Response to: Vegan Vitamin B12 Deficiency is a Myth

On Saturday, August 21, published an article by Cindy Jones-Shoeman, Vegan Vitamin B12 Deficiency is a Myth.

The article starts out by saying that “nothing could be further from the truth” than the idea that vegans can suffer a B12 deficiency from their diet.

The article by Jones-Shoeman appears to be a rehashing of an old article (apparently from 2004 or earlier) by Vivian Vetrano, “Rethinking & Clarifying the Vitamin B12 Issue” which appears on the Rest of Your Life Retreat website:

Although Vetrano’s article is one of the most fanciful stories I’ve ever read about vitamin B12, it is rather detailed and I will only respond to the excerpts from the Jones-Shoeman article:

“According to Dr. Vivian V. Vetrano, vitamin B12 actually comes from coenzymes, which are already present in bacteria found on the human body (in and around the mouth, for example).”

Vitamin B12 does not come from co-enzymes, it is a co-enzyme. Bacteria do produce vitamin B12, but there is no proof that bacteria living in most people’s mouths produce active vitamin B12 or produce it in amounts large enough that it could prevent B12 deficiency. This is underlined by the fact that many vegans develop full-blown vitamin B12 deficiency, and in some cases permanent neurological damage, as can be seen here: In addition to those cases in the scientific journals, I have known many vegans who have suffered from B12 deficiency and cured it by supplementing with cyanocobalamin (the most stable form of vitamin B12).

About a dozen studies have correlated low vitamin B12 levels in vegans with elevated homocysteine levels. Elevated homocysteine levels have been linked to early death, primarily from cardiovascular disease, and Alzheimer’s Disease. More details on that are at

“In fact, vitamin B12 deficiency is often, according to Dr. Vetrano, a symptom of a larger problem; that is, it’s not caused from a poor diet but rather from deficiency diseases…”

While it is true that about 2% of the population has trouble absorbing vitamin B12, the vast majority of problems that have been seen in vegans have been caused by a low B12 intake, not from absorption problems.

“Vitamin B12 deficiency due to a vegan diet is simply a lie that finally needs to be put to rest.”

Unfortunately, this could not be further from the truth. The most common, serious damage that results from vitamin B12 deficiency is when a pregnant vegan who does not supplement has a baby who also does not get any B12 supplementation. Typically, around 6 months of age, the infant’s growth and neurological development ceases and then begins to regress. In many cases, such infants have sustained permanent brain damage.

Vitamin B12 deficiency among vegans is real and is not something to be flippant about. It is so important that a number of vegan health professionals and organizations have endorsed an open letter to the vegan community, What Every Vegan Should Know about Vitamin B12 ( This letter has been signed by The Vegan Society (UK), Vegan Outreach, and many members of the International Vegetarian Union science group.

82 Responses to “Response to: Vegan Vitamin B12 Deficiency is a Myth”

  1. Nicola Qureshi Says:

    “What Every Vegan Should Know about Vitamin B12” suggest 2000 micrograms weekly… I assume this is for adults. How much should I be giving my son (he is 5)?

  2. Jack Norris RD Says:


    It’s somewhat arbitrary since there haven’t been studies done on weekly amounts for vegan kids. I’d give him 250 mcg, three times per week.

  3. Nicola Qureshi Says:

    I figured as much. Thanks for your help! 🙂

  4. Devin Says:

    What are some early signs of b12 deficiency? Are there any foods that inhibit b12 absorption? Are there foods that enhance b12 absorption?

  5. Jack Norris RD Says:


    1. They are listed here:

    2. No.

    3. No.

  6. beforewisdom Says:

    I’m stealing and paraphrasing this from a well known vegan adovacate, but one of the first signs of a vitamin b-12 deficiency is crazy talk about not needing to get vitamin b-12 🙂

  7. Sarah Says:

    Do you have a favorite brand or brands of b-12? I used to use solaray sublingual and they lasted a long time under the tounge, but found that twinlabs sublingual is cheaper (at our local store), but it dissolves so quickly I wonder if that negatively impacts absorption? Thanks!

  8. Jack Norris RD Says:


    I don’t have a favorite brand. Chewing the tablet up good should ensure proper absorption.

  9. harley Says:

    Ive trained/race with the best in cycling. They ALL do b12 injections on a regular basis and NONE of em are vegan.

    What is the biggest demographic group of b12 supp takers?: mainstream bodybuilders and they also eat the largest amounts of animal products.

    Personally I feel everyone can get some benefit from taking a b12 supp as we live in such a sterile world thesedays. We put b12 in dog, cat, fish food. Just read the packaging next time your at the supermarket.

    I didnt supp for years cos I thought it was ‘unatural’ but in hindsight, living in this society is unatural and a b12 supp is like a ‘getting back to nature’ ticket healthwise.

    Ive got a lot of raw meat eating mates and we get their b12 serum levels checked and they are all borderline deficient or deficient in b12.

  10. Reijo Laatikainen Says:

    Great post. I’d like to add that there is sound scientific evidence from UK that has demonstrated that 50 % of vegans can be considered as B12 deficient ( “Half of the vegans were categorized as vitamin B12 deficient and would be expected to have a higher risk of developing clinical symptoms related to vitamin B12 deficiency.”) Gilsing AM, et al. Eur J Clin Nutr. 2010 Jul 21

  11. Jack Norris RD Says:


    Although they were just recently reported, the B12 levels in that study were measured from 1994 to 1997 with some follow-up measurements in 2001. This was before many vegan nutritionists made a push to get the vegan community to recognize the need for B12. We hope things have improved a lot since then.

