Can a very high B12 blood test result also mean you are deficient somehow?

It does sound contradictory I know. But my husband has so many symptoms that indicate he's B12 deficient - peripheral neuropathy, orthostatic tremor, wide based gait and imbalance, IBS, tinnitus - also quite withdrawn and depressed. But his blood tests results were about 2000! Surely this indicates some sort of issue with B12. He doesn't have anything wrong with his liver either.

Doc is naturally not taking it very seriously as the levels aren't low.

Can anyone advise?


58 Replies

  • It could be a B12 deficiency, due to different reasons. But, your decription of his symptoms made me think of fibromyalgia, link for which I attach below. Those with fibronmyalgia have IBS, depression or/anxiety, and limp movement, even while asleep. I suspect I suffer from it for over thirty years, Like your husband, I have high B12 in the blood pool, but not active B12.

    I supplement with 5,000 mcgs of sublingual.

    Other members provided in other answers the link to contact to have the appropriate active B12 test done.

    Good luck to the two of you.

  • I wasn't under the impression that fibromyalgia has remarkable neurological symptoms?

  • Thanks so much for your reply.

    I don't think he has fibromyalgia but he does have ankylosing spondylitis! It is a separate issue I think but I need to ask a specialist about that.

    Can you explain what you mean by high B12 in the blood pool but not active B12?

    We are new to this.

  • I had asked this question about the Active B12 before but could not locate mine and the answers I received, but instead found this reply from member Marre from August 2012 to another member:

    Hi Irene,

    My Daughter had the Active B12 test because she was taken off B12 jabs, as her levels were "normal" (serum B12 300), and she hates them. After 7 months of no B12 treatment (having been on B12 jabs for 3 years) she agreed to have the Active B12 test done (for me), the result suggests she was B12 def again, After 7 months her serum B12 had sunk to 230.. She got one cold after the other, infections etc, was became iron def again etc.

    Her results re: Active B12test, was 28 pmol/L (lab range 35 - 141), Active B12 concentrations under 25 pmol/L suggests B12 def, vitamin B12 can not be excluded if Active B12 (holo TC) concentration is inbetween 25-35pmol/L, because of her result her blood sample was referred for mathylmalonic acid (MMA) analysis, her MMA was 433 nmol/L (ref range 73 - 271), MMA is above the upperlimit this result suggests functional vitamin B12 def at tissue level.

    So she is back on B12 jabs for life now. Not that she is good about getting them on time..

    So some are fighting to get more frequent B12, whilst others are fighting to get off them..

    I hope this helps,

    Kind regards,


    And, Queenie you should try: for more information.

  • Thank you so much for all that info. I am pursuing the new Active B12 test.

  • I think B12 cannot work properly in the presence of Folate deficiency because I had some B12 but my folate was in my boots and I am sure I read that somewhere when I found that out. I still take B12 as it was low in range when I try to replace some folate.

    I know you can't take folate with low B12 in case of the folate trap, you might want to check out his levels of folate?

  • That is incorrect. If your B12 is low, you darn well need to be taking folic acid or folate in order for the B12 to work.  It is low B12 that will trap folate but once you treat the low B12, folate becomes untrapped.  B12 needs folate as much as folate needs b12..they are interdependent on each other.

  • Will do, thanks.

  • High serum B12 can be caused by a functional B12 deficiency. In that condition, there is enough B12 in the body, but the cells are not able to use it properly, so they export it back to the blood, and it builds up there, bound to haptocorrin. After about a week, the haptocorrin-bound B12 is imported by the liver and recycled via the bile to the gut. This is the salvage and recycle pathway for B12. The cells of the body in general are not able to use this B12. Only the liver can import it. The other transporter of B12 in the blood is transcobalamin, and this is the one that carries B12 from the gut to the cells in general.

    High serum B12 per se is not harmful, but it indicates that there is an issue with B12 utilization.

  • hi

    I know it's been months since the last posting but I really need your help guys.

    I have a 28 months old baby boy that is slightly delayed and I have been researching and came across the vitamin b12 articles and since he doesn't take any eggs or meat and is allergic to dairy products I asked his pediatrician to check his b12.

    I have suggested the b12 shots to the doctor even before the results because I was so sure of him being deficient. I received a call two days ago the pediatrician telling me to stop the b12 supplements because the results show an elevated b12 in the blood. I tried to explain to him that I wasn't giving him anything but he wouldn't listen. I was shocked by these results , how can a person have an elevated b12 and consume very little foods that are rich in b12 ??

