Pernicious Anaemia Society
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Hi There

My friends on Thyroid Uk Healthunlocked have pointed me in this direction as my B12 is low.

Vitamin B12, 244 142 - 725 pmol/L

Intrinsic Factor Antibodies 4.2 0-10 U/ml

Red Cell Folate 1183 158-1099 mml/L

I have Hashimoto's and I am not started supplementing B12 in any form.

I am assuming that I don't have PA and it is not worth consulting my NHS GP and that I should try to raise my B12 on my own.

Before I start, is there any further tests I should have, or generally, how should I proceed.

Your help is very much appreciated

7 Replies

It all depends why you want to raise your B12, what symptoms you may have and if you can raise your B12. Your RBC folate seems high, so best not add to that. You can try over the counter B12 tablets, health food shop do them. It all depends if you have an absorption problem with vit B12 what you would need to use to raise your B12, but it is not that low, although the active B12 test would be a much better test to have, see:


Are you taking any kind of multivit or eating Marmite?


a) the IFA test is known to be insensitive with the result that there is a 50% chance that you do actually have problems when the test comes back saying that you don't.

b) what matters with B12 deficiency is really the symptoms so would be best to have a look at what those are which can be difficult as they overlap with other conditions.

c) unless you are absolutely sure that your B12 is low because you don't have much in your diet, falling B12 levels are indicative of an absorption problem.

d) about 1% of B12 is absorbed 'passively' ie not through specialised cells in the ileum so flooding the gut with B12 can help.

e) however, if you have an absorption problem that is likely to mean that your ability to recycle and reuse B12 stored in your liver is likely to be compromised.

f) PA isn't the only potential cause of malabsorption. As you get older your stomach acidity tends to drop and this can inhibit absorption. There are also drug interactions - including some anti-acids, some diabetes medications (metformin), some pain killers etc that can affect absorption.

Gastric surgery affecting the ileum is also another obvious cause.

unless you are absolutely certain that your GP isn't going to listen it would be best to talk to them first rather than go for supplementation.

People vary very much if they do have an absorption problem in how much B12 they need and what types of B12 and methods of delivery work for them.

As Marre says you can buy tablets over the counter. You can also get sublingual sprays, nasal sprays and skin patches.

You can't overdose on B12 and there aren't any known down-sides to having high levels of B12.

You can go for cyanocobalamin, hydroxocobalamin and methylcobalamin ... and others but those are the most common forms. most seem to find that methyl works best if they have neurological symptoms but it isn't always the case.

In terms of diet fish and dairy seem to provide the most easily absorbed forms of B12.

You need to have good folate levels to be able to absorb and utilise B12 so worth getting your folate levels checked and/or looking at supplementing that.

High levels of folate can mask the development of anaemia which is one of the symptoms of B12 deficiency but otherwise no reported downsides.

If you go for a B complex advisable to watch the amount of B6 you are taking in as high levels of artificial B6 (100mg+ over months) can cause neurological problems. They generally reverse when supplementation stops - but there are some reports of the effects being permanent.


Thanks for your replies

I am 50 years, my diet is really good with lots of fish, dairy and meat protein. I am not supplementing at all. I have been taking Low Dose Naltrexone, which has lowered my Thyroid antibodies from 800 to 80 but stopped thus a month before the IF test.

I am symptomatic:

Pins and needles/numbness in little fingers/forearm on waking




All the above I have had for 15 years and have not improved with thyroid treatment over the same period.

I am not taking any medication that could hamper absorption.

I will talk to my NHS GP but do feel I need to back myself up with something concrete or I will just be dismissed.

Thanks again


Hi Tango2 ,

I suggest printing out these 2 links below (read it and give a copy to GP), ask to have the active B12 test as Serum B12 test is not very useful and new guidance is to test further with serum B12 in the so called grey area , tests such as active B12 and or MMA etc 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."

I hope this helps,

Kind regards,





Thank you


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