  12. Marya Says:

    Well, now I feel silly. I foolishly assumed that my daily multivitamin was giving me adequate B-12; I mean, it says on the bottle, “100% of daily requirement.” Yet the actual amount/pill is only 6mcg! Which means I’m only getting 42mcg/week (not counting whatever I get through food), right? Yikes. Do you agree, then, that adults should be getting 2000mcg/week?

  13. Jack Norris RD Says:


    The less often you get B12, the more you must take. Here are my recommendations for taking it on a daily basis:

  14. Valentin Says:

    “Preliminary evidence suggests that vitamin C supplements can destroy dietary vitamin B12. … Clinical significance is unknown, and it can likely be avoided if vitamin C supplements are taken at least two hours after meals.”

  15. Laurie Says:

    In regard to nutritional yeast, you list redstar and twinlabs as being fortified. I have seen Bob’s Red Mill listed as fortified/vegetarian support. is it the same as Red Star? I know that you don’t recommend it as a sole source of B12 but I loved the stuff and would like to have an idea if what I’m eating has any B12 in it so I can make decisions about what/how much other supplements to take.

  16. Jack Norris RD Says:


    Not all Red Star yeast is fortified. If the package doesn’t say it’s B12 fortified, then you should assume it isn’t. If there is no packaging, you should assume it isn’t fortified. Not sure about Bob’s Red Mill.

  17. Aimee Says:

    I’m so glad you wrote about this. Some fellow vegans have posted it (the original article) on their Facebook pages and I got worried that people would take it as gospel. It is such a serious issue- you don’t mess with the brain!

  18. Reijo Laatikainen Says:

    Thanks a lot for your response to my comment. I could not imagine that almost ten years old data is published but your right. In a cross sectional setting this old data does not as much value.

  19. Patrick Says:

    After about 2 1/2 years being vegan I was sent to a neurologist for a b-12 deficiency. I had lightheadedness when getting up sometimes my heart would race and feel like I was about to black out. I had numbness in my fingers from nerve damage (they did a nerve test), my left shin was very sore, I was very tired irritable and white spots of dry skin on forearms. My neurologist did not spend much time with me, his patients are pushed along like cattle with many months between appointments. I supplemented with sublingual losenges and after about a year I almost recovered. Now the symptoms are coming back, I am supplementing about 2,000 mcg or more per day. I have no more health insurance. My theory is this……I think alcohol flushes the B-12 out of my liver. Do you agree? I quit drinking alcohol and continue supplementing. I am hoping for the best. I am concerned about my heart as a result. I wish there was a natural way to get b-12 without having to supplement.

  20. Jack Norris RD Says:


    I’m sorry to hear about your problems. Have you been supplementing with sublingual lozenges every since your first diagnosis of B12 deficiency? How often?

    How long have you had your latest bottle of B12? You might want to get a new bottle just to make sure the one you have isn’t too old or was messed up in some way.

    To answer your question, I have never seen any research suggesting alcohol flushes B12 out of your liver.

  21. Patrick Says:

    No I didn’t always supplement with sublingual losenges. I was taking a multivitamin. When I became aware of the deficiency I started the losenges. It took a while to diagnose. At first they were sending me to a hemotologist for tests because my white blood cell count was getting low. The hemotologist found nothing wrong. I started the sublingual losenges and noticed a slow but steady improvement. I notice when I drink alcohol the symptoms seem to worsen.Mthylcobalamin, cyanocabalamin, nutritional yeast, fortified milk (soy or coconut), and bee pollen is where I get my b-12. I have had fresh bottles. Thank you for your reply.

  22. Jack Norris RD Says:


    I don’t know what more to tell you then. If your b12 levels are good then the problem must be with something else. You might want to cut back on the B12 supplements to a more normal level of supplementation, like 10 to 25 mcg per day.


  23. Sandra Brigham Says:

    Patrick – I was diagnosed with B12 deficiency a couple years ago. I’m not vegan, have not had surgeries to warrant it and IF is fine.

    Sublingual lozenges (1000 mcg/day) restored my levels (blood tests) w/i one year.

    I used to fall asleep at work in the afternoons, had horrible thigh muscle heaviness, couldn’t run my daily 6 miles, or walk the dog for more than 20 minutes for that matter, had neuro problems (balance, spatial depth problems, tingling, etc.)

    Fortunately, the supp resolved everything except ongoing fatigue and, like you, feeling wiped if I have alcohol. Interesting to hear someone else is experiencing the same thing as me!

    It’s the strangest thing. I had no problem with light wine drinking over the years (45yo) and then, concurrently with B12 fatigue, I couldn’t handle any alcohol. I would be wiped for 2-3 days after one glass of wine. I wonder if the wine does alter B12 accumulation in the liver. But how would we even test for that… B12 levels are blood tests.

    Liver cancer does run in the family so maybe the alcohol is correlational and not causative. Any liver cancer in your family?


  24. Patrick Carr Says:

    Sandra, thanks for sharing. I have had no liver cancer but my father had kidney cancer. I am convinced that alcohol can prevent absorption of many vitamins including b-12 and there is a direct correlation with drinking alcohol and b-12 symptoms getting worse. I don’t think I need a test, I think I know now. I have cut out alcohol and it seems my b-12 symptoms are under control. I am glad to hear that supplementing has improved your b-12 condition. On a more positive note, I have noticed since I became vegan my immune systom has gone through the roof. I never get sick anymore. Not even a cold. There have been times where my whole family was sick and I was surrounded by it and thought I would catch it too but I don’t. It has been about 6 years now. I will be 46 next month and I am the healthiest I’ve ever been. I give credit to fresh fruits and vegetables.

