Doctor's Note

I make a similar “baggage” argument about meat in my video Food Is a Package Deal, and about dairy in Plant vs. Cow Calcium. Next, I’m going to get into the nitty-gritty on how much one needs on a weekly basis, in Cheapest Source of Vitamin B12. And then I’ll cover daily dosing in Daily Source of Vitamin B12. Or, you can skip to Vitamin B12: How Much, How Often?

And for background, see my blog post: Vegan B12 Deficiency: Putting It into Perspective. For more on how many eggs would be required for other nutrients, see Egg Industry Blind Spot. And those with a thing for vegan bowel movement studies, see Bristol Stool ScaleBowels of the EarthFood Mass Transit; and Bowel Movement Frequency

For more context, check out my associated blog posts: How to Enhance Mineral AbsorptionPreventing and Treating Kidney Failure With DietStool Size and Breast Cancer Risk; and What Is the Healthiest Meat?

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  • Michael Greger M.D.

    I make a similar “baggage” argument about meat in my video Food Is a Package Deal and about dairy in Plant vs. Cow Calcium. Tomorrow I’m going to get into the nitty-gritty on how much one needs on a weekly basis, and Wednesday’s video-of-the-day will cover daily dosing. Or you can skip to Vitamin B12: How Much, How Often? and for background, see my blog post Vegan B12 Deficiency: Putting It into Perspective. For more on how many eggs would be required for other nutrients, see Egg Industry Blind Spot. And those with a thing for vegan bowel movement studies, see Bristol Stool Scale, Bowels of the Earth, Food Mass Transit, and Bowel Movement Frequency. And there are videos on a thousand or so other topics so please feel free to dig in!

  • Please make this and ALL videos available on your YouTube homepage!!

  • Thea

    It may be a character flaw, but I have to say that I will never be that hard core.

  • BPCveg

    Is there any risk of toxicity associated with high intakes of vitamin B12?

    • Toxins

      No, it is water soluble so it easily exits our system. Similarly, vitamin c is water soluble. You can take way over the recommendations and be perfectly fine.

      • elsie blanche

        What is the long-term data on this, and how are we to know that the immune system is not somehow being “freaked out” by this immediate intake of such large amounts of B12, even prior to ingestion? I’ve had horrible reactions to B12 supplements at times (have experiment with all the different forms, amounts, and methods of intake) and I know others who have had horrific experiences with B12 supplements as well. Some to the point of near heart-attack symptoms. I and others would like to make the B12 thing work great, but the reality is is that for some it makes things far worse. (A theory of mine is that some people with SIBO or borderline SIBO issues end up “feeding” their SIBO bacteria to be even “stronger”. But I do believe there are many other factors at play in causing some people to dread ever having to take B12 in supplement form, after experience the scary reactions.

        • Seth Grimmr

          Are you sure you friends and yourself aren’t just finding yourselves caught in a web of hypochondria? If not, did you consider a smaller dosage? You do not have to eat a 2500 mcg supplement. You can take a daily supplement. Also, how often did you take it and what mcg level was it? These are all very important factors to your anecdote. I have actually heard of someone who broke out after beginning to supplement with B12. The breakouts stopped as soon as she quit taking them as frequently. One last thing, have you been checked for a potential allergy to anything in the supplements aside from the B12 itself?

          • elsie blanche

            Seth, thank you for inquiring and your words. I’ve checked all bases, it seems. And bloodwork has
            been done as well. Frustrating. I treat this like science, to the best of my ability. I’m in no way the only
            one out there who can not tolerate B12 supplements in any way shape or form. It is what it is for now.
            But if you come across a legitimate source of completely natural vegan B12 (not man made/lab factory
            produced) , please let me know.

      • sabina

        Some people reported having got acne because they took too much (the amount of a month, every day! They didn’t read the package!)

  • Mark Biddy

    What if we were to fast for 24 hours every other day, I wonder of the body would be forced to absorb it’s homegrown B12.

