Which type of vitamin B12 is best–cyanocobalamin, methylcobalamin, or hydroxycobalamin?

I have followed you for years and purchase your tapes. Met you in Ann Arbor at the food co- op. Is it true Cyanocobalamin b12 ( which you recommend for us as vegans) turns into cyanide and the best b12 to take is hydroxycobalamin?Per Raymond Francis MIT scientist. That’s what his website shows anyway. His comments were it is man made , not natural, and not well utilized. What is absorbed is turn into cyanide. Could you please clarify, help.

David Tunison / Originally asked on Vegan epidemic


Let me guess: Mr. Francis sells hydroxycobalamin supplements?

It’s like the whole coral calcium scam. Calcium is cheap as chalk–in fact it is chalk! So how are you going to bilk people out of lots of money? You sell some sort of special calcium. Same with B12 supplements.

B12 is so cheap to produce that supplement manufacturers try to come up with all sorts of fancy ways to “add value” to products so they can charge $30 a bottle. Unless you’re a smoker, have kidney failure, or base your diet around cassava root, cyanocobalamin should be fine. That’s what I take!

Image credit: epSos.de / Flickr

  • But, is cyanocobalamin from animal sources? In another video, you mention B12 supplements for ~$2/year, was that a vegan B12 supplement? Methylcobalamin claims to be vegan, are there cheap sources for it? Not asking you to recommend a retailer specifically but I just wanted clarification… Thanks so much for the wonderful source of FACTUAL information! Keep up the great work! :)

    • Toxins

      Here are Dr. Greger’s current b12 recommendations

      Twin lab offers good, cheap sublingual b12 tablets and thats what I use.

      • beccadoggie10

        This is terrific and concise information to have. Thank you!!!

      • Luke Enzo Notarantonio

        Is it OK to take a b12 pill that is swallowed whole?

        • Rami Najjar – NF Moderator

          Dr. Greger recommends b12 “ideally as a chewable, sublingual or liquid supplement” I assume for proper absorption.

          • Luke Enzo Notarantonio

            Ok thank you, I’ll get some.

        • Brux

          The Wikipedia entry for B12 talks about how certain conditions can affect B12 absorption in the body. People have have conditions where their digestive tract cannot absorb B12, but as far as I can tell you can always absorb it through the very small veins and capillaries under your tongue, or for some people an intravenous injection. Swallowing if OK if your body can absorb B12, and some people do not like holding a pill under their tongue for 10 minutes or so.


          • Luke Enzo Notarantonio

            That’s interesting, thank you. I guess I’ll play it safe and get some sublingual b12.

      • stepher

        Is this still current or has it been updated since 2011? Thanks so much. Cheers.

    • beccadoggie10

      Some 40 years ago, I used to consume Kal brand nutritional yeast for vitamin B-12. But, I wasn’t vegan at the time. I consumed it because it helped me quit smoking — cold turkey; I also fed it to my dog when I was making my her pet food. She did better on homemade pet food with nutrients added than I commercial pet food and that was before they were genetically engineering pet foods! The veterinarian, Richard H. Pitcairn recommended Kal brand, which I bought at a local health food store.

      I now take Bluebonnet Earth Sweet Chewable Vitamin B-6, B-12 plus Folic Acid. I was looking for a vitamin B-12 that was 1000 mcg. So many have 5,000 or more, which I did not want. I’ve also read in the Nutrition Almanac that vitamins should not be taken alone because they can deplete other vitamins in the body. And, in addition, one of the physicians who subscribe to this list, suggested this Earth Sweet Chewable Vitamin B12 for me, when I went vegan.

      Thus far, I’ve had no problem and it certainly makes me feel better.

      • visitor2013

        Bricker Labs has a liquid B12 with 1000mcg and it tastes great.

  • Susan

    Does cassava root and derived products such as tapioca offer health benefits?

    • beccadoggie10

      Cassava root is a decent source of vitamin C and manganese. http://tinyurl.com/cxaoycc It is a good source of carbohydrates, but a poor source of protein. A predominantly cassava root diet can cause protein-energy malnutrition. http://en.wikipedia.org/wiki/Cassava
      A lot more information about Cassava root is at: http://tinyurl.com/bqd94au

      • Why did Dr. Greger mention that people with cassava root in their diets might have problems absorbing vitamin B12 from cyanocobalamin supplements?

        • Nalani

          it’s not that they’ll have problems absorbing the B12, its the fact that Cassava root naturally contains cyanide in it which would potentially exacerbate the concerns about cyanocobalamin cyanide problem – the cyanide levels from cyanocobalamin on its own will not be harmful. But in combination with cassava, it could become a problem. Cassava is cooked and processed in a way to remove most of the cyanide and make it suitable for daily consumption, but traces potentially remain and you probably don’t want to chance things. Note that this is only a concern for people whose DAILY STAPLE FOOD is Cassava.