    I came across this answer and I think it is the most logical explanation. please explain more the b12 not being used by the cells I mean the reasons.

    thanks a lot

  • Hi Miaa

    You are quite right, as I have stated below, a person can be B12 Deficient at any Blood Serum level reading. This test is about as much use as a chocolate teapot. The B12 reading which is important, is the Holotranscobalamin level (aka the Active B12). this is acquired via a test called HoloTC level reading. In simple terms, this indicates the amount of B12 that has past into the body at CELL level. If this is found to be low ( also know as being in the GREY area ) then it is necessary to conduct an MMA test to substantiate the true levels and as your child is on a very restricted diet, then also checking VitD and Folates might also be a good idea. Please see my format for B12 testing here below.

    Hope all's well and everything works out ok.

  • Hi B12 Turbo

    Thanks a lot for answering.

    I'm going to discuss that with the pediatrician. By the way his folates levels were also really high. I took him to a hematologist a few weeks ago and he just didn't want to investigate my theory. He said : "we don't know what causes high B12 levels in children. I would suspect a leukemia if he was older"

  • Hi Miaa

    To begin with I think you will find that elevated levels of B12 are understood and you may well find that in simple terms, it may simply be a matter that the B12 is being recycled, but without a fuller picture and a better knowledge I personally would prefer to pass this on to a better brain than my own on the subject. If you wish to contact Denise Oblein at Guy's / St. Thomas's Hospital in London on 0207 188 7188 and E mail her all the details you have, including blood results, copies of which, if you do not have them, should be available from your GP, you have a legal right to this information and should have no problems obtaining it. Then I will also contact Denise and out line your needs. I personally think this should be looked at by Dr. D. Harrington and his team. Dominic is a great and very well informed chap, who as the Director of Medical Research, also has a team of specialists working full time on B12 problems. I will also E mail Dominic directly and request his personal help in this matter if you so wish ??? Please let me know what you intend, prior to contacting Denise, so that I can prepare the ground so to speak.

    I really feel this is the best place to find the answers you seek, answers upon which you can both really and comments upon which your GP can base your child's best future treatments. My wife and I now both well retired and proud Gt. Grandparents, both love children and always hope they go on to do well in life, we therefore sincerely hope you ( with a little help) you can find the answers you need. Good luck B12Tx

  • Hi I know this post is a old one but I'm hoping someone will see my post ? I was receiving B12 injections as suffered from neuropathy and dizziness etc .. The GP stopped them last May 2015 as he said my levels were high and wanted to see if they would decrease without injections ?  I also became hypothyroid :( already have coeliac disease :( 

    My GP did my bloods on the 1st April 16 as I thought I needed a increase in thyroid meds as have bad pains in my arms and weakness :(  My bloods came back and my B12 is still sitting at 2000 and I've not supplemented at all :( all I have taken is B1,B2,B6 as I had private bloods which showed a deficiency and low vitamin E bloods also show high for red blood cell count ,neutrophils, heamocrit and lymphocyte and what with high b12 I'm concerned about PV ?? .. My question is would I still be able to contact Denise at Guys / st Thomas hospital as would like to have a b12 that checks if it is getting in my cells ? Or if there is a problem with absorbtion ? Well must be as my b12 blood is exactly the same as a year ago :(  Hope someone can see my post many thanks in advance Lynn xxxxxx

  • Hi . I am having the exact same problem as Lynn. I have hashimoto/ hypothyroidism. My b12 levels are always above 2000 extremely high. My primary doctor and my endocrinologist cannot explain this. I am not supplementing. My doctor said its in all the food we eat. I am not happy with this explanation.

  • Hi shana112 I too have Hashimoto's I'm seeing GP in the morning as some of my bloods on full blood count are high and worried about polycythemia Vera ??  My liver function was ok as they say that if b12 is high could be a liver problem ? 

    I really hope someone will reply from the original posts ? .. I'm having trouble with my hypothyroidism don't need anything more :(  keep in touch let's hope we can get to the bottom of it ? Take care Lynn xxx

  • See if you can check your genetics for any mutations.  I have mthfr and I can't absorb b vitamins but I have extremely high levels of them I guess because they're not being absorbed properly.  I have to take folate that is already methylated in order to absorb it. 

  • Can I ask which polymorphism? And did you tolerate the methylated vitamins well, and do you have to take high doses?