    • Toxins

      We do in fact produce b12, but it is too low in our intestines to be absorbed. Our stools do contain b12 though.

  • tduke

    Dr. Greger what is your official recommendation for B12? how much, how often and what kind?

    Thank you!

    • Toxins

      the answer is 250 mcg per day or 2500 per week minimum.

      • Guest

        no,it was 1000mg per 10 days..? and the link you give doesnt work…

    • Michael Greger M.D.
      • Sasho

        Unfortunately, that link doesn’t work anymore.
        Can we please get an update on this?

        Thanks! :)

        • Coleen

          Click on the one in the doctors note up there then

  • nsd

    I’m sure this question has been asked before, but it sounds like you can’t be healthy vegan without taking supplements. Is this really a healthy diet then? Shouldn’t we as humans be able to thrive on whole foods alone? I really enjoy your educational videos, Dr. Greger, but I struggle with the idea that we are designed to use supplements. I would love to hear your thoughts on this topic. Thanks!

    • Toxins

      Vitamin B12 is a byproduct of bacteria, it was once found in our water supply, and on the plant foods we eat. Because we now chlorinate our water (to avoid getting sick from other bugs) and because we dont ground pick our vegetables from the wild without washing them, the only available source is now from animal products. This is of course an unnatural setting. Similarly, iodine is no longer found in plant foods. This is why the government iodized salt, to help Americans get adequate iodine intake. Similarly still, we do not expose ourselves to adequate sunlight, and the UV rays of today are much more potent then they once were in our evolutionary past so vitamin D must be supplemented for optimal health.

      Humans have changed their environment, so sometimes supplements are necessary to achieve optimal health.

      • Thea

        Toxins: For some reason, I didn’t see your reply on screen and it didn’t come to my e-mail account until hours after I had written my reply. Your reply is so good, I would not have bothered if I had seen yours first.

        • Toxins

          Thanks for the compliment and no problem, your reply below is pretty good too!

          • morph2020

            Regarding toxins, or is it Toxins, are you all aware that absolutely everything is a toxin if you have too much of it too fast? Google the term “water intoxication,” for example.

    • Thea

      nsd: This is a good question and one that gets asked often. Dr. Greger may have an answer for you, but I wanted to share my thoughts too.

      I’m aware of two main supplements which Dr. Greger recommends, and they both make sense. Vitamin D is recommended for everyone, whether vegan or not, because we are no longer running around naked at the equator. It doesn’t really have that much to do with your diet.

      Vitamin B12 is needed because our modern society has artificially cleaned up bacteria in water and soil. The cleaning up of the bacteria is generally a good thing since we then avoid the bad bacteria. The problem is that with steralized water and soil, we then loose the good by-product of some bacteria, i.e.: B12. So, where do you get your B12? Well, you could get it from animal products, but that is frought with danger since whole foods are package deals. (See the multitue of videos on this site about the likely cancer and other disease promoting properties of animal products.) Or you can get your B12 from a safe and inexpensive supplement.

      Modern humans no longer live in our native habitat – the environment that we evolved in. Thus it makes perfect sense that finding the healthiest way to live would require adjustments.

      I strongly encourage you to check out the following links from this site. The video shows typical vitamin deficiences (that we know about) in average vegans vs omnivores. I think this is the perfect answer to your question. What is the easiest way to eat healthy? Whole plant foods – supplemented when needed to accommodate our unnatural modern life.
      also check out this blog post where I think that Dr. Greger has at least partially answered your question more directly:

    • I’ve never had B12 issues, even though I’ve always had a low dietary B12 intake, even when I was a lacto-ovo. I do eat fortified cereals every once in a while, though. About 95% of my food is organic and wild.

      Here’s my post about B12!

      Many of us will never get B12 deficiency. Most of those that get B12 deficiency have absorption problems, which can be caused by many factors, including wrong diets, conditions like pernicious anemia, damaged gut, antibiotics and meds, etc.

