 microgram/day).
    Because vegans generally eat less fat and no cholesterol, their
    production of bile is less and it is therefore likely that their
    need for B12 replacement would also be less.


    It is true that cultured sources may have little or no
    B12, but this depends on the culturing process. Nutritional
    yeast, for instance, if cultured under controlled conditions
    so stringently that no bacteria is allowed to grow
    along with the yeast, then indeed there will be no B12, since the
    only source in nature is from bacteria (incidentally, I have
    been told that the gene for B12 from bacteria could theoretically
    be cloned onto nutritional yeast so that we could then not only a
    tasty yeast but one with more than enough B12). Some nutritional
    yeasts, may use a B12 rich feed for the yeast, in which case the
    yeast would then be a good source of B12.

    It has been reported that B12 is to be found on the roots and
    stems of tomatoes, cabbage, celery, kale, broccoli, and leeks.
    Victor Herbert, however, found that "well washed" plant foods
    contain no B12 except for trace amounts in some rhibozium-
    bacteria-containing root nodules.

    Some recent dietary intake studies of vegans showed them to be
    consuming, (including B12 from fortified foods like certain soya
    milks and margarines) an average intake of 1.2 -1.8 micrograms
    (Carlson et al., 1985; Sanders et al., 1987; Rana et. al.). In a
    Swedish study where fortified foods were not used, the average
    intake of .35 micrograms was recorded (Abdulla et al., 1981).
    Gill Langely (1988), in his fine survey of the research on vegan
    nutrition, reports a study indicating British vegan pre-school
    children had a mean intake of 280% of the British RDA (but 5 did
    have intakes less than the recommended intake (Sanders, 1981).
    An U.S. vegan community that used supplemented soya milk and
    yeast, had mean intakes of 15 micrograms or about 660% of US RDA
    for children. In none of the above groups were any clinical
    signs of deficiency found.

    Maybe a more important consideration than what is to be found in
    our foods is that much vitamin B12 is actually produced by the
    body itself. Bacterial flora in the gut, but also bacterial
    growth in the mouth, around the teeth and gums, in the
    nasopharynx, around the tonsils and tonsillar cypts (another
    reason not to remove tonsils if possible), in the folds at the
    base of the tongue and even in the upper bronchial tree can
    produce B12.

    It is known that the B12 is produced in huge amounts in the colon
    (5.0 micrograms/day), though it doesn't seem that it can be
    absorbed through the walls of the colon. The small intestine,
    however, can absorb B12 and indeed some B12 producing bacteria is
    to be found there. It is possible that enough intrinsic factor
    enters the small intestine still sufficiently active to bond with
    B12 for absorption. It is also possible that vegan physiology
    enables a more ready absorption (or lower need?), than
    theoretically expected. Who knows? What we do know that
    people's ability to absorb many nutrients increases as one's need
    for those nutrients increases. For example:

    ". . . vegetarians appear to "undergo physiological
    adaptation enabling them to make somewhat better utilization
    of iron than would be expected from iron bioavailability
    studies involving the feeding of vegetarian diets to
    omnivores or involving the testing of particular components
    characteristic of vegetarian diets with omnivore subjects."
    (from Kies & McEndree "Vegetarianism and the
    bioavailability of iron" in Kies (ed.) NUTRITIONAL

    Hence, we must exert some caution in extrapolating the
    nutritional needs and adaptive capacities of omnivores to that of
    vegans. Better, therefore, to look at the DIRECT evidence of
    vegan health or deficiency.


    Vegetarians who are not vegans but still consume milk products
    and eggs, probably not need to worry about B12 deficiencies.

    Indeed, it is not evident that sensible adult vegans actually
    suffer from a greater incidence of B12 deficiency than do
    omnivores. If one eats a variety of food products, consumes
    fresh vegetables and is not on antibiotics, then the B12 being
    produced by bacteria in the gut and the trace amounts from foods
    may well be sufficient. The direct evidence for this comes from
    those studies that have actually tested vegans to see if B12
    deficiencies turn up. In general, the results uniformly indicate
    that even in the case of those vegans who for decades have not
    taken any supplements they still appear to have adequate B12
    levels. While the serum levels of B12 tend to be lower than that
    of an omnivorous control group, hematologic evidence of vitamin
    B12 deficiency is not present.