  • I would still like to know, leaving prices aside, which is better: cyanocobalamin or methylcobalamin?

  • Fidel Castrati

    Dr. Greger, you aren’t concerned that people who don’t eat as super-healthy as you might not have the ability to unload the cyanide in cyanocobalamin in order to utilize cobalamin? My concern is that for many, cyanocobalamin is too stable a molecule in which the cyanide is not that easily released. Can you dig up some science on the mechanism by which the body detoxes cyanocobalamin and how involved that process is?

    The video at http://bit.ly/toxic-b12 says that cyanocobalamin can actually LOWER
    true b12 levels. Yes, the guy is selling a drink mix with hydroxycobalamin, but i still sense there is some degree of truth in what he’s saying. That is, for some, and more than you might expect, cyanocobalamin might actually be unsatisfactory of even harmful. After all, it is not the way humans have been getting b12 up until very recently in terms of the overall human timeline.

    • Colin P. Müller

      “Yes, the guy is selling a drink mix with hydroxycobalamin”

      That’s really all that needs to be said. I don’t listen to anybody who spouts unproven theories about vitamins, especially if they’re trying to push their lame product on me.

    • Nate Morey

      There is no evidence suggesting it lowers b12 levels, total scam is my theory. That said the levels of cyanide in this vitamin are so small that as he said, unless your already smoking it would do nothing at all. you would have to eat a smll bottle full to get a single cigarettes worth, and that is not recommended anyways. your body needs an increadibly small amount of b12 size wise, so though it has this toxin it wont effect you.

      • Vegan Minstrel

        Aren’t we all smoking to some extent? That is, there are poisons in our air from car exhaust, etc. I don’t want a known poison attached to my vitamin on top of that. I have a feeling one of Dr. Greger’s future videos will refer to a study showing why the bio-active forms of B12 are better for us than cyanide-B12.

  • Deanna

    Dr Greger. Thank you for all of your info / sharing. Regarding B12 recommendations, you say that the Cyanocobalamin should be fine. I wanted to double to see if you feel this is true for Vegans..because 2 Vegan sources I have communicated with recommend the methylcobalamin form of B12 b/c it is the natural form. Could you please share your thoughts, advice. (Would there be a negative to taking the Methylcobalamin form over the Cyanocobalamin form)? Thankyou!

    • We don’t have as much data (in terms of proper dosing and efficacy) on preventing/reversing B12 deficiency in vegans with any other form that cyanocobalamin. Until there is I’m less comfortable recommending it.

      • Mary

        What about the B12 in coconut milk. One cup = 50% of daily requirement. Other plant based milks also have it. I have asked this question on three different sites and have yet to receive a comment. This seems an easy way to ingest enough B12, unless the body can’t utilize it in this form. Please comment.

        • Thea

          Mary: There is nothing wrong with the B12 in plant based milks. Brenda Davis and and Vesanto Melina are RDs who are well respected and have been featured here on NuritionFacts. In their great reference book, Becoming Vegan, they state: “The B12 present in supplements and fortified foods can be relied on and is well absorbed.” from page 127
          Now having said that, I don’t think I would personally incorporate a lot coconut milk into my daily diet. Coconut is especially high in saturated fat compared to other plants. So, you are better off on a daily basis with say almond milk if you can eat almonds or any of the other types. That’s just my 2 cents.
          Does that answer your question?

      • Freddy Wendt

        What are your thoughts regarding this study? http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1296017/

      • Freddy Wendt

        What are your thoughts regarding this study? Freeman AG. Hydroxocobalamin versus cyanocobalamin. J R Soc Med. 1996 Nov;89(11):659.

  • mikeysbro

    I just read this small paragraph on cyanocobalamin and it does not clarify if cyancobalmin is toxic as reported. Furthermore, it is still unclear how the cyanocobalmin found in nutritional yeast is made.

    • sf_jeff

      Cyanocobalamin is made almost exclusively outside the animal and plant kingdoms. I would imagine that the cyanocobalamin made in yeast is actually made by yeast.