      A human that lives a healthy lifestyle and eats a normal diet, does not get B12 deficincy. But most people live in an unnatural environment and eat wrong diets that are high in protein and fat, so it shouldn’t be surprising that they are at high risk of getting deficiencies.

      • beccadoggie10

        I’ve read from research gathered by Jeffrey Smith that Vitamin B-12 is now genetically engineered (recombinant DNA). And, I’ve noticed with most vitamins, that B-12, along with Vitamins C and E no longer work as supplements. So, I look for food sources, like sunflower seeds for vitamin E, a variety of raw fruits and veggies for vitamin C, and miso (not heated to high temperatures in cooking) for vitamin B-12.

        I do not want to eat GMO’s in fortified breakfast cereals, especially those where the owners of the companies have funded the Right to NOT know about GMO’s in Foods (and pharmaceuticals).

        • morph2020

          You are already eating GMOs. Fortified foods have vitamins and minerals added. For example, common table salt is “iodized” to protect you from goiter. Some types of foods have folic acid added to them to help prevent spina bifida and related birth defects. Fortification just means a nutrition supplement has been added. We now have GMO potatoes that make a small amount of a precursor to Vitamin A inside the potato. This helps prevent blindness in many third-world countries.

          Nature is not inherently kind to us. That is why we have science. The ultimate purpose of science is to increase human longevity and comfort and give us enough control of our circumstances as to become like God.

      • morph2020

        Pernicious anemia is not impossible; it’s just rare.

    • You can’t be serious

      Yeah let’s ignore all the diseases that people suffer from as a direct result of consuming animal products (people who consume animal products take supplements, too by the way) and declare that eating according to the way our bodies were designed must not be healthy simply because we gotta take one tiny pill a day because WE ruined our environment that used to provide us with B-12 by natural means. Good one!

      • morph2020

        You are surely educated enough to know that “natural” things are no safer than “synthetic” things. If all of the “natural” things are safe, then try a little “natural” poison ivy, or “natural” snake venom. If nature is so benign, try camping out. From the moment we are born, nature starts trying to kill us and recycle us. In the old days before modernity, nature was more successful at recycling us before our first birthday.

    • morph2020

      Vegetarianism is an unnatural diet. When Benjamin Franklin went on one of his first Atlantic crossings, he had been experimenting with vegetarianism. One of the crew on his boat decided to cast a line and see if he could catch fish. The fishing was good, so the ship served fish that night Franklin had observed the cutting open of the fish and was shocked to see that their internals were filled with smaller fish. Franklin declared that, “if you can eat your smaller brothers, then I can eat you.” He gave up vegetarianism on the spot.

      • Ogz

        I … I….don’t even know, where to start with this reply….

  • Meha

    A Brazilian Portuguese version:

    • Michael Greger M.D.


  • ElaineV

    Love the “those are some hardcore vegans” comment :D

  • CV Dr. Sheila Callender, MD, D.Sc, FRCP

  • Jean Leduc

    A friend recently told me that the B12 I was taking as a supplement for vegan was a poor choice. I take tablet of cyanocobalamin with a meal and daily fortified soy milk and cereals. According to my friend, the superior way of getting B12 is with sublingual tablets. A quick research on the Net gave me 4 ways to get B12: injections, nasal spray, sublingual and swallowable tablets. All the sites claim to have the best product without citing any verifiable studies. AND they all happen to sell it… Is there a comparative study on the topic.

    • CloudTiger

      Forget studies. The cyanocobalamin is the WORST B12 to take.. it is not “natural” and is actually antagonistic to good B12, hydro or methyl. I would bin it and do my research before I bought next time. The consensus of those not selling out (to cheap cyanocobalamin and high profits) is methyl is best. Sublingual seems nicer than hypo injections but if I was seriously deficient I would not mess about. Straight to the net to buy methlyl jabs in high doses.