  • Having a mutation in the MTHFR gene makes no difference to absorption of B vitamins. It is the processing of folate that can be affected. And the most common mutation (heterozygous for the 667C>T mutation) the processing is not affected to any large degree.

  • It is true MTHFR does not directly impact b12 absorption, but folate is a B vitamin.

  • So what? MTHFR does not affect absorption of folate.

  • I also am interested in finding out this question since I have a B-12 level of 2000.. with no supplements. I am 71 years old and have always had a "normal" B12 test until my labs Sept. 28, 2016. Why the change?

  • This really is something that you need to ask your GP. Some of the causes of a high level of B12 without supplementation can be serious.

  • My friend is an alcoholic and her recent b12 measures 2000. Not utilising it I guess. She doesn't supplement or have p a or anything. Her folate was only just in range.

  • I do think there's something to that.

  • Hiya I'm tea total don't even drink wine .. There must be other tests to find out if I'm using it in my body or not ? Getting worried about it as can be a sign of cancer 😥 Waiting for heamotologist to look at my results :( xxxxxx

  • Isn't high b12 in the absence of supplementation potentially a sign of liver problems?

  • Yes it is but liver function came back ok ! So just a bit worried why so high at 2000 with no injections or supplement ?? Xxxxxx

  • I also have high b12 at 3, liver problem blood count red/white normal..have you gotten any answers

  • Hi saramacias7 no not yet 😰 I've got more bloods on the 25th .. My liver function was ok but my white blood cells were above range as was my red cell count and lymphocytes .. I looked back in my diary and I've had injections from 2012 to 2015 and lots of people have said it takes years got the numbers to drop ? Have you been having injections ? Or taking supplements? I haven't for a year so GP is checking for other things ? I thought it was my liver as my palms are always red :(

    My lived function came back ok ., I've stopped all my supplements just taking thyroxine and my propranolol and amitriptlyne ., so have to wait :( yours is higher than mine has your GP said anything ? Will post back on here my next results xxxxxx

  • my hematology/oncology Dr said red/white blood count normal..they can't find answers for high b12 since my liver is fine ...I am you..please keep me posted wishes 😊

  • I know it's a worry ;( we're you taking supplements or injections ? Will keep

    You posted try not to worry fingers crossed its just us ? Xxxxxxx

  • Hi Lynnwin, I have very high b12 of 1777. I am also very worried. Any updates yet?

  • Hi Tashee I'm going for more bloods tomorrow 😢 Still really worried have you taken supplements or injections ? Will update on this thread when I get my results ! Has your GP commentedon your high level ? Xxxx

  • any news on your results? mine was also high, 1660 pg/ml. Liver and blood tests were found ok. waiting for kidney test...

  • Hi Don_Lazaro

    My bloods came down but NOT my B12

    Had private London bio lab blood results and B12 still really high spoke to a guy at bio lab and he said we have lots of people with very high B12 and no explanation for it ? I was also told it takes years for B12 to come down after injections ? I haven't retested again mainly because I feel ok and I'm frightened to test ☹️ .. were you having injections ? .. my liver kidney was ok .. as I did worry as I only have one kidney ☹️


  • hi lynnwin, never had any injections before and it's my first time to find out my high level b12... was your 2000 pmol/L or pg/ml?

  • Hi the NHS Ines were 2000 pg/ml

    And bio lab was

    Active B12 >256 pmol/L

    Bio labs range is


    Try not too worry if your bloods all come back ok then I wouldn't worry .. I have coeliac disease and had some neuropathy so had the injections every 12 weeks but as my post above not took supplements or had injections now for ages '

    I was worried when I found out that it could be a sign of something sinister but thought I'm not going looking for it ! What has your DR said to you ?

  • the doctor seem puzzled and my concern is that he can not explain it... thanks for replying to my message, appreciate it a lot! it's very informative 😀

  • anyhow, what did your doctor tell you?

  • Hi my doctor didn't really do much either other than said re test ..I will try and update on Here in May as that when I will check again as a year would have passed .. Take care update me to please if you get any joy ? Xx

  • i will, for sure. take care and God bless!

  • kidney test came out excellent. went to another doctor (great decision) and was very helpful in explaining. She said that no need to worry about it, it may just take quite some time to flush out B12 in my system. Just need not to take any supplements in any form 😀

    I wish everything goes well with you too!

  • Hi Don and Linwinn- were you both supplementing with those high b12 numbers?

  • hi Lisa, no supplements from my side.