    As Gill Langely reports:

    Accepted normal serum levels fall within a wide range -- from
    100-900 pg/ml. Values below 80pg/ml suggest a possible
    deficiency of B12 while between 80 and 140pg/ml there may or
    may not be symptoms of deficiency. LOWER THAN NORMAL SERUM
    DEFICIENCY. As already mentioned, vegans of up to 20 years
    standing with no obvious source of the vitamin in their diets
    only very rarely have clinical symptoms of deficiency.
    Although their serum level of B12 does fall over a number of
    years it often stabilizes at about 100pg/ml. Vegans who take
    supplements or fortified foods generally have higher serum
    levels of the vitamin, while VEGAN MACROBIOTICS OR SMOKERS

    Consequently, surveys of vegans document a wide variation of
    serum levels of B12. On report (Ellis, 1967) mentions values
    between 30 and 650 pg/ml with a mean value (of 20 subjects)
    of 236pg/ml, compared with a range of 120-740pg/ml and a mean
    serum value of 441 pg/ml in matched omniovre control
    one 80-year-old subject who had been a vegan for only 2 years
    had pernicious anemia. Three vegans who had been on the diet
    for 17 years without taking supplements were healthy, with
    serum B12 levels of 150, 375 and 450pg/ml, and normal amounts
    of haemoglobin in the blood.

    Haematological measurements (Sanders it al, 1978) of 34
    vegans who had been on the diet for between one and 30 years
    revealed a range of serum B12 levels from 94-675pg/ml -- all
    ABOVE the value of 80pg/ml at which deficiency symptoms can
    be expected. The majority of subjects took B12 tablets or
    food fortified with the vitamin, and those who did had higher
    amounts in their blood. THE SERUM LEVELS OF THREE SUBJECTS
    SOURCE OF B12 WERE ALSO ADEQUATE, at 120-230pg/ml. All the
    vegans were healthy, none showed symptoms of B12 deficiency
    and all had normal haemoglobin values. The same report lists
    other surveys of vegans which have failed to show symptoms of
    dietary deficiency of B12. [emphasis his]

    Given what conservative authorities have to say in theory about
    B12 (especially those that would undertake an analysis of the
    composition of a vegetarian diet), we should expect to see a
    greater incidence of B12 deficiency in vegans than in non-vegans,
    yet there is no such difference as far as I know.

    Of course, people will cite some case studies of some unfortunate
    vegans but such case studies are limited in that we don't have a
    proper comparison with non-vegans and by now it should be
    apparent that many other causes besides dietary deficiency can be
    at fault. If one looks at these case studies closely, the
    individuals are often reported as having other deficiencies
    thereby undermining the very point that such cases might thought
    to have illustrated in the first place.

    What is interesting is that B12 is so extremely rare that even
    single case studies get published, but the generalizability of
    such case-studies to the general population of vegans is not to
    automatically be undertaken. More evidence than this is needed,
    especially when the confound of physiological
    aborption/utilization problems are often not properly ruled out
    in these case studies.


    Let it again be said, however, that B12 deficiency is "rare"
    among vegans and that over 95% of deficiency problems are not due
    to a simple intake inadequacy but are due to an malabsorption
    problem. the development of a serious B12 deficiency is not a
    simple or well understood matter but it is known that absorption
    and conservation of B12 in the body is more important than how
    much is to be found in the diet.

    known causes of malabsorption are a lack of intrinsic factor
    (e.g., due to pernicious anemia, destruction of gastric mucosa,
    etc.), removal or disease of the second portion of the ileum,
    competition for B12 by microorganisms or intestinal parasites,
    toxic substances, etc.

    beside malabsorption, there are also possible problems (see
    herbert, 1973) in utilization (e.g., enzyme deficiencies, liver
    or kidney disease, etc), increase loss (e.g., renal disease) or
    for an increase requirement (e.g., hyperthyroidism, lactose

    still, if one has an absorption, loss, or increase need problem,
    then presumably when little B12 is available in the diet then
    still less is going to be assimilated. now, what can vegans do
    to prevent a B12 deficiency?


    Fresh garden pricked vegetables, particularly root vegetables,
    that are not overly scrubbed cleaned or pealed will have some b-
    12 on their surface. Boiling such vegetables and then throwing
    out the water would make for a loss of this B12.

    Since B12 is predominantly produced by bacteria (no animal
    produces its own), then foods grown in soils where the bacteria
    flora is rich would presumable have more B12 on their surface.
    Hence, organically grown foods will probably be richer in B12.

    There is now some recent evidence (Combs, 1991) that some peas
    and bean actually produce their own B12. It was previously
    thought that the only source in nature was bacteria. This would
    suggest that such peas and beans would have their B12 throughout
    rather than just on the surface. Still, this probably will not
    suffice as a single plant source to provide sufficient B12.

