Pernicious Anaemia Society
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Advice of B12 levels

Hi there, I have come from the Thyroid Uk site, after suffering with symptoms of exhaustion, excessive thirst, brain fog (I can forget what I'm saying as I'm speaking), dry itchy skin...eyes and everywhere else!, mood swings, foot cramps at night, blurred vision (I have to blink lots to restore clarity).... for over 10 months. My gp arranged a blood test in August '14 but as they all came back in range nothing happened. I went back to the Gp early Feb '15 to be told (without even listening to my symptoms) that as my bloods were all 'normal', I'd just have to live with it. Well I've not given up yet and I'm determined to get to the bottom of it with or without a GP!!

I've posted my results below and ask your advice. It was suggested by Thyroid UK members that the VitB12, ferritin and folate were all too low really and ought to be supplemented.

I am seeing a different Gp this afternoon and was going to ask what his opinion of the results are but I'm not holding much hope. They were all useless what I had viral thyroiditis a couple of years ago, kept telling me my symptoms were all in my head when in fact I was massively hyperthyroid....duh!

First results from 11/08/14 second from 20/02/15 range in brackets.

Serum Vit b 12 - 327 220 (115-1000)

Ferritin - 23 33 (15-300)

Foliate - 11.4 4.4 (<3 deficient )

Glucose - 6.1 (3.6-6.0) ignored coz not fasting. not done second time.

HbA1c - 32 31

No Vit d results.

Thanks in advance

BTW I am 33 y/o female on asthma medications and nothing else

10 Replies


Your serum B12 is dropping , I'd ask GP for a request letter to have the active B12 test done at St Thomas's, it will be a far better test than the serum B12 test and should only cost £18,-. For more info see:

For info an active B12 test at St Thomas see:

Nutristasis Unit at St Thomas' St Thomas' Hospital North Wing - 4th Floor Westminster Bridge Road London SE1 7EH Telephone:02071886815 / 89543

Info about active B12 (holotranscobalamin) test, why etc, also good to give a copy to your GP, see:

This case study may help you see:

"B12 deficiency caused by hypothyroidism?

Patient SE, an 87 year old man, presented with shortness of breath and anaemia.

Hb was low, MCV was normal and TSH was elevated indicating hypothyroidism.

Total B12 level was 170pmol/L indicating sufficiency.

Normal RBC folate and serum folate indicated that Iron status was normal and the anaemia was presumed to be due to the hypothyroidism.

However, the Active-B12 concentration was only 4pmol/L indicating severe B12 deficiency.


Although the Total B12 level was normal, the Active-B12 level was severely low showing that the patient was B12 deficienct. Hypothyroidism patients can have this discrepancy between Total and Active B12 levels."

You may find reading the new British Society for Haematology Guidelines for the diagnosis and treatment of Cobalamin and Folate disorders helpful see:

"Summary of key recommendations

 The clinical picture is the most important factor in assessing the significance of test results assessing cobalamin status since there is no ‘gold standard’ test to define deficiency.

 Serum cobalamin remains the first line test currently, with additional second line plasma methylmalonic acid to help clarify uncertainties of underlying biochemical/functional deficiencies. Serum holotranscobalamin has the potential as a first line test, but an indeterminate ‘grey area’ may still exist. Plasma homocysteine may be helpful as a second line test, but is less specific than methylmalonic acid. The availability of these second-line tests is currently limited.

 Definitive cut-off points to define clinical and subclinical deficiency states are not possible, given the variety of methodologies used and technical issues, and local reference ranges should be established.

 In the presence of discordance between the test result and strong clinical features of deficiency, treatment should not be delayed to avoid neurological impairment.

 Treatment of cobalamin deficiency is recommended in line with the British National Formulary. Oral therapy may be suitable and acceptable provided appropriate doses are taken and compliance is not an issue.

 Serum folate offers equivalent diagnostic capability to red cell folate and is the first line test of choice to assess folate status."

It will help so much in the future if you now get a proper diagnosis, so you then get the right treatment you may need,

I hope this helps you,

Kind regards,


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Thank you for your advice marre. I will see what he says


Your folate level also looks as if it is getting very low. You need folate to metabolise B12

Hope the appointment went well.

the NICE guidelines (though a little confusing as it seems to be focused on anaemia but shouldn't be) do clearly state that there are problems with interpreting the B12 serum test and clinical signals are important in diagnosis.

Really hope that your appointment went well and the new GP is more clued up

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Oh dear, seems they know nothing.

He said my b12 levels are fine and that if I were deficient, my red blood cells would be larger than normal which they aren't. The only thing he said was a little low was my ferritin. I knew when he said all of this that I had no chance.

When I said would supplementation be beneficial he said I'd be wasting my money as if it did work it would be through a placebo effect and nothing else.