  • hi I used yo live in him I was diagnosed last Oct as pa, suffer all the symptoms, now been told that I am not p.a. and no longer need injections here in Ireland, as my but b12 very high been told my diagnoses wrong! no one can explain the diagnosis? does this mean that I was wrongly diagnosed and never had pa if my b12 very high! ? if so why I was told I had pa in the first time? and why the symptoms? Maybe I am depressed and a hyper chondriac! also is it possible to be cured of pernacious anaemia?

  • Hi Queenie 123

    Regarding your husbands symptoms, many of which appear from what you say, could possibly be attributable to a B12 deficiency, there are procedures which should be followed in order to ascertain his true B12 status. I have outlined a standard set of rules which indicate the best way to go in such cases, they are as follows:-

    Self admin is not a good idea prior to being fully tested. Once you have taken B12, you should then leave a period of at least 3 months without taking any B12 prior to testing, otherwise your results will not provide a true natural body level reading, they will show a medicated reading. SORRY!! but that's the way things are at present.

    If you wish to find out if you are B12 deficient, then there are procedures to follow, if you are wise. First attend your GP and ask him to carry out his standard and almost useless B12 Serum level test, which in any medicated state, is almost certain to be normal in your GP's eye's. Of course he may not be aware, that you can indeed be B12 deficient, with any Serum level reading. This should then be followed by a test for Intrinsic Factor and Parietal cell Antibodies, all of these tests are available free on the NHS. These tests will highlight your ability or inability to absorb B12 via your gut and hence your diet / oral admin route. Whilst on the same visit, you could request your GP's backing, in order to obtain blood samples for HoloTC testing and if needs be, MMA levels. From what you state, your husband could also be Vit D and Folate deficient, these should also be tested fully. you should also in my opinion, consider a test for Homocysteine, which will further indicate both your B12 and Folate status.

    Advice on HoloTC, MMA and Homocysteine testing can be sort from Guy's / St. Thomas's Hospital in London and tests can be completed by post. You could contact Denise O'blein on 0207 188 7188, Denise will outline the procedures for arranging tests by post, you will also be able to E-mail her all your medical questions and she will then run them past the Constants and experts in the field, answering them all by return of E-mail, which you will be able to refer to in the future, perhaps with your GP.

    You also mention imbalance and hearing problems, these could also be a Neuro. problem, for instance the 8th Cranial Nerve affects both hearing and balance and a problem with the Myelin Sheath is possible. May be not, but possible, yes in my opinion. I have no wish to alarm you, but as you mention a gate problem, although my knowledge of this is limited, I understand that variations in gate, CAN POSSIBLY be a sign of the early onset of Parkinson's Disease, so that might be worth a mention to your GP, and a visit to a Consultant in that field.

    IF your husband is found to be B12 deficient and is diagnosed with Neuro. problems, then the latest research is indicating that treatment with Methylcobalamin is far superior to Hydroxocobalamin used in general by GP's. Methylcobalamin has been found to have an ability to repair the Myelin Sheath around nerves.

    Hope all this helps and you soon have the answers you seek.

  • Hi B12 turbo,

    I hope your still active on this site as as this post is 2 years old!.

    I have an unhelpful gastroenterologist and GP and can't figure what's going on with my bloods. And wondered if you could shed some light on them

    For the last few months I have had low red, white, blood clotting, lympthnocytes, neutropenia and high b12 and slightly high folate.

    A month on to my most recent blood test that last showed these results now shows everything gone back to normal apart from my b12 and folate. Also my thyroid has started to go hypo. Recent reading b12 is 1302 (increased by 100 since last month) folate 18.9 and thyroid t4 8.7 t3 and tsh normal.

    I won't go into great detail with my health issues or symptoms as I'm sure I'm being cheeky asking for enough of your time reading this. But if u would like to know, I'm happening with telling you.

    with how my bloods have been before the most recent blood test has worried me as it all fitted in with being bone marrow related. I also am confused how after having repeated problems with my bloods how a lot of them change to being normal all of a sudden...

    I know theirs more to my b12 and folate and sure I'm deficient as I was in starvation mode for many months due to my GI problems and my b12 where still raised then.

    I've just started supplementing gluthathione and if I where to get certain tests done that u have suggested above, would this supplement interefe and mask the real/true reading/result?