  25. Amy Says:

    It is SO irritating that I constantly see people on Twitter and Facebook perpetuating this idea that there is Vitamin B12 in unwashed produce, and spirulina and vegans don’t need to worry. Plus there is no point in arguing with them since they get all of their information from raw food gurus who think we can all live on nothing but bananas and air.

  26. Manish Verma Says:

    Dear Mr. Norris,

    I have been vegetarian all my life. I am trialing to be vegan now. I was referring to your link :-

    I am unsure how to interpret the table on B12. The US RDA (µg) is 2.4, while the Daily Dose (µg) is 25 – 100, which is 10 to 40 times the RDA. So are we supposed to take the RDA (2.4) or the Daily Dose (25-100)?

  27. Jack Norris RD Says:


    Because people can only absorb a small amount of vitamin B12 at one time, the doses for taking once a day or once a week (or even twice a day) are much higher than the RDA. You also might be interested in this:

  28. Lady Says:

    Oh thank you, just found this blog post of yours, so I don`t have to worry about Cyanocobalamin ( )

  29. Chrissy Says:

    I have been vegetarian since I was under 10 and became vegan almost 5 years ago. I do not supplement, I rarely eat fortified foods, I have had 4 healthy pregnancies (2 of them while vegan) and all of the boys are healthy vegans. I recently had blood work and it did not show any deficiency. I am not saying this to be argumentative but just to put it out there.

  30. Jack Norris RD Says:


    Many people haven’t been as lucky as you. Did you have your homocysteine or MMA levels checked?

  31. manbearpig Says:

    Do the martial artists at the schools in China take supplements everyday? Because most of them (maybe all) don’t eat meat.

    I seem to think it’s due to people’s diet before they became Vegan. Acidic foods, chemicals and all kinds of crap damaging the body. books have some nice info on acidic diets damaging bacteria in the body and they say it takes a while for the good bacteria to build up again after changing to a plant diet.

  32. manbearpig Says:

    This whole B12 is a fantastic way to keep you all on the drip.

  33. Jack Norris RD Says:


    Studies of B12 levels among raw foods vegans have shown them to be just as B12 deficient as any other group of vegans who do not supplement. You can read more here.

    > This whole B12 is a fantastic way to keep you all on the drip.

    Actually, it’s not.

  34. Ishai Silencio Says:

    Can we learn anything from our vegan animals like the elephant or the giraffe? They seem to be needing b12 as well, but where do they get it from?

  35. Jack Norris RD Says:


  36. curious Says:

    is vegan a lifestyle choice, a religion, an advocacy group, or …
    After how many decades will there begin to be measurable evidence – i.e.: life expectancy – that vegans (or vegetarians) benefit from their choice? Diatribe posted by adherents in the likes of wikipedia does not qualify. My blood pressure has hovered consistently WELL below 120/80 for over two decades, last three measurements around 100 over 60 (that’s not a typo) and I consume meat or fish just about daily. However, I am a “careful” eater, I do not consume the likes of fried foods, and have never smoked. I also put 100 miles on the bike weekly. Vegetarianism is likely conducive to better health because it seems to make the practicioner more nutritionally aware, otherwise I remain convinced that it is nonsense, while veganism may be dangerous. If it is a religion, or a preferred lifestyle, then fine, go for it. However, I do wish somebody would start producing some independent research to settle all the nonsense such as the B12 related nonsense spewed by “true believers”.

  37. Jack Norris RD Says:


    I’d be the first to say that you don’t have to be vegan to have good health. But, that said, on average vegans have very low cholesterol levels, rates of diabetes and hypertension, and body mass indexes. You can see the research here:

    We will probably have some good measurements of vegan mortality within the next 10 years coming out of EPIC-Oxford and Adventist Health Study-2 cohort studies.

  38. JD Mumma Says:

    Bravo Jack for continuing to get the research and truth/facts out about B12!!!

    Here is my B12 allegory using Gas Station Attendant = GSA and (fuelish) Car Driver = CD

    GSA: Do you need some gas?
    CD: No, I don’t have any symptoms of being low on gas.
    GSA: Yes, but you won’t have any symptoms till it is to late.
    CD: Yes, but I have no symptoms.
    GSA: What does your gas gauge show you? (testing for MMA, homocysteine, holotranscobalamin…)
    CD: I took out my gas gauge because my reasoning is that if they didn’t have gas gauges in the very first cars why should I. I prefer the natural approach of using my intuition and feelings?
    GSA: So you are saying you have no objective metrics to indicate if you are getting low on gas, and you prefer to rely on your intuition and feelings as to when you need more gas?
    CD: Yup!
    GSA: WOW… Good luck with that!

  39. moz pony Says:

    curious . . . here is a link to research on B12, the short videos are made by Dr. Greger who sources the research studies from Medical journals and pub med. I hope this helps. The recent research confirms B12 is directly responsible for floppy baby syndrome where the baby died shortly after birth and the mother was charged and went to court. How sad.. . . regards

  40. Mel Mason Says:

    Some health advocates (Mike Adams of Natural News, Matt Monarch of Raw Reform, and Gabriel Cousens from Tree Of Life) suggest that cyanocobalamin, the most common form of supplementary form of Vitamin B12, isn’t the most readily bioavailable form. They all suggest taking methylcobalamin. In fact, there are Vitamin B12 patches available by the company Healthy Habits that contain 1000mcg, as well as 400mcg of folic acid.

