Pernicious Anaemia Society
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B12 advice

I posted this in Thyroid Uk ( I'm newly diagnosed as having hypothyroidism). and was advised to post it here due to my B12 result. I was told by some posters, that although my doctor told me my B12 is normal, it is actually low. Any feedback would be gratefully received, thank you.

'TSH is still 5.85 (0.27 - 4.20) ( no change after 6 weeks of 25mcg levo) so my levo has been upped to 50mcg

Thyroid peroxidase ....8 Kiu/L Doctor tells me this is normal.

Free T3......4.6pmol/L. (2.8 - 7.1) Normal also

B12....232ng/L. (191 - 663). Normal

Serum (4.6 - 18.7). Normal

Doctor tells me I'm deficient in Vit D and has given me once a week doses of 2 vials for 6 weeks to take, he says this should sort it. the results were

25 - OH Vit D level. 34 nmol/L. >50

FSH was also tested on my request to see if I could put any symptoms down to menopause, again head the hormones were normal 16 iu/L which apparently means I'm not through to menopause.

Can I just confirm that the doctors ' normal' is what is actually deemed normal to sufferers?'

9 Replies

The serum B12 test is a poor guide to what is actually happening with significant numbers of people showing strong clinical symptoms of B12 whilst readings come back as normal range.

This is in part because the test is looking at all B12 and not just the active forms of B12 that are used by cells. It is also partly because normal is defined by averages without any reference to how much populations vary and people vary an awful lot when it comes to B12 ... there are similar problems with tests for thyroid. And finally it is also a poor guide because it just tells your doctor what is happening in your blood and not what is going on at the cell level.

Unfortunately most GPs and specialists just aren't aware of how important it is to look at clinical presentation not just at test results so it can be very difficult to get treatment.

Add to this the huge overlap of symptoms with other conditions, such as thyroid, and compound this with the general ignorance in the medical profession as to exactly what the range of symptoms of B12 deficiency are (many aren't aware of anything more than anaemia) and getting diagnosis starts to become a real up-hill battle ... and that is just the first as getting the right treatment for you may become a battle as well, especially in the UK where the treatment regime seems to be based on no valid scientific evidence that anyone seems able to produce - UK 3 months for maintenances, Germany 1 month ... and even 1 month is too little for some.

The standards agency for blood assays issued this alert in the UK a little while ago

The BCSH guidelines also highlight the need to treat on basis of symptoms not test results.

Your folate is close to bottom of the range. This can also be a problem as folate is needed to process the B12 that you do have. Important that if it does fall any further and you become deficient then you get treated for both B12 and folate not just for folate ... as treating folate can mask one of the symptoms of B12 deficiency (macrocytosis) causing further delays and the risk of permanent neurological damage once the neurological symptoms start.

B12 deficiency is caused by an absorption problem affecting the ileum (which is where 99% of B12 is absorbed. There are a number of potential causes - include lowering of acidity levels (generally as you get older), gastric surgery, auto-immune reactions that attack the absorption mechanism in the ileum (PA) and drug interactions (ironically including drugs that are used to treat potential symptoms of a developing B12 deficiency (including gastric problems).

Vitamin D deficiency is common with the absorption problems that cause B12

A B12 deficiency proper can take years to develop after absorption problems start as B12 is stored in large quantities in the liver and released through the ileum - a very efficient recycling mechanism under normal circumstances ... but once malabsorption takes hold the recycling mechanism is also broke so things tend to start snowballing.

Symptoms of B12D can be found here.



And you shall take dubbel amount of hormon. Your TSH optimal level is about 1.


If you don not have nevro or psyceatric feelings I don not advise you to start taking B12 yet. Instead do homosystein , MMA and holotranscobolamine first !


My symptoms are stiffness and aching body all over but more so in the legs/ hips. My memory is dreadful now and I'm constantly struggling to find the words I need. Along with the usual thyroid symptoms of weight gain and tiredness. I don't recognise homosystein, MMA or holotranscobolamine. What are they?


My stiffness in hips, legs and getting up from bed and chairs was cured by a dose of 5000iu of vitamin D3 Daily. I was found to be vitamin D deficient and was only given 1000iu by my Doctor, but by coincidence the 1000iu cured my stiffness, legs and bone pain, oddly almost overnight, but pains came back after a few days, so thanks to a member on Thyroid UK, I upped my Vitamin D3 to 5000iu, which I take daily, all pains come back if i forget to take my daily D3. I too had low grey area B12 bloods and have a thyroid problem now under control because I self dose my own sourced Natural Dessicated (pigs) Thyroid.

If I was still under my Doctor now, on the lower dose I would not be feeling well.


Oddly I took a dose of 50,000 IU Vit D on Saturday ( as prescribed by the doctor) and today I got out of bed with no stiffness/ pain for the first time in over a year! So I'm hoping that if I get on top of the Vitamin D it will sort me out! I'm quite excited!


Amazing stuff D3, I wonder how many of us are suffering stiffness, not knowing it is not down to just getting old. My Mum told me at the time I was getting old quick. :)

So pleased to hear it has worked so quick for you too. You need to keep taking the D3 once the Doctor's prescription has run out otherwise you could go back down hill with your symptoms.



This webpage has links to info on Homocysteine, MMA and transcobalamin (Active B12).



Have you had a ferritin test and a FBC test?

A FBC (Full Blood Count) can give clues as to whether a patient might have B12 deficiency. If MCH and MCV are high on the FBC it indicates the possibility of macrocytosis. See links below.

Low iron can make red blood cells smaller, low B12 and/or low folate can make red blood cells larger. if you have both conditions then red blood cells may appear to be "normal" size and a GP might miss problems.

Other tests that may help to establish if a patient has B12 deficiency are MMA, homocysteine, Active B12 and a blood smear. An IFA (Intrinsic Factor antibody) test can help to diagnose PA (Pernicious anaemia).The IFA test is not always reliable and a person with a negative result may still have PA.

Your B12 is at a level where some people are symptomatic for B12 deficiency even though it is within "normal range".

Have you looked at lists of B12 deficiency symptoms?


Symptoms Checklist

Recent documents/articles make it clear that people who are symptomatic for B12 deficiency should be treated even if B12 levels are "normal" range. See links below.

Google "BSCH Cobalamin and Folate Guidelines"

This document came out in 2014. Some GPs are unaware of it. I was told the NHS should be following it. I found page 29 a diagnosis flowchart useful. The PAS have a summary of this document in library section on website.

Useful websites


01656 769467

If you leave a message they will get back to you within a few days. They are helpful and sympathetic.

Useful Books

"What You Should Know About Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper

Martyn Hooper is the chair of the PAS and has written several books about PA and B12 deficiency.

"Could It Be B12" by Sally Pacholok and JJ.Stuart

A very comprehensive book about B12 deficiency.

Have you ever had a coeliac test?

Sadly autoimmune conditions sometimes come in clusters.

Gambit mentioned your folate being at the low end of the range.

Important info in Management section

I am not a medic, just a patient who has struggled to get a diagnosis and wants people to have the info they need.


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