  • wchiwink

    being a vegetarian, (still eat sardines, mackerel, anchovies) i have been concerned with getting enough B12 – eat Marmite every morning, which is supplemented with it 0.6 % RDA for 4 grams…which brands for B12 supp. are best ?

    • Toxins

      Here are Dr. Greger’s recommendations for b12

      as well as the video series on b12

      I would also strongly advise you to cut out all fish consumption because fish is the most polluted animal product one can consume. Although true that the fish you are eating are lower in contaminants then most others, you are sitll exposing your body to envoronmental toxins that will build up over time and can cause neurological and hormonal problems.

  • WholeFoodChomper

    The image of the cow with the bacteria graphic that comes flying out of the cow’s nether regions has me laughing every time.  Love it!

  • Kathimecs

    Are there 2 types of B12? I have heard that the one type is not readily absorbed but the methylcobalamin is in a form that is readily absorbed. Is this true? Most of the the OTC suppliments contain the other form of the cobalamin. Is it worth taking these?

  • Alfred

    Is the below comment true?

    “This argument is still hanging around, however, according to Dr Vetrano it was disproved by research over 20 years ago and is nothing more than an obsolete scientific theory.  Indeed, in a 1999 version of ‘Human Anatomy and Physiology’ by Marieb, it states quite clearly that we do indeed absorb vitamin B12 through our intestines.” (

    • Dan

      Vetrano also claims that smallpox isn’t contagious. Stay away from the psudo- science quacks. B12 deficiency isn’t something to take a gamble on.

  • Wchiwink

    Yes, i too would like to know what type of B12 supp. to take….i just bought a “cyanocobalamine” one…is this good?
    (i did just end up in the hospital for a huge acute allergic reaction to something i ate or did recently….!)

  • Mel

    Hi, Im surprised no one mentioned nutritional yeast here?  I LOVE that stuff I use it most days in soups, on pasta etc.  As far as I am aware it is the only naturally occurring b12 food source that is also bio-available ( I believe that Dulce also contains b12 but it isnt bio-available due to chelation?)  Please feel free to correct me if I am wrong. :)  Thanks again for a great channel!

    • Lisa

      actually, nutritional yeast does not naturally have B12, only the fortified kind.

  • Worth noting that pretty much any fortified food is processed and not really a whole food. Better as a supplement.

  • Dada

    what about b12 shots?

  • I read this:

    Can you be sure the body will not make enough B12 it’s self? Can you show me science that proves we can’t absorb the B12 in our intestines? Thanks

    • Dan

      I hope you realize that most, if not all, the people sited in that article are not credible sources in either the medical or scientific community. While they may be popular in raw food circles, they practice psufo-science and their ideas border on dangerous. If you want to develop b12 deficiency because you listened to Doug Graham, go ahead.

      • Doug Graham has a Ph.D, and is well respected. It’s not pseudo-science. Helps if you know how to spell pseudo. I have read what many people have said about B12, from Dr. McDougall to pretty much every vegan nutritionist and doctor that is well known. And a lot have said that it depends on the person. And most people only get B12 problems in there 50s. When the body starts to break down. So I asked for evidence to show why B12 is not absorbed by the intestines. As for some people it is. Some it isn’t. It depends on the person as far as I am aware. If people take B12 all the time we wont evolve to make our own B12. So do what you think.

        • Y.A

          it has shown to be too far down to be absorbed

          • Stephen Lucker Kelly

            Sorry I made a mistake, actually I was miss lead Doug has something similar to a Ph.D, but doesn’t actually have a relevant qualification to nutrition, but that doesn’t however disregard what he says. However lately I don’t agree with him on some topics, but some of what he says does make sense and is correct. He does have a lot of experience training athletes, so it’s not fair to disregard what he says just because he doesn’t have a Ph.D when he has a lot of experience. But Mistakes happen. I am human I make mistakes occasionally. This was 3 years ago. Please check the date.

