Pernicious Anaemia Society
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B12 Levels

Hi all,

I have recently been diagnosed with 'marginally' low B12 levels at around 147. The Doctor told me the acceptable level was 150. However, I am suffering. Light heads and dizziness; tingling in hands and feet and more recently lethargy. The Doctor told me my level was not low enough to warrant injections and to 'eat more omelettes'! As I am allergic to eggs I started to take B12 Jarrow supplements but the symptoms have persisted and actually got worse earlier this week. I returned to Doctor today and he said he thinks I have acute anxiety. I am pretty sure I do not and told him so and he, reluctantly, revisited the issue of my B12 levels and has given me a B12 injection and taken bloods to test my absorption levels. I have to confess to feeling a tad confused!

Can I ask if 147 is marginally low?

And what would people recommend I do if the results come back okay but the symptoms persist?

Many thanks...


11 Replies


The BCSH haematology guidelines state treatment by injection should be given for levels below 200ng/l so your levels are low not just marginally low. Go back to your GP with someone you trust and a copy of the guidelines. You have symptoms so need treatment. Min loading doses alternate days until no further improvement if neuro symptoms and 3 times per week for 2 weeks if anaemic, followed by maintenance 2 monthly if neuro symptoms and 3 monthly if anaemic. Don't get fobbed off.


The guidelines and a recent BMJ Review and a lab assay alert all say to treat if symptomatic even if levels are normal as poor test so you definitely need to pursue getting proper treatment. If your antibodies come back normal then classed as intrinsic factor negative as only 50%sensitive test. Not a reason to stop treatment. If symptomatic response treatment should continue. Good luck!

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I did get my first injection today but was told to arrange to come back for two further injections next week. I have to call to discuss blood results tomorrow so will mention this then.


Sounds like your dr is marginal. Low is low. You need injections. Neurological damage is too important to faf about.


As per others your results are not marginally low they are LOW.

There are well established problems with using serum B12 to determine if you are B12 deficient

Significant numbers of people show strong clinical signs of B12 even when their results come back 'normal'

- which is why BCSH guidelines are to treat on the basis of symptoms and not test results.

In Japan you would be treated if your level was below 500 and you were showing symptoms.

It sounds as if your doctor really doesn't know much at all about B12 or he would realise that anxiety is actually a potential symptom of B12 deficiency

eggs tend not to feature very high on the list of good foods to eat for B12 - not sure if it is the white or the yolk but one contains a chemical that inhibits the uptake of B12 - best foods would be dairy and fish.

B12 deficiency is often associated with food intolerances and digestive problems - not surprising given that it is generally caused by an absorption problem

... all round they are in serious danger of scoring 'null point'.

Definitely take someone else along to help you and argue your case.

You could also try taking along a checklist of symptoms with all of those that apply to you ticked off.

You can find a checklist here


Unfortunately your GPs lack of knowledge is more the norm than the exception - so, don't get confused just because they don't have a clue.

Not sure what the blood tests were for - if it was for IF Antibody test then not a good test - don't really seem to be any definitive tests where B12 deficiency is concerned.

Really hope that you continue to get the injections you need.




Hello Elizabeth. Everyone here has given good advice and 'Frustration' s experience, as well as my relative's (left with permanent memory loss) highlights how serious the consequences are if not treated urgently.

Here are extracts from the book, "Could it be B12? :

"we believe that the 'normal' serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiencies begin to appear in the cerebrospinal fluid below 550".

"For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml."

BCSH, UKNEQAS and NICE guidelines, all recommend treating neurological symptoms urgently regardless of tests UNTIL NO FURTHER IMPROVEMENT and many GPs are ignoring them or not aware of them!

Your GP is obviously also not aware that acute anxiety is one of the important symptoms of B12 deficiency.

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I read that levels below 500 often result in neurological effects that cannot always be reversed. You have really low B12 and should be treated.

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Many GPs lack knowledge in this area it seems. The main problem is that the test offered to measure B12 levels is not an accurate indicator of deficiency. Total serum B12 is measured. Total serum B12 consusts of transxobalamin I (TCI) and transcobalamin II (TCII). Only TCII can be used by the cell as a cofactor in nucletide synthesis. Therefore it is possible to have a B12 result within the normal range but still to be deficient. This is because a high TCI level can bring the total B12 level into normal range, masking a deficiency in TCII. The BCSH guidelines for B12 are very out of date and in desperate need of review. The problem is likely to improve and make it easier for GPs when an assay is routinely used to measure TCII as opposed to total serum B12. A company called Axis Shield are currently developing this assay and it is currently being measured in some other European countries. The UK will no doubt follow suit in due course.

If you have a toal B12 level of 147 this would suggest a definite deficiency to me. You should insist that your GP sends samples off for testing for both Intrinsic factor antibodies and Parietal cell antibodies, to determine the cause of tour deficiency. He should also start you in an immediate treatment regime with B12 injections.

Current injections that are offered for treatment are hydroxycobalamin. It is possible to get Methylcobalamin injections privately by one Dr in the UK. Methylcobalamin is the form of B12 used by the cell in nucletide synthesis.


My b12 was 140 with low folate as well I was started on injections straight away, firstly loading shots then onto monthly then was put onto three monthly because my b12 was high !


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