    A simply but useful recommendation is to chew one's food properly
    and leave plenty of time between meals helps absorption. The r-
    binders in saliva help to hold onto the B12 in the food until it
    reaches the small intestine where it absorbed (Fleming, 1978).


    Multivitamin preparations containing B12 is probably not a good
    idea. Besides consuming so-called vitamin "d" which most people
    do not need and which has been implicated in helping to cause
    arteriosclerosis and osteoporosis, these preparations contain
    breakdown products of B12 that can actually have an anti-B12
    effect. Hence, multivitamins may contribute to the very
    deficiency that they were supposed to correct. Victor herbert
    (1962), the leading authority on B12, reported that all of the 10
    multivitamin-mineral products that he tested showed anti-B12
    breakdown products. Tests for B12 in the blood unfortunately
    cannot discriminate between the true vitamin B12 and its
    breakdown products.

    For healthy adult vegans I do think we should be careful about
    recommending routine B12 supplements. Even though complete
    absorption is not likely, the dosages are probably still too high
    (1200 mcg). There is some case studies and experimental evidence
    that an excessive B12 consumption encourages cell division in
    general and certain tumor cells in particular (bergevin et al.,
    1976; chauvergne, 1970).

    In general, use of B12 supplements should be certainly be
    considered by pregnant and lactating women, young infants and
    children, the elderly and vegans not in good health or who still
    smoke. Serum levels of B12 are lower for smokers than non-
    smokers (this may be an effect of the cyanide content of tobacco
    smoke, which the body attempts to detoxify by a means that
    unfortunately uses up the stores of B12).

    Non-smoking, healthy adult vegans who eat sensibly, are not on
    medications (e.g., antibiotics) and who do not daily drink
    alcohol probably do not need to take supplements. If such vegans
    are going to take supplements, then they should probably not take
    them on regular basis since the doses are too high.

    Individuals even on conventional diets (diets high in fat and
    animal protein which increase the need for B12) still only need
    about 1 mcg per day according to Victor Herbert (recent revision
    of RDA recommendations has lowered the amount from 3 mcg/day to 2
    mcg/day). Maybe half of a typical 1000 mcg pill about once month
    would be more than sufficient. Finally, vegans and non-vegans
    should make sure that their B12 supplements are derived from
    bacteria cultures and do not contain spirulina or nori.

    If one has been a vegan for a many years, it might be a good idea
    to have one's serum B12 levels checked. The normal range is
    about 150-750 pg/ml according to the merck manual. Others put it
    at 100-900 pg/ml. There is no exact cutoff. Vegans, of course,
    will have levels at the low end but this by itself is not a cause
    for alarm. After all, the "normal" range is based upon research
    from an omnivorous population and vegans do have a lower need for
    B12 and are more efficient at preservation of extant stores.
    indeed, it could be argued that the "true normal" range might
    well closer to that of vegans. The "ideal" physiological
    functioning has yet to be determined, but we do know that almost
    all investigators reporting on vegans report them as being above
    average in health and more active.


    Look, I don't wish to deter any adult vegans from taking B12
    supplements. They certainly can't do any harm and one doesn't
    have to take them that often. Better to err, even if it is
    needless error, on the side of caution. Also, there are now
    plenty of B-12 fortified foods.


    REFERENCES 1: General

    Abdulla et al. (1981). Nutrient intake and health status of
    vegans Chemical analyses of diets using the duplicate portion
    sampling technique. AM. J. CLIN. NUTR., 34:2464-77.


    Bergevin et al, (1976). Pernicious anemia terminating in acute
    myeloblastic leukemia. SOUTHERN MEDICAL JOURNAL, 69:110.

    Carlson et al. (1985). A comparative evaluation of vegan,
    vegetarian and omniovre diets. J. PLANT FOODS, 6:89-100.

    Chauvergne, J. (1970). The risk of administering vitamin B12 to
    cancer patients. SEMAINE DES HOSPITEAUX PARIS 46:2170

    Combs, Gerald (1991). VITAMINS: THEIR ROLE IN NUTRITION &

    Dagnelie et al. (1991). Vitamin B12 from algae appears not to be
    bioavailable. AMER. J. OF CLINICAL NUTRITION, 53:695.

    Fleming, A. (1978). Serum vitamin B12 levels and vitamin B12
    binding proteins of serum and saliva of healthry Nigerians
    and Europeans. AMERICAN J. OF CLIN. NUTRITION, 31:1732.