So stuff the medical profession, I'm going it alone!


Hi upset ,

I'm not surprised at you having an upsetting appointment, perhaps try to have one more appointment trying to explain to your GP:

Your blood cells (MCV) would be to large if you had and or B12 def and or Folate def, but as your ferritin (ferritine is stored iron) is on the low side this would be able to mask the blood markers of B12/Folate def as iron def would result in to small blood cells. If you are def in all 3 (or 2, one being iron) then your blood cells could be normal size.




"•The MCV may be normal if there is associated iron deficiency."

But it very difficult to tell a GP something he/she should know..all rather difficult. Wishing you a lot of good luck!

Kind regards,


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Thanks marre, yes I had remembered reading that cell size isn't an absolute indicator hence how I knew he was talking rubbish, but I didn't think he was going to take kindly to being told he was wrong! Plus i'm not very good at confrontation/questioning people ;-(

Short of trying another gp in the practice I don't think I'm going to get anywhere, but they're already going to think I'm a hypochondriac. Maybe try medicating myself and if it does the trick go to another of the doctors and say 'ha told you so !!!' A repeat blood test would then prove it wasn't down to placebo.

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Can so relate.

My suggestion for the future would be to

- keep a copy of the blood tests results you have had

- complete a checklist of symptoms that you have at the moment.

You can find a list here


Then may be if you ever do manage to find a GP that is up on B12 you can trot them out and may be get a proper diagnosis

It is so frustrating to come across GPs that think B12 deficiency is a form of anaemia rather than that anaemia is a potential symptom of a B12 deficiency (and ultimately would be a consequence of leaving it un-treated). Unfortunately it isn't a rare instance.

Its also so frustrating how GPs really don't understand the placebo affect and it's medical significance and trot it out as a way of dismissing people.

Your options in terms of supplementation of B12 aren't just sourcing ampoules and finding out how to do injections - you can try high strength sublingual tablets, sublingual sprays, nasal sprays and skin patches.

If you decide that you want to jump straight to injecting then there are two ways of doing it (actually 3 but ...) which is intramuscular (and you really need someone to show you how to do that) or subcutaneous (you can use insulin needles and there are plenty of you-tube clips to show you how). Subcutaneous doesn't quite get as much in to you and doesn't necessarily last as long.

You also have a choice of cyanocobalamin, hydroxocobalamin and methylcobalamin. People find that different ones suit them better or that some symptoms may respond better to different formats - I use a mix of hydroxo and methyl as hydroxo works best for me with the neuro-psychiatric and methly for the neuro (eg having a foot at the bottom of left leg rather than a lump of meat!). I find nasal spray works well for me.

If you can bear it it is probably worth going back to doc occasionally as symptoms of B12D have a large overlap with other conditions (hence high incidence of mis-diagnosis) and actually having one problem doesn't actually rule out another being present.


Yes gambit I've realised that you have to become your own expert with many medical things. My sister has to travel to geta good nhs consultant that can deal with her lupus as the local ones are clueless.

Your suggestion is good and that's what I'm thinking, self medicate then if symptoms improve go back and say told you so and get repeat bloods to prove it wasn't placebo. If it doesn't work ....well I'll cross that bridge wheni get there!

How soon would I expect to see improvement? I'm thinking tablets first and take it from there. Would be happy injecting but only if nothing else worked first.

Thanks again

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Once you start supplementing for yourself things actually get quite complicated in terms of meaningful testing - you would need to stop supplementing for several months to be sure that the B12 supplementation had got out of your system (somewhere between 3 and 6 - possibly more) and that would mean letting all your symptoms come back - not a road that many feel they can travel so please be aware of that.

It's not really possible to say how long it would take to see improvement though a lot of people do see some improvement in symptoms within a few weeks but it does vary very much from person to person and in terms of the energy it isn't uncommon for it to take 6 months or more.

B12 isn't toxic and there are no known downside to having high levels so there is room to experiment.

As said before your B9 is low so you really need to get that up or you probably won't seem much effect from the B12 at all.

Just googled B12 and asthma and came across the following which includes reference to asthma being treated with B12 - though it does say that the outcome of studies was inconclusive

also there's mention that some people with asthma also have low acidity levels in their stomach/gut, which is one thing that can lead to a B12 absorption problem and hence to a B12 deficiency.

Really sad that your GPs aren't prepared to look more at things - sort of makes you wonder how many other people with asthma are suffering unnecessarily.

There are some books that you might find useful - Could it be B12? by Sally Pachalok and 'Anaemia: the Forgotten Disease' by Martyn Hooper.

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Go to a homapatic Rx and have them compound u some iodione it's for thyroid tell him ur numbers Dr's haven't been correct for these numbers ever I live in a amarillo and go to west Texas pharmacy he's gteat


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