      • mikeysbro

        There are many types of b12 though nothing I have read that says that b12 is produced by yeast though red star yeast has added b12 which changes the color to yellow which is my current understanding. In addition, it is unclear where that added b12 is coming from since red star does not reveal the source. Here is an excerpt from wiki ”

        Cyanocobalamin is commercially prepared by bacterial fermentation. Fermentation by a variety of microorganisms yields a mixture of methyl-, hydroxo-, and adenosylcobalamin. These compounds are converted to cyanocobalamin by addition of potassium cyanide in the presence of sodium nitrite and heat. Since a number of species of Propionibacterium produce no exotoxins or endotoxins and have been granted GRAS status (generally regarded as safe) by the Food and Drug Administration of the United States, they are currently the preferred bacterial fermentation organisms for vitamin B12 production.[5]

        Historically, a form of vitamin B12 called hydroxocobalamin is often produced by bacteria, and was then changed to cyanocobalamin in the process of being purified in activated charcoal columns after being separated from the bacterial cultures. This change was not immediately realized when vitamin B12 was first being extracted for characterization. Cyanide is naturally present in activated charcoal, and hydroxocobalamin, which has great affinity for cyanide, picks it up, and is changed to cyanocobalamin. Cyanocobalamin is the form in most pharmaceutical preparations because adding cyanide stabilizes the molecule.[1]”

        Thus cyanocobalamin is a fermented product using propionbacterium ”

        Propionibacterium is a Gram-positive, rod-shaped genus of bacteria named for their unique metabolism: They are able to synthesize propionic acid by using unusual transcarboxylase enzymes.[3] …

        Members of the genus Propionibacterium are widely used in the production of vitamin B12, tetrapyrrole compounds, and propionic acid, as well as in the probiotics and cheese industries.[6]

        France accounts for 80% of world production, and more than 10 tonnes/year of this compound is sold; 55% of sales is destined for animal feed, while the remaining 45% is for human consumption.[6]” wiki

        One could assume that the cyanocobalamin is fermented with the yeast but that is only an assumption.
        The following is a direct quote from Lesaffre the manufacture of red star nutritional yeast

        “What is Nutritional Yeast?

        RED STAR Nutritional Yeast is a primary grown pure culture strain of Saccharomyces cerevisiae. It is a powdered yeast without leavening power, marketed for its protein and vitamin content. This type of yeast is available in both powder and pill form.

        Nutritional Yeast is an excellent source of protein, rich in many of the essential amino acids that complement proteins available from other sources such as corn, wheat, and soy. RED STAR Nutritional Yeast contains an average of 50% protein by weight.

        RED STAR Nutritional Yeast is also a rich source of B-complex vitamins that are important for normal and healthy body functions.

        How nutritional yeast is made

        RED STAR Nutritional Yeast is primary from pure strains of Saccharomyces cerevisiae grown on mixtures of cane and beet molasses. After the fermentation process is completed,”Cream yeast” is heated by means of a heat exchanger and held at pasteurization temperatures for a period long enough to inactivate the yeast. During this holding period, all necessary vitamins are added to meet the requirements of the specific type of nutritional yeast produced.

        The yeast is then drum dried before it is ground and shipped to consumers. The drying process assures that all the cells are inactivated in order for the full nutritional benefits to be available.

        Photo Key:
        A) “Seed yeast” is grown in small flasks
        B) “Seed yeast” is transferred to 1,000 gallon tanks for fermentation (becomes “stock yeast”).
        C) Alcohol from fermentation separated from “stock yeast”
        D) “Stock yeast” moved to refrigerated tanks (“Trade Fermenter”) for fermentation cultivation
        E) Sterilized molasses, air and nutrients are added to “stock yeast”
        F) When yeast is ready to be harvested, fermented yeast liquid is passed through a “Separator” to produce “cream yeast”

        G) “Cream yeast” is heated and pasteurized, ***********necessary vitamins are added*********** stars are my emphasis.

        H) Vitamin-enhanced “cream yeast” is cooled
        I) “Cream yeast” is drum dried
        J) The dried yeast is put through a grinder to produce a fine powder
        K) Nutritional yeast is packaged and ready for shipping

        Visit our Nutritional Yeast site at www lesaffre ”
        Hence my question, where is the cyanocobalimin coming from and is it added or grown on the yeast ? Though no one has been able to answer. I guess I will have to call the company…

        • sf_jeff

          You are right. Red star yeast specifically says “fortified”. Who knew?

          • mikeysbro

            Well I specifically looked it up sometime ago including cyanocobalamin to research nutritional yeast . Which is why I question the safety of using it compared to other types of b12 such as hydroxocobalamin though it seems that very little information exists on the subject of different b12 types.

        • WilliamT

          Dr Greger, I assume this is true in that B12 cyanocobalamin is NOT made by cyanobacteria but instead by propionbacterium, as mentioned above. I was concerned given the issue of BMAA being produced by cyanobacteria correlating with ALS (volume 23 dvd).