            However what I said isn’t far from the truth, the body can adapt and some people have adapted to make their own B12 with out the need of supplements but that is rare. It is safer to take B12, but makes more sense to track b12 levels and make sure the levels of B12 don’t get too low. If they’re too low than it would be safer to take a B12 supplement. But it really depends on your body don’t assume that people are like you in studies, it’s best to work out how your body works. And it is possible to get the body to make more B12 than usually but it means eating higher amounts of nutritious food, and creating more bacteria.

            I could go on, but the above message was meant to be about keeping an open mind.

          • Gary Loewenthal

            Some thoughts:

            – The consistency of these studies should be taken to heart: In study after study, vegans’ average b12 levels are lower than that of non-vegans, it gets lower over time, but normalizes with supplementation.

            – It’s true that there’s variation, and you may be on the high end of the bell curve. But why take a chance. At least get MMA and homocysteine levels checked, as measure of whether your body has enough usable b12.

            – Once you’re low in b12, you may already be putting yourself at risk. Prevention through a supplement is safe, easy, and fairly cheap.

          • morph2020

            The body has only a limited capacity to adapt. If you stress one of us enough by taking away enough of a vital nutrient, we will die. Our offspring might have hope of being more functional in such a stressed environment. Everything seems to have an acceptable level of concentration, but too much will become deadly. Too much of ordinary carbon-based food will kill any of us with gross morbid obesity, what I call simply “carbon poisoning.” It seems realistic that, if you drank a half-gallon of olive oil every morning, you would eventually exceed some sort of threshold and die from it. It would be likewise for anything else considered to be a “health food.” Too much of a good thing is not, as Mae West said, “wonderful.” Too much of a good thing is a bad thing. Be moderate in all things. You should even be moderate about moderation. Maybe Barry Goldwater was right. “Moderation in the pursuit of liberty is no virtue.”

        • morph2020

          Well, I also have a PhD. Having one doesn’t mean you know everything. It helps to have some data, if not a little humility, too.

  • Tracie

    What about nutritional yeast?

  • What about sauerkraut? What is the B12 content of sauerkraut?

    • I never see any mention of sauerkraut in B12 discussions. But sauerkraut is full if bacteria that are known to produce B12. So surely it is an excellent source. And could potentially remove the need for supplements.

  • Fidel Castrati

    Even Dr. Greger admits cyanocobalmin is not THE safest form of b12 for EVERYONE, and that’s the kind included in fortified foods and the cheaper supplements. The safest would be methylcobalamin, adenosylcobalamin & hydroxycobalamin, the first 2 of which are already in the bio-active form. It seems wise to ingest a sublingual version of one of those 3, in case there are any intestinal absorption issues. Can nutritionfacts verify this?

    • Cyanocobalamin is the best source for nearly everyone. It may not be wise to rely on the others since there are less data on appropriate dosing.

  • “Those are some hard-core vegans” :D

  • Ronald Chavin

    The human brain continues to shrink as it gets older. Vegans tend to have the fastest rates of brain shrinkage because they tend to be deficient in vitamin B12. Even people who eat plenty of meat every day have moderately fast rates of brain shrinkage, although not nearly as fast as vegans. People who swallow 1,000 mcg of vitamin B12 daily from pills have the slowest rates of brain shrinkage:
    CONCLUSION: Even people who eat lots of meat every day should swallow 1,000 mcg of vitamin B12 daily from pills. At present, there is no evidence that swallowing more than 1,000 mcg of vitamin B12 daily will slow the rate of brain shrinkage any better than swallowing exactly 1,000 mcg of vitamin B12 daily, which is a very safe dosage.

  • Gabriel

    I’ve seen the paper of Sheila Callender used in the reference and it does not say that vegetarians where feeding on their stool..

