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Can anyone help me regarding B12?

I've had a load of blood tests done privately - and I'm even more confused now than I was before. I'll be posting some more questions once I've got my head round it all, but I just wanted to see if anyone can help me with this query about vitamin B12.

As background, I was diagnosed with ME/chronic fatigue way back in 1999, and later - when I started to get a lot of join pain - with fibromyalgia and then polymyalgia too. I've since developed other symptoms such as severe constipation, very dry chapped skin, dry eyes, etc. I've been tested for lupus and sjogren's syndrome - and the docs say "no" to both of those. I seem to have all the symptoms of hypothyroidism - though all my thyroid blood tests come back fine (more on those in another post shortly).

I had wondered about B12 deficiency - but my results have come back as follows:

B12 - 777 ng/L (191 - 663)

So I'm actually *above* the highest level in the range! Here's what the doctor said about it in his report:

"The high level of Vitamin B12 is a good finding. B12 is well tolerated by the body, even in very high concentrations. Many experts believe that the lower limit is set too low and that many individuals are deficient despite being 'officially' in range. 500ng/l plus is possibly the target that should be aimed for. Anyway, your level appears fine."

I *think* this is the serum B12, not the active B12 test. Looking at it, it seems like I have plenty of B12 in my system, as the doc says. But then I read an article somewhere which said that if there is a high level of B12 in the blood this *may* mean that it's just building up there and not being utilised properly - hence, I might still actually be deficient in it. I suspect, though I'm not sure, that I might have a problem with malabsorbtion, since I'm always anaemic and have low vit D levels too. Can anyone help me shed light on this B12 reading please? I'm really confused about this now.

I am thinking I might try a sublingual B12 supplement anyway - just to see if it does seem to give me more energy - since I guess you can't take too much of it?

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hi yes your b12 is looking good ,your vitamin d if it is low vitamin d with calcium is very good .do you take any form of b12 or vitamin ? also b6 and b9 could also be ones to look at .a great book could it be b12 is amazing Good luck

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These papers may be of interest



My b12 is also elevated and I have many symptoms.


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I agree with Roslin, you can't use the serum B12 test to decide on whether or not you are B12 replete or deficient, it's a flawed test. You can have a functional deficiency at any serum level. If you've never supplemented you might want to consider Active B12, MMA or Homocysteine tests.


Thanks, guys, that's really helpful! No, I've not supplemented with B12. The GP wouldn't sanction injections when I tried before (and she certainly won't if she sees this test result!), so I'd have to try it myself.

I'll look into these tests you mention, Hampster, and also see how I could self-supplement if needs be. Am I right in thinking it would be sublingual B12 I'd need?


I'm not the right person to ask that question, as I don't rate the sublinguals over injectable B12, particularly if you have neuro symptoms. Also, type of B12 needed varies from person to person - Cyano, Hydroxo or Methyl. Methyl is not always right for everyone, but you will often see it plugged as the only option to go for. Trial and error is the name of the game.

Methyl subs certainly did nothing for me (I have Graves and PA). There are many people taking them that continue to deteriorate, but ruin their chances of proper diagnosis because blood levels stay normal. And there are others that respond very well to them. Just don't take them yet if you're thinking of further tests. See here:


Do you have an FBC? There might be some clues in there as to whether or not this is a problem for you. If you do take them, please also take a B-complex with all 8 B-vitamins to keep them in balance, and possibly some extra folate on top of that if you are low.

Also don't forget about magnesium, people with low vit D (picked up from your other post) often also have a cellular magnesium deficiency:



"Do you have a FBC?" - yes, but I haven't a clue what any of it means! Here are the FBC results:

WBC 5.3 x10^9/L (3.7 - 11.0)

RBC 3.87 x10^12/L (3.80 - 5.80)

Haemoglobin 118.0 g/L (120 - 150) +

HCT 0.35 ratio (0.36 -0.46)*

MCV 90.0 fL (81.0 - 95.0)

MCH 30.4 pg (26.0 - 31.0)

MCHC 337 g/L (315 - 345)

Platelets 325 x10^9/L (140 - 340)

RDW 11.2 (11.0 - 14.0)

MPV 7.4 fL

Neutrophils(Abs) 3.3 10^9/L (2.5 - 7.5)

Lymphocytes (Abs) 1.6 10^9/L (1.5 - 3.5)

Monocytes (Abs) 0.2 10^9/L (0.2 - 0.8)

Eosinophils (Abs) 0.1 10^9/L (0.02 - 0.7)

Basophils (Abs) 0.0 10^9/L (0.02 - 0.2)*

Neutrophils 61.9 % (40.0 - 70.0)

Lymphocytes 31.0 % (20 – 45)

Monocytes 4.6 % (2.0 - 10.0)

Eosinophils 2.2 % (1.0 - 6.0)

Basophils 0.3 % (0.1 - 1.0)


In your other question you say you have mild anaemia, and you can see that here with your reduced Haemoglobin, Haematocrit (HCT), RBC, and RDW. And we know that your iron tests were not great, so you've got some iron deficiency going on. In iron deficiency the red blood cells are small, called microcytic anaemia.