  • EJ

    Methylcobalamin versus Cyanocobalamin http://www.apiindia.org/medicine_update_2013/chap139.pdf

    • Jacob

      That article says to take “Cobalimin” and not Methylcobalamin, but Cobalimin is a general term for all forms of Vitamin B12 according to wikipedia. Is it referring to Hydroxocobalimin?

  • Colin P. Müller

    Nearly every source I’ve seen that says
    methylcobalamin is the best is also trying to sell a product.

    • Adam

      I’ve found it to be better. I’ve felt nothing of of cyanocobalamin, even at high doses taken over a long duration. Methylcobalamin, which is NOT expensive ($4.99 for 60 tabs (2,500 mcg
      dose per capsule over at Swanson) is a much more bio-available choice.

  • tanji

    You said that cyanocobalamin b12 was the best unless you are a smoker……..if someone is a smoker, should they not take it?

    • myke

      really. for such a broad population you might figure to tell why smoker’s are advised against it…

  • Adam

    I can’t even believe this is up for debate. Most physicians will tell you that B-12 is poorly absorbed because it’s destroyed by gastric juices. I’ve known several physicians who recommend B-12 injections as the most effective way to make use of B-12. In most cases, I’ve found them to be right. I was sluggish and tired, and my intake of cyanobobalamin was more than the average bear. I felt nothing. About two weeks into a methylcobalamin-containing supplement, I noticed a huge difference that has been sustained. Dr. Greger’s dismissive nature on this matter puts me off.

    • Once you understand the biochemistry involved avoiding Vitamin B12 deficiency and treating Pernicious Anemia(PA) via the oral route becomes straightforward. In my clinical experience I have never had to resort to injections if you use high dose oral medications in the case of PA an autoimmune disorder where the body stops producing intrinsic factor which helps is necessary for the active phase of B12 absorption. See Dr. Greger’s 5 video’s on B12 beginning on February 3 2012. Using injections can be useful in the initial treatment of B12 deficiency. It is important to work with your physicians but there is ample literature to support oral therapy. In addition to PA there are certain inborn errors of metabolism that would require injection. Methylcobalamin may offer a theoretical advantage over cyanocobalamin but it is more expensive… if you go to the website referenced by Toxins it is 14 times more expensive. Cyanide is present in foods so our bodies are equipped to eliminate it. The total amount consumed is important. I am not a physician who believes that “Vit B12” is destroyed by gastric acid. As a clinical matter the use of acid blocking agents and antacids can contribute to Vitamin B12 deficiency. All this said there are individual differences and if methylcobalamin works better for you then cyanocobolamin I would certainly go that route. You need to work with your physician(s) to work out what works for you.

      • Adam

        I hold the personal believe that cyanocobalamin is cheap for a reason. It’s synthetic garbage. Even you conceded that its bioavailability can be trivial. Who cares about cost when it’s your health and well-being on the line? It’s like all the people who gripe about the cost of eating healthy. It’s still cheaper than chemotherapy.

        Right now I’m paying $15.99 to have 60 days worth of a B complex that contains methylcobalamin and also contains medium-chain triglycerides. I can’t imagine that $8 a month is beyond the reach of most health conscious people

      • Adam

        And I just checked Swanson Vitamins and found you can by their brand of methylcobalamin for $4.99 for 60 tabs (2,500 mcg
        dose per capsule). You consider that expensive? You consider that TWELVE times more expensive than the cheap and inferior cyanocobalamin?

      • Veganrunner

        Hi Dr. don,

        Something that hasn’t been mentioned is what is in the supplements. I had a hard time finding a B12 that didn’t have sorbitol. I went through a bout of IBS with stomach cramps and diarrhea. Once I eliminated the sorbitol it cleared up. The B12 I finally found was methylcobalamin drops. (thank you Brian) Have you found patients with this issue with the sorbitol?

        • Concerned Citizen

          I am personally appalled with the amount of products that now contain sorbitol. It is almost deadly for me, and extremely painful for one of my children who suffered from IBS all his life. It is REALLY INSIDIOUS that it is allowed in INFANT AND CHILDREN products from toothpaste to medicines, not to mention many, many foods. Whoever within the FDA has allowed this is truly wretchedly evil; the only other excuse would be complete ignorance, and I daresay that is a possibility, but would bet MONEY on the fact that it is totally a “money-oriented” decision on the part of those who have promoted this BAD DECISION!! When I think of the many infants and children that must be suffering the pains of sorbitol sensitivity, it makes me sick. Having given birth, naturally, to 5 children, I KNOW pain, and sorbitol sensitivity can be equally painful!!