    • Toxins

      I could not find the full text of th article referenced, but the study referencing it does say this “In one of the less appetizing but more brilliant experiments in the field of vitamin b12 metabolism in the 50’s, Sheila Callender (7) in England delineated that human colon bacteria makes large amounts of vitamin B-12. Although the bacterial vitamin B-12 is not absorbed through the colon, it is active for humans. Callendar studied vegan volunteers who had B-12 deficiency disease characterized by classes megaloblastic anemia. She collected 24-h stools, made water extracts of them, and fed the extracts to the patients, thereby curing their vitamin B-12 deficiency.”

  • finkler

    Hi there, in you video you are speaking about getting 47micrograms a day of B12 through eggs, yet, the recommended minimum intake is about 3 micrograms, and an optimal intake would be around 5-15 micrograms.

    Then you speak about the cholesterol of eggs, but you deny the same argument you make for B12 to the cholesterol, namely that the absorbtion rate of the egg’s cholesterol’s very low, at the very least, highly individual.

    • Toxins

      Please continue watching the b12 series, Dr. Greger explains all of the b12 issues throughout them. Also, I know of no evidence showing that we do not absorb the cholesterol in eggs. Can you share some evidence?

  • Julot Julott

    Do we know why absorption of B12 from eggs is very bad compared to others animal products?

  • Hammer

    This is the height of the health living – to start eating one’s own excrement!

  • 7in1

    Would it go down to a place of absorption if hanging up side down making enema at the same time?

  • Sorry, but what do you think about yeast estract? This is false? I tell people that use it as a source of b12, i`m wrong? Thanks!

  • Jane

    What are your thoughts on B12 shots?

  • Y.A

    If B12 is in the animals guts why are they known to be in the muscle too?

    • dogulas

      Because animals eat dirty food with poop on it. The B12 is in the poop and the dirt. They absorb it and it gets into them. Just like if you ate the flesh of a human, there would be B12 in their muscles, which they absorbed from whatever source they got it from (fortified breakfast cereals, flesh of other animals, supplements, whatever).

  • SJL

    Dr. Greger – Many thanks for your website and all the effort behind it. It is truly appreciated. I have three young children (ages 6, 4 and 2) and have moved my family to a primarily plant based diet over the last two years. While I fully believe it is a superior diet to the traditional American diet, I am often concerned my children (and husband and I) may be missing critical vitamins and/or nutrients. I only recently learned of your website and have been pouring through information. Does your current position on B12 align with the posts I’ve found from 2-4 years ago? In short, I believe your recommendation is to supplement with B12 or eat B12 fortified cereals, etc.

    I have no medical, nutrition or dietary related background nor formal training in the area and merely utilize the internet for information, which can be incredibly contradictory. My primary goal is to ensure I am providing my family the optimal diet for optimal health. After reading a few of the B12 posts, I’m terrified I may be doing my family harm by currently not supplementing.

    Thanks in advance for your reply.

  • Dear Mister Greger, I’m really concerned about my health. Despite I use your daily dozen my health is not what I expected. I think I have a vitamin B12 resorption problem and now I try to take it sublingual. But, I saw i n a other video of you that artificial vitamins, like vitamin c, help nothing. (compared to the vitamin c in a apple for example). So the issue that toiling me is, is any vitamin B12 what is not from a bacteria, helpful for me?
    What kind of difference consist between artificial vitamin c and artificial vitamin B 12?

  • monakerbili

    Michael Greger M.D. I’d like your thoughts regarding the following issues, especially the first one:

    – B12 supplementation would play a role in advanced cancer development(1)(2)
    – B12 would be involved in acne(3)

    Also, you said that B12 is produced in our colon, that this form of B12 is assimilable by our organism but can not be because it’s in our colon. How is that possible there would be this bacteria only in our colon and not in our stomach or our small(?) intestine which would make it assimilable by our body.