    Any help or advice would be much appreciated


  • Hi Loretta have you now got things sorted with your b12 .? I'm having similar problems as my b12 is over 2000 ..I did have injections a year ago as I have a neuropathy and they helped but my GP stopped them and now a year on with no injections and no supplements I'm still the same :( ..I have coeliac disease and hypothyroid :( I am worried about the high b12 and had some problems with my full blood count :( 

    Just wondered if you have sorted it now ? Take care Lynn xxxx

  • Hi Queenie123 Apart from a very high B12 assay, there is a lot of other information that your medical adviser's should be requiring. However purely regarding B12, there is research which indicates that where MMA and Homocysteine are raised, then one may consider a possible deficiency, irrespective of the B12 level. However a very high B12 assay can also be an indicator of other problems. Might I respectfully suggest that you seek expert advice from perhaps Guy's / St. Thomas's Hospital. You could try ringing Denise O'blein on 0207-188-7188, Denise is the P.A. to the best in the business and may be able to direct you to the expert advise you require. You may mention my name Brian as your source.

  • My B12 readings are high and have increased since a test in 2014. I do have the symptoms of low B12 . Used to have injections 20 years ago. I have been advised to have Dr do MMA and actually due for retesting shortly so will make sure that is in there. There seems to be something with my liver they are watching also. I am tired of searching and trying so many herbal items to "make me feel better". My blood pressure was high as was my cholesterol but with no good reason.. I am not over weight don't drink or smoke :-( My Dad required B12 for some years.

  • Hiya undies80 I've still no answers :( ..looked back and have been having b12 injections since 2012 ..except had a year of none may 2015 to date ... Going GP weds to see what the bloods show ? After chatting on here with other members about b12 a few have said it takes years for the b12 to drop after having injections ? My results seem to be stuck at 2000 doesn't change at every blood test :( some people say there's is even higher ! Such a worry not knowing if it's just because of the injections or not ?? I haven't had MMA did homocysteine which was ok .. Keep me updated on how you are .. Take care Lynn xxxxx

  • Just an observation my recent labs came back high vitamin b12. Number there 2000 but it was explained to me that was not my number but where they stop counting . So my actual number is somewhere over 2000. My red blood was slightly high , white on the very top of normal . I have a myriad of symptoms too much to get into but fatigue is huge. The doctor likes to call it agoraphobia as I rarely leave me room. Most of my symptoms are neurological. But when I saw 2000 on so many posts I wondered if people realized they stop counting at that number. My GP says no such thing as too high Vitamin B and wasn't concerned at all. Internet says different but I have enough on my plate don't want to freak out about anything unnecessarily .

  • My GP says no such thing as too high Vitamin B and wasn't concerned at all. Internet says different

    GP correct.

    Internet, as is often the case, wrong.

    Not all assays top out at 2000. My B12 always comes back as 5999 - because that's where they stop counting.

  • Hi I've just found out I have pernicious anemia based on antibody tests, yet my b12 levels have been over 700 for years. Regarding the high b12, doctors haven't said anything... but my natrupath (who's also trained in immunology) said high levels in blood means cells are not absorbing it... so im actually deficient. Now the PA diagnosis... I'm hoping b12 injections would help?? Would I actually absorb the b12 this way (detouring the gut)? I really hope so!!

    I also have other autoimmune conditions like Hashimotos and Vitilago. I've spent the last few years battling with bacterial and viral issues like Lyme disease and Epstein Barr Virus and other Herpes strains.

    I'm in Australia so I don't I would be able to get help through the English medical contact people have been speaking of on here??

  • You will receive lots of good advice from the folk on the PAS forum and also the TUK one. Good idea to start a new thread as this post will easily be missed

    ..... 😊

  • Hi GeorgieInAustralia - I was wondering how you are doing? I've been suffering from a chronic unknown condition and consistently have elevated levels of B12. I was intrigued by your Naturopath being trained in immunology and that he/she said your cells aren't utilizing it despite the high number. Do you have an explanation or treatment plan?

  • Hi! I know this post is old but seeing if you've figured out more with this? I have Lyme too and Bartonella. My B12 is always high but I don't take vitamin B12. I'm wondering if not being able to absorb B12 could be part of Lyme or Bartonella? Lyme can also come from fleas and mosquitos. So many don't realize this and have Lyme and Bartonella but don't realize it. It took 12 years to have doctors finally figure it out and start treating it and I finally started feeling better. Bartonella also can cause neurological symptoms. Low B12 can effect the brain. It's just a thought. Anyway, I hope you're feeling better from the Lyme. I know what it's like. Boosting the immune system helps a lot of people I know with Lyme but the body can become super sensitive to things due to Lyme too.

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