However, if it was just iron deficiency, then your MCV and MCH would be low end of the range too. But you can see that they're not. MCV is in the top half of the range, and MCH is at the top of the range. This points to the possibility of macrocytic anaemia, or enlarged red blood cells. This is seen in B12 and folate deficiency.

When you have both microcytic anaemia and macrocytic anaemia the MCV can appear to be normal, as in your case. It is a measure of the average size of your blood cells, so they cancel each other out.

MCH is a calculation of the amount of oxygen-carrying haemoglobin inside your red blood cells. Since macrocytic red blood cells are larger than either normal or microcytic red blood cells, they would also tend to have higher MCH values. You're at the top of the range, which is not what you would expect with iron anaemia.

Based on the above I would suspect a functional B12 or folate deficiency.


very interesting...I suspect I've a B12 deficiency so had a GP's test which was 'normal'. I've taken supps for years and also had a PEG test so know I have leaky gut. How and where would I get extensive and the correct tests? Si


The cheapest way is via St Thomas' hospital in London, but you need a GP referral letter. Active B12 £18, MMA £96, Homocysteine £40. Homocysteine has to be done at the hospital, the other 2 can be posted. Active B12 range is <25 deficient, 25-70 grey area, >70 replete. If in the grey area they will do the MMA test automatically. I'm not sure if they charge you the £96 in this scenario so best to ask. The person to speak to is Denise Oblein, details on this link:


If you've been supplementing, these tests can be normalised quite quickly, and it can take a long time to get them out of your system. St Thomas' recommend just 1 month off supplements, but I've seen something more like 4 months recommended over on the PAS forums. So might be a waste of money if done too soon after supplementing.

There are other places you can get these tests done privately, have a google around to compare prices.

Alternatively you could ask the GP to run the antibody tests, anti-intrinsic factor and anti-parietal cells. Positive results point to PA, but you can test negative and still be deficient. So it's one of those tests that's only clinically useful if positive.

More info on testing here:


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Meant to add something re Homocysteine. The top of the normal range at St Thomas' is 15, but a healthy Homocysteine level is actually around 7 or 8. You should certainly think about a good B-complex containing all 8 B vitamins if you're above 10. The important ones for lowering Homocysteine being B12, folate, B6 (not more than 60mg) and B2. Thorne Research have some good options.

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Wow, hampster, you're brilliant at all this. Do you have medical training? You seem extremely knowledgable on the subject.

Yes, B12 seems to be an issue for me for sure. Not sure about folate - I'll have to check the test results again and see what was said about that.

Thanks ever so much for your helpful posts! :-)


Gawd no, not medically trained, although I'm not sure most of our GP's are either ;-)

You have to know a lot about B12 to even get a diagnosis, let alone the best treatment, so it's read, read, then read some more. I help moderate the PAS forum so also used to looking at blood tests. There's usually iron anaemia in there which muddies the waters when trying to diagnose B12/folate deficiency.

Always remember there's no gold standard test, even with the ones I've discussed above. Therapeutic trial of B12 injections is the best course of action if symptomatic. Folate deficiency is almost always co-existing with B12 deficiency. Even if you're not folate deficient to start off with, taking B12 on it's own will deplete your stores pretty quickly.


And what do you think about methylfolate, hampster1? I have an Asperger's son with low ferritin and iron, won't do blood tests, or injections, tried him on methylB12 sublingual for a bit, seemed to help a little with eye contact and less touch sensitivity but hard to be sure, then I added in methylfolate and wow! almost immediate transformation of mood from depression to cheerfulness. I suspect a MTHFR genetic flaw, and/or autoimmune problems with folate receptors, both of which have been found in higheer level than normal in autism. He has high free T3 - or did have the only time I got a blood test out of him.


I would suspect MTHFR too from what you say. Have you had a read around mthfr.net/? Also good is Dr Yasko dramyyasko.com/

There's no question in my mind that if you take B12 or folate you must take them together, and dosage is very individual.

I know that with taking folic acid there is concerns about UMFA (unmetabolised folic acid) which is why methylfolate is considered better. But there seems to be a quirk whereby some people just can't tolerate methylfolate, or alternatively it does nothing for them, and so they have to stick with folic acid. It's trial and error.


For many labs, the upper limits range can go up to 850 when 800 is considered an optimal level. Your levels are on the good side but not alarmingly high.

In many countries of Europe and in Japan, too, any levels below 500 are considered deficient and require supplementations.


As for your anaemia, did they check your ferritin levels, ferritin saturation, folate?

For a molecule a blood to be formed it needs, iron, folate, and b12.

Low levels of D is a consequence of low ferritin as D intake needs iron to be synthesised


Thanks, Melanie. That's interesting about the different ranges they use at different labs - and even in different countries. In fact, I've now had an *active* B12 test through Blue Horizons and I'm awaiting the result. I've also started supplementing with a B12 sublingual spray.

Re the anaemia, I can't recall offhand what's been checked, but from what I recall it certainly does look like B12 and folate might be the problem here (or one of my problems, anyway).

Thanks a lot for your input. I find all this medical stuff really complex so it's great to find people here who know about this things and can explain them to me. :-)


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