    [1]: “Elevated Serum Vitamin B12 Levels Associated With CRP as a Predictive Factor of Mortality in Palliative”
    [2]:;2-Q/abstract “Serum vitamin B12 and transcobalamin abnormalities in patients with cancer”
    [3]: “Vitamin B12 modulates the transcriptome of the skin microbiota in acne pathogenesis”

  • I live on the Olympic Penn. Of Washington, my home has a deep well of great water. Do you think I get enough B12 from well water? thanx for the help

  • Macat

    Hello Doctor Greger, I know you recommend vegetarians/vegans to take some B12 supplements. I’m wondering what you think about the studies which showed an increased cancer risks linked to taking B12 supplements. Do you still think it’s better to take supplements than being B12 insufficient? Thanks!

  • CreativeRawJedi

    “There is a better way” to get B12 from a whole food plant source – Jackfruit seeds!
    “According to Purdue University, the fresh seeds are considered to be a high starch, low calcium and iron food but a good source of both vitamin B1 and vitamin B12.”
    Please investigate and let us know – Jackfruit itself is fast becoming a popular western culture vegan meat substitute. I developed many recipes and from boiled delicious jackfruit seeds which taste like sweet chestnuts and mix them into salads or make a hummus with it. Its quite popular in India where jackfruits come from. I don’t have B12 deficiency as far as I know being vegan for 19 years, eating jackfruit seeds for 5. Never had B12 supplements. Love to hear from any experts out there, including Dr. Greger

  • Fainie

    *New question:
    According to recent studies, too much B12 causes acne. Having experienced the deficiency and supplementing with various B12, I’ve found it to be true. Never had a spot in my life until now, I can’t help but wonder. Is there a connection?
    The B12 in question here is the Cyanocobalamin VITAMIN B12 (cobalamin, C63H88N14O14P)Cyanocobalamin ~ Alias: Cyano-5,6-dimethylbenzimidazole-cobalamin ; Vitamin B12 Product name: Vitamin B12 feed cyanocobalamin.
    Methylcobalamin is my preferred B12.

  • Alan

    Dear Dr Greger and staff, and anyone else qualified to comment. What do you think of this study? Is there anything here that would cause you to think we could get sufficient B12 direct from the wholefood source? Thank you, Alan

  • vanrein

    Given that we make B12 but can’t use it ourselves, I have been wondering how meat and milk can contain B12. I suspected the cow’s different digestion system to be the cause. And indeed, if I read correctly, ruminants seem to produce B12 in the rumen and subsequently digest it as we do when consuming B12 with food or supplements.

    • vanrein

      I found that rumen physiology gives a few hints — a kneeding process, free of oxygen, with acidity kept sufficiently low with bicarbonate. And Cobalt occurs more in green leafies than in anything else. Sounds like something we could mimic in a fermentation process hosting B12 producing bacteria… spinach beer, anyone? :-D

  • Kate

    I am wondering if it makes a difference to take vitamin B12 without food. It says on the label to take it with a meal. Does it make a difference? Thank you.

  • mark

    would it not be acceptable to have small amounts of lean beef for B12, as long as we are mostly plant based diet? is the harm mostly in the excessive meat eating.

  • Elina Sxoinaraki

    What about children? My daughter is 2,5 years old. Is it safe to take a supplement of B12? Please share with me a text which verifies your aspect (for typical reasons). Thank you in advance! :)

  • I read on an internet forum somewhere that the sublingual methylcobalamin variety of B12 should not be taken by people who have mercury fillings in their mouth. Is this true?

  • Jason Martin

    Are sublingual methylcobalamin supplements safe to use for people with mercury fillings?

  • Susan K. Snow

    I’ve been “seasoning” my veggies with a yeast product high in the B-vitamins. It’s the only one that keeps me from falling asleep after a meal. Monsanto has genetically engineered most yeasts on which cobalamin is grown, from what I’ve read. At any rate, it does not work for me.

    I tried upping the amount of B-12 in a natural and once organic source of B12, but was told by the staff of another online physician that there was also phosphorous in the mix and that I should not increase the phosphorous. Why? If it is natural and organically grown, what’s the harm. Also, which other source would you –anyone recommend?