    Is this transdermal method more effective at getting the B12 where it needs to go, and is methylcobalamin indeed more bioavailable? At what point do we begin to split hairs over this issue?

    Thank you for your time! This is a a great thread.

  41. Jack Norris RD Says:


    Methyl vs. cyano:

    I haven’t seen research on transdermal.

  42. Maciek Says:

    First things first, you’re doing great job running this blog Jack. Up to date knowledge about nutrition stored in one place is priceless.

    Anyway, my question relates to level of absorption of the B12 taken from supplements. I’ve just read an interview with Roman Pawlak Ph.D., RD, who claims that b12 absorption from supplements is only about 1%, therefore daily dose for vegans is 240-250 μg of the b12, which is two and a half more then I can read in your Nutrient Recommendations for Vegans chart. Could you please relate to this issue?
    best regards

  43. Jack Norris RD Says:


    It actually cannot be overstated that if you take B12 in two doses a day, you’re going to be much better off than one dose. That said, I have no problem with someone taking 250 µg per day. Here is how I formulated my recommendations:

    I’m actually considering getting rid of all but the two-doses-per-day recommendations because the others are much more theoretical.

  44. Oliver Lehmann Says:

    Quote: “Half of the vegans were categorized as vitamin B12 deficient and would be expected to have a higher risk of developing clinical symptoms related to vitamin B12 deficiency.”

    Do I read this right that there is no evidence that vegans actually have developed these clinical symptoms and no evidence is available for vegans who have these symptoms, that they are caused by the persons` diets, and no evidence has shown that vegans are more likely to develop the symptoms than omnivores?

  45. Jack Norris RD Says:


    There have been many, many vegans who have developed symptoms of vitamin B12 deficiency which have been quickly and completely eliminated upon taking vitamin B12 supplements. They are reported in the medical literature on a fairly regular basis and I correspond with them on a very regular basis.

  46. Oliver Lehmann Says:


    thank you for your response.

    I always recommend to distinct between opinions, observations and scientific evidence and mark expert statements as such.

    Confusing them is a dangerous thing: E.g., almost all anthropologists support the claim that we derive from hunters. They bring this up as scientific knowledge, while it is not more than a consensus opinion which is in contradiction with unbiased observations and for which they do not have any scientific evidence at all. Hunting as an evolutionary force for our species is an unproven claim and actually not plausible at all.

    “Omnivores” (they call themselves rather meat-lovers) readily point to this claim to support their lifestyle as “natural”. I come from management, and we call this delusion “Journey to Abilene”. Another term may be consensus fallacy: The fact that experts share an opinion seems to confirm this opinion as a verified fact.


    Another common fallacy is called the “Rooster fallacy”: The rooster (in the fable) believes that his call in the morning makes the sun rise. The rooster confuses correlation with causation.

    The observation that you could help vegetarians when they exposed signs of B12 deficits is of course valid, but from a distance and without no further knowledge, it leaves many questions open: How certain was the diagnosis? How else have they changed lifestyle or habits? What metrics have you used to measure the improvements?

    Back to my original question: Is my understanding right that there is no strong scientific evidence available to support the claim that vegans/vegetarians are more common to develop B12 deficiency than meat lovers?

    The two most common arguments against a vegan/vegetarian lifestyle are hunting forefathers and B12 deficiency. As far as I can see, none of these claims is founded on rigorous scientific evidence.

    Kind regards,


    PS: I have been a strict Vegan for over 22 years. All my blood values are actually very good. If the theory of the B12 depot that may get depleted over time holds any truth, I should have started suffering from B12 deficiency more than ten years ago. Just another observation.

  47. Jack Norris RD Says:


    You are one of the rare cases. Have you had your homocysteine levels checked?

    I would recommend you read the Introduction and Background to my article Vitamin B12: Are You Getting It? It provides links to many cases of vitamin B12 deficiency in vegans.

  48. JD Mumma Says:


    I applaud you for being a vegan for over 22 years!

    1.) While it is true that non-vegans are at high risk for B12 deficiencies, I have found that the vegan community is rife with ignorance, mis-information, fallacies, magical thinking and mythology about B12 sources, needs, absorption…
    Based on my extensive research (hundreds of hours) and my 20+ years of being a vegan I currently believe the B12 issue the most serious in the vegan community.

    2.) RE: Your claim that “there is no strong scientific evidence available to support the claim that vegans/vegetarians are more common to develop B12 deficiency than meat lovers”
    There are several studies that include vegans, vegetarians and meat eaters.
    Q1: What medical studies (“scientific evidence”) have reviewed to make such a claim?
    Q2: What do you qualify as “strong” or weak scientific evidence?
    If you have not reviewed those studies then your claim might be perceived as an attempt to use the Appeal to Ignorance fallacy.
    In case you are not aware: The burden-of-proof for your claim(s) is on you and not us, and simply asking us to ‘search the web’ would not qualify as fulfilling the burden-of-proof.