          • nicolaxoxo

            similar to the use of carrageenan in many products. It is a KNOWN inflammatory agent and has been banned for children’s formulas in Europe. But it is a cheap thickening agent so it is in many things like ice creams and yogurts. Even in toothpastes and cosmetics! I learned about it’s harmful nature when reading about the ills of commercial pet food. At the time it was a common ingredient added to thicken canned pet food. Thankfully it is finally becoming less used, thanks to MANY consumer complaints. My allergist warned me to avoid it completely, but many medical professionals don’t even know what it is. Researchers often use carrageenan to purposely induce inflammatory for studies. That shows you how powerful it’s bad effects can be.

    • Jonny

      I have found the same with myself, suffering from a long term fatigue (that is probably a very different ailment than just B12 deficiency). Methylcobalamin from ProHealth is my favorite, at 5mg dose. It has a little sorbitol. I just switched to another brand and it has too much Manitol and dissolves too quickly and cost just as much. The ProHealth one is fabulous.

    • Dani

      I can add that I was taking cyanocobalamin and felt nothing, but switched to methyl and within two days noticed I no longer felt depressed (which has been a chronic condition). So I am inclined to believe that the methyl form works better. But I wish there was some scientific investigation done that Dr. Greger could report on because I’ve read that you need a higher dose of methyl over cyano and I would like to know that I’m taking the correct dosage.

      • Freddy Wendt

        When you say methyl, do you mean hydroxo or just methyl because I was reading that methyl alone isn’t sufficient in preventing B12 deficiency according to this study: Thakkar, K.; Billa, G. (2015-01-01). “Treatment of vitamin B12 deficiency-methylcobalamine? Cyancobalamine? Hydroxocobalamin?-clearing the confusion”. European Journal of Clinical Nutrition 69 (1): 1–2. doi:10.1038/ejcn.2014.165. ISSN 1476-5640. PMID 25117994.

  • Optimus

    I think the point for not just vegans but for anyone who is health conscious is to choose healthier foods and to remove as many synthetic products from your body as possible. It maybe fine for others to take in Cyanide if they choose, more power to them… but lets not take away all our healthy choices simply because its cheaper…Has everyone gone mad with the money bug….If its not naturally found in my body why put it in there?……
    Cyanocobalamin when digested becomes methylcobalamin then leaves the cyanide behind.. although at none toxic levels, but can bioaccumulate….
    Methylcobalamin is a very good and benificial source of B-12 although a bit more expensive..but it can be synthisized by chemically processing Cyanocobalamin..
    they just mimic human digestion..this way you can get B-12.. still get a good price and not get the cyanide…
    Hydroxocobalamin is natural.. and is the very best form of b-12 and very expensive… not only do you get the neurological benefits.. there are molecules in it that bond with cyanide in the body and allows it to be removed through urination..so just like all natural products it detoxifies..and does not toxify the body

    • myke

      where are your sources?

    • Alex

      Cyanide is also a natural product. Does it detoxify?

  • With this in mind, we can check out the various nature made vitamins that could possibly give us the exact vitamins that we may be lacking in. These natural vitamins can boost our immune systems, give us our Daily IU of Vitamins A, C, D plus B complex and other vitamins that we could need.

  • Jason Smart

    If you have MTHFR which up to 80% of the United States has, you have to take the co-enymated (enzyme activated) methylcobalamin

    • Holly

      could you please post a reference?

  • Lauren Vita

    If you have the genetic mutation mthfr, any b12 other than methylated turn into cyanide. My son has this ans we give him methylated b shots.

  • superape

    My mom’s only got one kidney left that only works for 30% but I got her into taking this form of B12. Should she stop taking it and start using another one?

  • superape

    Can someone please answer my question? I´m a bit worried now and I really don’t know who else I can ask this. Thank you :)

    • JacquieRN

      Hi superape. Since kidney disease can result from several causes, the type and amount of B12 should be closely monitored by her MD. I say that not to dodge your question but since people with kidney disease have limited kidney function, taking high doses might allow unhealthy levels of the vitamins to remain in the blood.

      • superape

        Thank you very much for answering my question Jacquie! I told her that maybe she needs to take another type of B12 and she´s going to ask her nephrologist. I will also tell her to ask him about the right amount ’cause I told her to take 1000 mcg a day as she is 66 years of age. Really thought I was doing the right thing for her… Thanks again! It’s much appreciated :)

        • JacquieRN

          My pleasure!

  • edvilla24

    Thank you Dr. Greger ..muah!

  • ioana

    Hi Dr. Greger,

    I have been vegan for the last 2,5 years. Two month ago I decided to take a daily dose of B12 (methylcobalamina spray) to supplement my nutrient intake.

    I noticed that my lips have become chapped and dry and for the last 3 weeks an acne like rash is bothering me.

    Do you think these could be the result of overdosing with B12? Or that I show an intolerance to the product?