    Hector & Burton (1988). What are the psychiatric manifestations
    of vitamin B12 deficiency? JOURNAL OF THE AMERICAN
    GERIATRICS SOCIETY. 36(12):1105-12,

    Herbert, V. (1962). Harmful B12 breakdown products in
    multivitamins? MEDICAL WORLD NEWS, (Sept. 28):12-13.

    Herbert, V. (1973). The five possible causes of all nutrient
    deficiency: Illustrated by deficiencies of vitamin B12 and
    folic acid. AMER. J. OF CLIN. NUTRITION, 26:77.

    Herbert, V. (1988). Vitamin B12: plant sources, requirements,
    and assay. AMER. J. OF CLINICAL NUTRITION, 48(3):852.

    Hines, J. (1975). Ascorbic acid and vitamin B12 deficiency. J.
    OF AMER. MED. ASSOC., 234(1):24.

    Thrash & Thrash (1982). NUTRITION FOR VEGETARIANS, 1982.

    REFERENCES 2: Group comparison studies involving adult

    Bar-Sella et al. (1990). Vitamin B12 and folate levels in long-
    term vegans. ISRAEL JOURNAL OF MEDICAL SCIENCES. 26(6):309

    Ellis & Montegriffo (1970). "Veganism, clinical findings and
    investigations. THE AMER. J. OF CLIN. NUTR., 23(3):249.

    Ellis & Mumford (1967). The nutritional status of vegans and
    vegetarians. PRC. NUT. SOC., 26:205-12.

    Ernst et al. (1986). Blood rheology in vegetarians. BRIT. J. OF
    NUTRITION, 56(3):555.

    Rana et al. (1986). Taurine concentratins in the diet, plasm,
    urine and breast milk of vegans compared with omnivores. BR.
    J. NUTR., 56:17-27.

    Sanders et al. (1977). Haematological studies on vegans. BRIT.
    J. OF NUTR., 40:9

    Sanders, T. (1978). The health and nutritional status of vegans.
    PLANT. FDS. MAN, 2:181-93.

    Sanders & Purves (1981). An anthropometric and dietary
    assessment of nutritional status of vegan preschoold
    children. J. HUM. NUTR., 35:349-57.

    Sanders et al. (1987). Blood pressure, plasma renin activity and
    aldosterone concentration in vegans and omnivore controls.
    Hum. Nutr.: Appl. Nutr., 41A:204-11

    Smith (1962). Veganism, a clincal survey with observations of
    vitamin B12 metabolism. THE BRIT. MED. J, 1(June 16):1655.

    Wokes et al. (1955). "Human dietary deficiency of vitamin B12.
    THE AMER. J. OF CLIN. NUTR., 3(5):375

    REFERENCES 3: Studies involving some vegetarian children
    indicating the presence of B12 deficiency.

    Chanarin et al. (1985). Megaloblastic anaemia in a vegetarian
    Hindu community. LANCET, 2:1168

    Dagnelie et al. (1989a). Nutritional status of infants on
    macrobiotic diets aged 4 to 18 months and matched omnivorous
    control infants: a population-based mixed-longitudinal study.
    Weaning pattern, energy and nutrient intake. EUR. J. CLIN.
    NUTR., 43:311.

    Dagnelie it al. (1989b). Increased risk of vitamin B12 and iron
    deficiency in infants on macrobiotic diets. AM. J. CLIN.
    NUTR., 50:818."
    I will not eat anything that walks, swims, flies, runs, skips, hops or crawls.

  2. #2

    Default Re: Interesting B12 article (from

    That brought to light some things I didn't know. I was consodering taking suppliments myself but I didn't. After reading the article I am glad I didn't take them. The reason being my personal physiology. I have often felt more calm about things than other poeple aven when it was expected.

    I have heard that vitamin B 6 and 12 calm humans down, but I seem to be overly calm all of the time. It may also be due to lack of energy from not eating enough. Thanks for the article!

  3. #3
    Ex-admin Korn's Avatar
    Join Date
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    Default Re: Interesting B12 article (from

    The article contains a lot of interesting stuff, but wouldn't see it as a definite argument against using supplements... B12 is a tricky vitamin, and people who consume little or no B12 (vegans or not) should IMO not ignore that they may become deficient... not because B12 never is found in plants, but because there are so many B12 'killers' out there.
    I will not eat anything that walks, swims, flies, runs, skips, hops or crawls.

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