    3.) “If the theory of the B12 depot that may get depleted over time holds any truth, I should have started suffering from B12 deficiency more than ten years ago.”
    A.) If you are using the term “theory” as it is applied in science, then a theory is an accepted hypothesis (
    B.) A theory is typically not made invalid only on the basis of one anecdotal testimonial (e.g. your personal story).
    C.) While anecdotal and testimonial data can be valuable and important, it can also be very inconsistent and unreliable compared to statistically significant data collection which is usually a primary element in high level medical science studies.
    D.) There are numerous sources of B12 so a proper evaluation would need to be conducted to determine that you have zero intake of B12.
    E.) You have not yet provided any objective medical science information to verify your claim that you are not “B12 deficiency” Therefore we currently can not confirm that you do not have a B12 deficiency.
    If you are using subjective information to determine whether you are B12 deficient please keep in mind that “The neurological manifestation well precede the hematologic manifestations.” Sally Pacholok, RN (Emergency medicine) co-author of Could it be B12?

  49. Oliver Lehmann Says:


    of course I am rare case. I am a business trainer, and when my students see me in classical business attire, the the giggest surprise for them is that I am a vegan by conviction. I am not sure that I can be role model to others, but I do my best.

    My homocysteine levels are OK, but I commonly come up with doubt when others have quick answers at hand. I do not believe in quick answers, at least not in business and in health matters.


    I do not make any claims at all.

    I strictly separate opinions, observations and claims and mark my statements as such. I ask questions. I think that this is an essential element of rigorous thinking.

    You are correct in stating that there are numerous sources of B12. So, the simple equation Vegan = B12 deficiency disease may be questionable.

    I am pretty sure that I do not have B12 deficiency because:

    – I do not show any of the symptoms described in literature (e.g. lack of energy)
    – I have been blood-tested last month. My Doctor is very impressed of my blood values that are much better than normal for a man at 55.

    But I agree, this is not scientific, but anecdotal. Just as Jack’s observations, that he reported, and to which I answered with my PS.


    I started researching the topic recently because my wife, who is not a vegan, not even a vegetarian, was approached by her family, all hunters, saying that I am in big danger and that she needs to convince me to eat meat. They are always so afraid of my health, especially when TV sends out warnings.

    So, what do we really know?

    Pawlak e.a. (2013) made a literature review on 18 articles and found strong and repeatable statistical evidence for low serum levels of MMA in Vegetarians and Vegans. They do not provide evidence that this had an impact on the health of persons.

    Hermann e.a. (2009) measured B12 deficiencies in serums from Vegans and Vegetarians compared to omnivores, but found no related clinical symptoms in them (p. 1384).

    Hermann e.a. (2003, cited in Pawlak e.a.) report that Vegetarians who take B12 supplements have a lower rate of B12 serum deficiency than those not taking supplements, but Vegans who take B12 supplements, have an even higher rate of serum deficiencies. They also do not report any clinical symptoms of the deficiency.

    Gilsing e.a. (2012, pp. 936, 938) did not find increased serum levels of B12 in users of B12 supplements, compared with non-users.

    Gilsing e.a. further found that there is no link between the time that a person has been Vegetarian or Vegan and the B12 levels, which contradicts the theory that there is a B12 cache that may be depleted due to long-term Veganism or Vegetarianism, and that deficiency symptoms may come late after the beginning of the deficiency phase. They assume that there may be “…mechanisms that maintain circulating concentrations of vitamin B12 [that] are upregulated in vegetarians and vegans.”

    If one looks at the inconsistency of scientific evidence on Vitamin B12, one must clearly say that the case of B12 for Vegans and Vegetarians has not been fully understood yet.

    Kind regards,




    Gilsing, A, Crowe, F, Lloyd-Wright, Z, Sanders, T, Appleby, P, Allen, N, & Key, T 2010, ‘Serum concentrations of vitamin B12 and folate in British male omnivores, vegetarians and vegans: results from a cross-sectional analysis of the EPIC-Oxford cohort study’, European Journal Of Clinical Nutrition, 64, 9, pp. 933-939, viewed 11 September 2013.

    Herrmann, W, Obeid, R, Schorr, H, Hübner, U, Geisel, J, Sand-Hill, M, Ali, N, & Herrmann, M 2009, ‘Enhanced bone metabolism in vegetarians – the role of vitamin B12 deficiency’, Clinical Chemistry & Laboratory Medicine, 47, 11, pp. 1381-1387, viewed 11 September 2013.

    Pawlak, R, Parrott, S, Raj, S, Cullum-Dugan, D, & Lucus, D 2013, ‘How prevalent is vitamin B(12) deficiency among vegetarians?’, Nutrition Reviews, 71, 2, pp. 110-117, MEDLINE with Full Text, viewed 11 September 2013.

  50. Jack Norris RD Says:


    Did you read the link to the article I recommended to you? Here is another page that you should be aware of:

    There is an easy explanation as to why cross-sectional studies on current vegans do not show many of them to be suffering from overt vitamin B12 deficiency — because once symptoms start to appear, they seek medical help and either start taking vitamin B12 or quit being vegan. That said, you will see at the link above, and also in one of the first studies of vegans here…

    …that some studies have found some vegans to be suffering symptoms of overt B12 deficiency. And the anecdotal evidence is overwhelming.

    Vegans do not need to eat meat (or dairy), they can take vitamin B12 supplements or eat fortified foods as many thousands of vegans currently do.