    Wikipedia says B12 overdose could lead to acne-like rushes:



    • Paul’s Stuff

      Hi Ioana,

      I don’t know how much B-12 you are taking but the body only requires 5 micrograms a day. That’s right micrograms not milligrams. Nobody makes dosages that small. So if you just take one pill a month of any brand you are getting all you need. And that assumes you are a strict vegan and have been for at least three years. If you are eating any meat at all you probably don’t need to supplement your B-12. My source on this is Dr McDougall.

  • Kristine

    What if you are a smoker? Which is best to take then? And does it help?

  • Mari

    Hola Dr. Greger. I would like to know your thoughts about B12-cyanocobalamin injections (1000mcg). Is it true that it is a better way to make sure you are absorbing the vitamin?

    I already started taking it. One inyection a day per one week, one a week during one month and one per month to mantein the levels.

    I didnt find anything about inyections in your videos or webside and really would like to know what you think about it. Thank you for everything. Greetings from Spain!

  • April Egan

    Our unless you strive for an actual healthy lifestyle! Cyancobalamin being the most widely used form dies not make it the safest form. I seek nothing. I am a SAHM mother of two that actually researches what I put in my body and in that of my family. There is plenty of information from various sources, including the encyclopedia, concerning cyancobalamin. It does not occur in nature, and for me that’s the biggest red flag there is. The fact that a medical professional would actually recommend cyancobalamin over other safer, more natural forms disturbs me greatly. Do your research- there’s a reason why ‘side effects’ are listed for cyancobalamin and not for other forms.

    • healthy Doc

      methyl cobalamin is ‘ready-to-eat’ by the body. Other forms need to be first transported to the liver to have the CH-4 (methyl group) added, then released so it is ‘bio-available’.

      • bub

        Actually Hydroxycobalamin is the most bio-available form, as Methylcobalamin gets converted to Hydroxycobalamin in the body, though the Methyl component is needed for multiple reactions within the body anyway (ie: it is good, not a waste product). Also, for those with too much cyanide in the body, Hydroxycobalamin will combine with cyanide molecules, and allow it to be excreted via the kidneys. Thus, it is used in cyanide poisoning cases.

        Many people with heavy metals in their bodies, and other toxins that over tax the liver, cannot easily convert Cyanocobalamin to Methycobalamin, so the Methyl version is preferred. It is also preferred over Cyanocobalamin if you are wishing to follow studies showing that doses of 10000mcg are required to get the higher energy results desired, as well as for those with low B12.
        At higher doses, Cyano version would give you significant levels of Cyanide which would further tax your liver, and is poison, period.

        Hydroxycobalamin is best intravenously (in terms of bio-availability), but needs an anesthetic administered with it, as it “burns.”

        Overall, from a cost and health perspective, orally, methylcobalamin is probably the ticket, and if sublingual, has been shown in studies to be just as effective as shots of B12. It can be bought at most Sams and Costco’s at the most affordable prices I could find readily available anywhere for high-dose Methylcobalamin.
        I can also state that it has proven nearly miraculous results for me with seasonal allergy relief. Check out B-12 and how it naturally suppresses immuno-over-response, if you have bad upper-respiratory allergies…not a permanent “cure,” but lowered my spring allergic reactions to nearly nada.

  • disqus_3BrONUAJno

    I assume you also take the potentially poisonous folic acid instead of a more bioavailable form of folate that won’t potentially build up in your bloodstream like homocysteine, causing the same problems? Cyanocobalamin is about as bioavailable as the iron in nails, since your body has to strip the cyano-complex off and add the methyl to use it.
    Do us all a favor and chew on some nails…

  • Joel Santos

    Hi Dr greger, the cheapest b12 supplement I could find already has b1, b2, b3, b6, c and calcium pantothenate in it. Is that okay? It costs around 2 cents per tablet

    • Vee

      Just wondering where you found them for that price. Very interested….and are they working for you?

  • Michael

    I think everyone should read the following website that compares the three types of B12 in a succinct, but very informative fashion. My conclusion has been that methylcobalamin is the best choice for many reasons, including that it is a methylating agent, decreases homocysteine, and does not deplete glutathione as both other forms can. But toxicity is also a major concern. Cyanocobalimin is inferior when it comes to absorption, toxicity, GSH depletion, dependence on intrinsic factor, and more. This article is very well referenced.

    • bltw

      So what’s the website

    • MyaSavage

      That’s frustrating.