    You may be the exception for now, but for how long? Don’t end up like this guy:

    80 Year Old Vegan Not Supplementing with B12 Develops Nerve Damage

    Bernstein (2000, USA) describes a man in his eighties who had been in excellent health, and was a runner. He had been vegan for 38 years and attributed his ability to outperform younger people to his diet. In the span of a few weeks, mental disturbances began to set in. He cried, was confused, got lost, was incontinent, lost control of his bowels, and lost motor skills to the point where he could barely stand with help. He was diagnosed with “senile dementia.” A blood test showed slightly large red blood cells. Further blood tests revealed that his B12 level was undetectable. He was given an injection of 1000 µg of B12. The next morning he could sit without help. His bladder control returned within 48 hours. By the end of the week, he could play simple card games, read get-well cards, and talk on the phone. He still cried easily and his attention span was too short to go back to work. Bernstein concludes, “[A] diet free of animal protein can be healthful and safe, but it should be supplemented periodically with vitamin B12.”

    Reference: Bernstein, L. Dementia without a cause. Discover. February 2000:31.

  51. Adrienne Says:

    Hello, this is a great thread, but it honestly made me a little scared. I have been a vegan for over ten years and I was a vegetarian for over 5 years before that (I’m 29 now so more than half of my life). My whole life, my mother always had us take multivitamins daily and I take specific vegan vitamins now. I’m just very concerned because I have been vegetarian/vegan for so long without being aware of proper vitamin intake. If I have not consumed enough B12 for all of these years, would the damage be irreversible? After how many years does B12 deficiency begin to show symptoms? Could the multivitamins that I took growing up have been enough to prevent me from having deficiency problems? Thank you.

  52. Jack Norris RD Says:


    > After how many years does B12 deficiency begin to show symptoms?

    It depends on the person. I wouldn’t worry about it, just make sure you have a good source from here on out. And since I don’t know how much B12 is in your vegan vitamin, it’s possible you’ve already had a good source for most or all of your life. Did you drink fortified soymilk or other fortified foods?

  53. Adrienne Says:

    Thank you. Yes I used to drink a lot of soy milk when I was younger. I checked and both kinds that I drank have B12 in the ingredients online. Thank you, I was just worried after reading everything!

  54. JD Mumma Says:

    B12 is definitely a nutrient to not guess about or rely on subjective feelings (e.g. when people say things like “I feel fine. I must have enough B12”).
    The best (most accurate) way to know for sure if your body has enough B12 is to have simple objective medical test. One test known to be a very accurate (far more accurate than a standard B12 blood test) indicator accurate, as well as being the simplest (uses urine instead of having to draw blood) as well as a low cost ($50-100) is to have your MMA (methylmalonic acid) level checked.
    Wishing you continued success on your vegan diet.

  55. Jack Norris RD Says:

    JD Mumma,

    I would only suggest that someone get their MMA levels tested if they suspect that they might have B12 metabolism problems. See here for getting B12 status tested:

  56. Andrius Says:

    I don’t understand one thing. If there is a store of B12 in a human’s organizm that is enough for several years (some sources state that B12 deficiency begins several years after a person stops consuming food with B12), then why are there recommended DAILY doses that have to be taken continuously? If I have a full fuel tank, I drive a car to work and not fill it up every day – I only have to do it when I see that the fuel level is low. If a person has enough of B12 for several years in them, that means they could live, let’s say, a year without worrying about taking B12 supplements, then fill up their B12 store by taking B12 supplements for some time (a month, for example) and then live without worrying about it for another year and repeat everything? That is much easier than taking pills every second day. I mean, is it possible to do so? If not, then how does that store of B12 work?

  57. Jack Norris RD Says:


    2 things to consider:

    1. Almost no one has enough vitamin B12 stored to prevent the sublinical deficiency associated with elevated homocysteine levels and dementia for very long without a supply of B12.

    2. The way B12 works, from what I can tell from reading the research, is that only a certain amount of the B12 in your blood can be transported to your tissues, and that B12 has to enter the system through the digestive tract. There are two ways B12 gets into your digestive tract: a) the liver excretes it into the digestive tract, b) you eat it. As B12 stores dwindle, less and less B12 gets secreted into your digestive tract by your liver. Once those stores are fairly well depleted, it would take an enormous amount of B12 to build them back up so that you could again rely on what’s secreted into your digestive tract.

    If you are not concerned about #1 above, then you could just rely on building your stores up and then using them for a period of time without supplementation. But how would you even know when you have built up your stores and when you haven’t? It’s not a reliable way to go.

  58. veganlass Says:

    This is an informative blog. One thing I don’t understand though is this. Peta and other sites I’ve been reading say that veganism is the natural diet for a human. That we are absolutely herbivores. I have believed this to be true with my reading but now think maybe it can’t be. If we were indeed natural herbivores then we wouldn’t need to supplement – would we? Cows and other herbivores don’t need to supplement with any particular vitamin so the fact we cannot get all our vitamins from our diet if we cut out animal products means categorically we are not natural herbivores?

    This is then a dangerous myth that makes vegans believe we don’t need supplements as we are eating the optimum ‘natural’ diet for humans. A lot of my meat eating friends have also laughed at me when I’ve tried to say we are natural herbivores and now I am beginning to think there is a lot of misinformation out there on some vegan sites. I will start to supplement straight away with B12

  59. Jack Norris RD Says:


    This should answer your question, I hope:

    Cows and other ruminant mammals (though not all herbivores) are much different from humans. They have multi-chambered stomachs which allow significantly more bacterial fermentation than do our digestive tracts.

  60. Dee Says:

    Jack, can you please recommend a trustworthy resource re: supplements for my 6-month old vegan baby? I have your book – I don’t see it in there. I’m giving her vit D daily, but I wonder if I should be giving her b12 and iron.

  61. Jack Norris RD Says:


    On p. 146, we give the amounts for a child your daughter’s age in the table. I cannot find a vegan multivitamin that has iron, vitamin D, and B12 in those amounts, so I would suggest just getting each nutrient separately. She only needs iron if she isn’t getting enough from her diet (such as if she is still being primarily breast fed). You can give her a lot more B12 than what we suggest, it might be easiest to give her 250 mcg twice per week by buying 500 mcg or 1,000 mcg B12 tablets and breaking them into quarters or halves. If she’s getting B12 fortified foods twice a day, then she shouldn’t need a B12 supplement.

  62. melissa Says:

    B12 is synthesized in the intestines. You can’t just take it. Hence it’s a myth. I checked my b12 levels when going vegan 10 years ago, and again this year. I’m not deficient. I’ve never taken supplements. It’s a lie.

  63. Jack Norris RD Says:


    If what you’re saying is true, then you’re lucky. You should read this page at VeganHealth:

  64. matt Says:

    I have researched this topic with at least some diligence. In that research I have found the percentage of vegans and non vegans with b12 deficiency is nearly identical. My findings in regards to an explanation are those indicating individuals with the deficiency are ignorant of being infected with a parasite. I haven’t done any follow up research in a few years. I have been vegan for 5 years now and get periodic blood work dome to make sure my vitamin levels are okay. I also make sure to do periodic detoxes for parasites. I have no b12 deficient problems.

  65. Jack Norris RD Says:


    I’m not sure how someone could read my post above and then respond with a comment such as yours. My response to your comment is, “Please read the post above.”

  66. Hanna Says:

    I’ve been reading the reccommendations and absorption rate tables for b12 on your site. The multivitamin I take contains 15 mcg b12 and looking at the absorption rates I’m guessing ~1-1,5 mcg gets absorbed, which wouldn’t be enough, especially being mostly lacto-ovo vegetarian since birth with only a few periods of eating small amounts of meat. Looking at fortified plant milks, the ones sold locally contain 0,38 mcg/dl so to get somewhere close to enough, even with the higher absorption rates would seem to require drinking something like 6-7dl/day, which seems daunting and would get very expensive.

    The smallest supplements I’ve found so far are 100 mcg. Would half a 100 mcg tablet once a day work in combination with the multivitamin (15 mcg) if not taken at the same time or could there be issues I’m not aware of?

  67. Jack Norris RD Says:


    100 µg per day is all you need. If you take it at the same time as the multivitamin, then the extra 15 µg won’t add much, but it won’t hurt either.

  68. Jonathan Says:

    I find it odd that people still are going on about the B-12 issue, I have been vegan for almost 15 years and I do not take supplements for it, however I do have a healthy diet of vegan food and products that make sure I get everything I need.

    I have many friends that are vegan and they have friends that are as well, no one have problem with the lack of B-12, so it seems that people who do have problem with it doesn’t eat enough of what they need to be eating or that they are eating way to little over all.

    I check my self every 2 or so years, and my doctors always tell me the same thing and that is that I am as healthy as ever.

  69. Jack Norris RD Says:


    If what you’re saying is true, and you do not eat B12-fortified foods, then you are lucky and your luck might not last forever.

    You should read this page:

    > it seems that people who do have problem with it doesn’t eat enough of what they need to be eating or that they are eating way to little over all.

    So if a vegan gets vitamin B12 deficiency, your advice would be to just eat more of what you need to eat?

  70. JD Mumma Says:


    Re: ” I do not take supplements”
    If you are eating packages/processed food then there is a very high probability that B12 has been added (it will say so on the label) which means that while you may not be taking a separate B12 supplement, but if you are eating foods that have B12 added as a supplement then you are technically supplementing with B12.

    Many people have their doctor check their B12. The problem is that most doctors are uneducated about B12 and are still using the standard serum (blood) B12 test that is know to sometime have false positive or false-negative readings. A very simple and non-invasive (no venipuncture/needle) is an MMA test which is available as urine or serum (blood) test.

  71. Melissa Says:

    I am still in need of a bit of convincing that this B12 man-made supplement is actually necessary. Doesn’t nature provide us with everything we need already? I’m sure there are many who would agree with me – that they have purchased expensive high-quality supplements and protein shakes and have never felt a difference. All the organic supplements and powders were a huge waste of money. Why should I believe that I need vitamin D and B12 pills to keep from becoming deficient and sick? Fortified cereal? All the fortified cereals that I’ve seen are loaded with lots of crappy ingredients – including sugar. I don’t buy processed food. I buy fruits, nuts and vegetables. I’ve been doing it for years and I feel very healthy. My blood and urine tests show that I’m healthy. I am not convinced. I’m a skeptic of everything and I ask lots of questions and do as much research as I can. I enjoy learning, but I don’t enjoy being taken advantage of. I’ve also learned that cyanocobalamin is not healthy to be putting in our bodies. I learned about this years ago. Thank you for your time and for any answers you can provide me with. I would love to know if vitamin D and B12 supplements are absolutely necessary to take.

  72. Jack Norris RD Says:

    Hi Melissa,

    Since you are skeptical of everything, you might want to add these to the list:

    > Doesn’t nature provide us with everything we need already?
    > I’ve also learned that cyanocobalamin is not healthy to be putting in our bodies.

    This article and links in it explain why vegans should get a reliable source of vitamin B12:

    If you read that, which is admittedly a lot, and you are still not convinced, then I have nothing more to add except to wish you good luck on your path.