  • MTHFR Kiki

    If you get your genome mapped by 23andme and run it through knowyourgenetics.com engine, the proper form of B12 specifically designed for your genetics will be shown on page 16 of the resultant MPA report. So while I was supplementing with MTHF folate for my MTHFR defects and some types of B12 (I think I found a supplement containing all types of B12), once I changed to the two forms recommended for me by that table that takes into consideration your heterozygous and or homozygous mutations of COMT V158M and VDR Taq, my recommended types were hydroxy and adenosyn, and I tell you it made a WORLD of difference to me. Same with husband who had cognitive difficulties (misdiagnosed with Alz, but probably was simply a B12 deficiency). Once I got him on the right types which was basically all types plus more Methyl, it made a WORLD of difference for him.

  • Dietician in training

    Hi Dr. Greger,

    What about people who have the MTHFR mutation? Wouldn’t methylcobalamine be the best option? I am just curious because I recently found out that I am heterozygous for one of the MTHFR mutations (SNP). On that subject, I would really enjoy a blog post or video about this mutation because it does have far reaching implications in nutrition, and there are quite a few people that have these SNP in the MTHFR gene and sadly most of our doctors don’t really know what to recommend as far as proper detoxing, supplementation, etc. Just thought it would be an interesting read or watch coming from you!

    • dogulas

      That’s interesting. My wife and I take the same B12 supplement, but my serum levels are much higher than hers. I wondered if it could have been genetic (or if the test was just badly done). Have you had your B12 tested?

    • Lisa

      My husband has this mutation too. The Hematologist & Neurologist have him taking Rx Cerefolin NAC 1x/day (Folic Acid 5635mg, B12 1mg, B6 50mg, B2 5mg) and 1 injection monthly (the first few years was weekly) of 1000 mcg/ml Cyanocobalamin. What they explained to us was that mutation does not allow the body to convert food (vit B’s) to a form he can utilize. Hence his off the chart Homocysteine levels, heart disease and seizure disorder….now all under control.

  • MTHFR Kiki

    The different forms of B12 are not alike. Cyancoblamain converts to hydroxyl which converts to methyl and adenosylcobalamin. Adenosyl is the only form stored by the liver. Hydroxy has a longer half life than the other forms. BUT, even more important is there is a combination of B12 that is right for you based on your genes. If you run your 23andme.com genetic results through the engine at knowyourgenetics.com, you will receive a Methylation Pathway Analysis, and in the middle of that (page 16 or so) is a table that
    recommends the different forms of B12 for you depending on primarily two genetic mutations COMT and VDR Taq. I am a no methyl person, and I could really tell the difference when I started supplementing with just hydroxy and Adenosyl B12 forms. My husband is a methyl person and does better with primarily with half Methylcobalamin and half all the other kinds. Helped him with cognitive problems, memory, energy and me with depression, energy, outlook. So Dr. Gregor’s analogy to the coral calcium scheme is simply dated. Nutrigentics is a new field and any doctor that isn’t getting on board is not your best bet. Encourage your doctor. Info on how to use the 23andme data to generate useful reports to aid your health can be found on the Armchair Genetics blog on mthfrliving.com. Good health and God Bless!

    • hopesteph

      Do you or your husband mix the different forms to together/take together in one ingestion? Or does methyl need to be taken on one day, other B12 forms on other days? Thanks.

  • hwf

    Dr Greger recommends cyanocoblamin B12 supplements “unless you’re a smoker, have kidney failure…etc” I have been a vegan for just under a year and I have mild stage 2 kidney disease. Therefore, should I avoid cyanocoblamin and invest in the methylcobalamin or another form of B12?

  • Ernest

    This is the information I have regarding B12.

    Deficiency can be serious, so its convenient to take a pill.

    Absorption rates go down on megadoses (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2532799/table/T1/#TF1-4

    so, you have to do the math.
    Cyanocobalamin is a lot more studied than the others (and proven efective). It’s also very stable. It has a little cyanide, but that is no problem for the body unless you have serious disease.
    Methylcobalamin is theoretically better once in the bloodstream, but is very unstable. There are some studies that prove some benefits (as a methyl donor) unrelated to B12 deficiency. As it is very unstable, doses need to be higher.
    So, cyano is a safe bet. Methyl seems better but it is unstable (not so reliable) and not so well studied (there are some).
    What do I do?, I take 500mcg (micrograms) cyano and 1000mcg methyl alternating every two days.
    If I had any deficiency, I would take cyano.
    Nowadays, they are both pretty cheap…..

  • bobc514

    Why is the daily recommended amount of B12 250mcg if that is 4,000% of the RDV?

    • Alex

      Because you can absorb less than of 5 mcg via intrinsic factor, then rest is very poorly absorbed (<1%) by brute force.

  • Wade Patton

    What’s the “smoker” and cyanocobalamin problem? Does the smoker need more or less or a different form? I am not a smoker of tobacco but they have asked for clarification below.