    As for vitamin D, you can get that from sunshine on your skin. If your vitamin D levels are good, you get plenty of daytime sun, and you don’t supplement, then I see no reason to start. Here is more info on that:


  73. Dave B. Says:

    Not sure I agree with your post. She made some very accurate claims. You do bring up a couple of points. But, I’d rather ask about my own. Since we know that the microbes in the gut are located in the epithelium all throughout the small intestine, far above the ileum, there is every reason to believe that if the microbes thrive they will synthesize b12, once again far above the ileum where we can absorb them. Your thoughts?

  74. Jack Norris RD Says:

    > there is every reason to believe that if the microbes thrive they will synthesize b12, once again far above the ileum where we can absorb them. Your thoughts?

    Most microbes don’t produce vitamin B12 and given the prevalence of vitamin B12 deficiency among vegans in western countries who don’t supplement, it would be unwise to rely on your intestinal bacteria for B12.

    > This is why the percentage of meat eaters, sometimes heavy meat eaters , have b12 deficiency is just as high as vegetarian or vegan do.

    Vegans who do not supplement with B12 or eat B12-fortified foods get vitamin B12 deficiency at a much greater rate than non-vegans.

  75. Dave B. Says:

    And we do know that it is very accurate to claim that b12 deficiency really comes down to absorption issues, not nearly as much by the amount that we consume. We also need to look at the health of the parietal cells in the stomach, the rate of secretion of hydrochloric acid, containing intrinsic factor. Because of course we know that we need intrinsic factor to bind with the b12 for it to be able to be absorbed in the gut. This is where most people get b12 deficiency, not because they’re consuming too little. This is why the percentage of meat eaters, sometimes heavy meat eaters , have b12 deficiency is just as high as vegetarian or vegan do.

  76. Human Says:

    So I have a question. I know this guy who has been vegan for awhile. He claimed that he got tested and doesn’t have a B12 deficiency. He doesn’t take supplements and he claims that he doesn’t eat fortified foods. How is this even possible??? I thought sufficient B12 could only be found in animal products and fortified foods.

  77. Jack Norris RD Says:


    Overt B12 deficiency can be warded off for many years due to the body’s ability to hold onto critical amounts of B12. Usually vegans who don’t show symptoms have elevated homocysteine levels–an early indicator of B12 deficiency. There are some other explanations–he could be one of the rare people who have B12-producing bacteria in his small intestines or perhaps gets it through B12-producing bacterial contamination of foods he regularly eats. If he lives in a developed country, the most likely explanation is that his body conserves B12 very efficiently but that he’s on his way to a B12 deficiency.

  78. HeyMan Says:

    Okay so I have a question.

    Is it scientifically agreed upon that Vitamin B12 is indeed synthesized in our small intestine? However, the reason why we don’t absorb it is because the same place it’s synthesized is the same place “already active B12” gets absorbed? Therefore – there is simply not enough time for the B12 we synthesize to get absorbed.

    If this is the case, then coprophagia (which is completely healthy if you’re not infected with any illnesses, keep that in mind) would be a natural way of getting B12. Non-ruminant herbivores like rabbit do it. Other homindae like Gorillas and Apes are known to do it as well, although they are also known to eat insects. Anyway… my point is in theory – and I’m not saying you do this so don’t throw a red herring argument my way – you could get B12 eating your own shit.

    Your take on this? Done enough research on this? I’m interested to know what your thoughts are.

  79. Jack Norris RD Says:


    B12 is produced by bacteria in the colon. It is unclear whether it has too much inactive vitamin B12 analogue to prevent it from improving B12 status.

  80. Lew Stewal Says:

    In reply to Heyman’s 2-year old post, I found this site referenced while reading about B12 on the site. In fact, there is scientific reference on the NF site to a study of B12 deficient persons that agreed to have their feces encapsulated in pill form in order to treat their B12 deficiency. Yes, their B12 levels rose after swallowing their own feces. The point is, _your_ point in theory has been proven to be true.
    It seems B12 in the lower intestine is not absorbed well enough to be useful for most people.

  81. Sylvie Says:

    I was confused about all the contradicting information, so I decided I would find out. I have been a strict vegan for one year and a half, then got tested for B12. Well, I had a B12 deficiency! So I started eating meat again, no B12 supplement, and my B12 became normal again. When I was a vegan, I tried to eat very healthy, red star yeast, all the things that are supposed to help. My thought was, if we are supposed to be vegan, we should not have a deficiency in B12. And I read that in some countries, they are vegan. But later I found out that those vegan people often eat insects. I don’t know if this is the case everywhere in the people that are vegan, but this would be a good explanation why they don’t lack the B12 vitamin. I started to be vegan again a few months ago, and I take both methyl and cyan.. because of the différences of opinion about which is best. One day I take one kind, the next day I take the other kind. I know of two different people who got excellent results with methylcobalamin, they lacked this vitamin before, and were ok after. And since research is more about cyanocobalamin, then I take it too. Maybe some people are ok with taking no supplement, but it does not mean that all people will be ok. I got the proof that being vegan was the reason why I lacked the vitamin since it was back to normal when I ate meat again.

  82. Martha Says:

    My husband became vegan and in about 4 yrs. developed a serious B-12 deficiency with sores in his mouth and tingling in his feet. He hadn’t been told that he should supplement with B-12 as a vegan. When he went to a walk-in clinic for his mouth sores he was dismissively misdiagnosed with gingivitis and told to go brush his teeth. Thankfully shortly thereafter we had access to a MD who understood veganism and suspected a B12 deficiency, tested him for it and prescribed 1st B12 shots followed by oral B12 supplements which he has taken faithfully. We found out just in time to prevent permanent damage.

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