  • Wade Patton

    Hey what’s this thing about cassava? I just had cassava root based lunch.

  • Brux

    So, there is nothing wrong with Methylcobalamin as a source of B12?

  • MaryAnn Egan

    Can you tell us where Dr. Gregor gets his B12 for $2-3/year?

  • danieltb

    If this is true (and there is no difference between the cobalamins), why are other seemingly sincere (not greed-driven) people furnishing arguments for the superiority of methylcobalamin (e.g., i. Mike Adams http://www.naturalnews.com/032766_cyanocobalamin_vitamin_B-12.html; ii. ) – and how would Dr. Greger respond? I read that Japan only used methylcobalamin and that methylcobalamin does fantastically at ameliorating B12-deficiency-based brain issues where the others either underperform or do not perform at all.

    I think it would be really helpful if Dr. Greger made a video clarifying this issue.

  • Love2Learn

    IF the RDA of B-12 is 2.6 mcg/day, WHY are over-the-counter supplements sold in sublingual tablets of 1,000 mcg?
    (The bottle I bought has B-12 as cyanocobalamin.) How often should one tablet be taken?

    ALSO: After reading ALL of these comments here from over the last 3 years, is there a definitive answer to the question:
    WHAT TYPE of B-12 supplement is most effective/safest/BEST?

    Thank you

  • danieltb

    I started getting acne after starting on the cheap B12 supplement you recommended (from Nutra Bulk). I looked around and learned that this is a common complaint of people supplementing B12; but the people from Global Healing Center said they have not received *one* such report that their B12 (specifically methylcobalamin) has caused anyone acne.

    What’s in my B12 (not methylcobalamin) that is causing me to break out that isn’t in the B12 from GHC (Dr. Group’s Global Healing Center)? This acne can’t be a good sign.

  • Pookey Zi

    Dr. Greger, what would you suggest for me, a woman who wants to follow a plant-based diet (currently vegetarian), but has a cobalt allergy which prevents me from taking B-12?
    I’m hoping to get a second opinion about the cobalt allergy in the near future.

    • Alex

      I’m not a doctor, but as far as I know, you require cobalamin.

  • bgrogan

    If I take more B-12 a day a 3 a day 250 mig is that ok or can you take too much ? Also I am taking a 500 mg gel cap of omega 3 a day . I couldn’t find a 2500mig tab for once a week. how much is too much ???

  • Dani

    This website (see link) says the methyl form of B12 is better than cyano because you don’t have to convert it. What do you think? I read this elsewhere as well. http://www.health101.org/art_methylcobalamin.htm

  • Louanne

    Methylcobalamin is superior B12. Plant foods are Methyl foods thus Methyl version is best! (study of cancer in twins (sharing same DNA) but one had cancer and the other no cancer showed it was due to eating a lot more Methyl (plant) foods!!!)

  • Menace

    I think most of you are worrying yourself about things that are really not fully understood yet. The best forms of B12 is what wworks for you. Listen to your body and get your bloods checked occasionally. Personally, I’m mainly plant based but I make a point of eating 2 or 3 portions of steamed clams a week. That is my source vitamin b12 ande I’m in good shape.

  • On some internet forums, someone claimed that the sublingual variety of methylcobalamin vitamin b12 could cause problems for people who take it if the consumer happens to have mercury fillings in their mouth.

    Does anyone know if that’s true??

  • Jason Martin

    Is there a hazard associated with taking sublingual methylcobalamin B12 if you have mercury fillings? I think I heard somewhere on the internet that this was not safe, but I wanted to check.

  • John Noble

    Hi! love the book, the vids, the blogs and the attitude!!!

    I consider myself informed enough to have made the switch to a plant based, whole food eating regime and feel great for it…

    I’m concerned about vitamin b12 and as such have been looking at supplements. i understand Cyanocobalamin is preferred due to the fact that more studies have been carried out on it, however the supps i have found contain magnesium stearate. i am lead to believe that magnesium stearate is not safe however i cannot find any particular studies or info on this. can anyone point me in the direction of some convincing information from a credible source to help make a sensible decision?
    Really appreciate the service!!!

  • Carol Sikora

    Hi Dr. Michael, I have a question regarding age spots (sun spots). I have looked at all your info on skin videos,but is there something I can topically do? I am a organic farmer,WAS a sun worshiper in my earlier years, but now use hats, natural sunscreen, Iam vegan and eat broccoli,collards kale,beets on a regular basis besides our own fruit,nectarines,peaches,cherries,blk berries,rasberrries fresh from the vine.And many more foods i grow. Is there any herb, lemon I can do?