Thyroid UK
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I thought I'd better post this as new message as I keep seeing people relying on their GP B12 blood test which is of little us because only 10-30% of serum B12 is actually available to our cells. B12 is vital to our health that it is everyone's interest to get the test above done if at all possible.

It's done at Guys, see link above (other private labs may be catching on now?) cost £18. The contact is, you need gp referral letter (my gp just stated I've been exhausted for ages - actually it's years!).

There is quite a bit of info on the internet on how B12 binds to what and why a lot of it is just expelled (in urine) from the body.

11 Replies


thanks for that. I asked my GP but he refused so not sure what to do. My B12 is 728 now so I don't think I can convince him! If I can find research papers to back this up then perhaps I might convince him for a referral!


The Pernicious Anaemia Society

has a lot of information re PA and B12 deficiency.

The PA Society posted on Pernicious Anaemia, Health Unlocked a notice that the Active B12 test is going to be rolled out to all Nuffield Hospitals in the country when we will be able to have an Active B12 test done without a GP's referral being needed. It is at referral

As one whose recorded low B12 was ignored by a contemptuous, angry GP, who had not even heard of MMA/homocysteine, and the fact you mention above that only 10-30% of the serum B12 is available to the cells, I applaud your efforts to tell as many people as possible the whole truth about B12 testing levels as currently established by the NHS.

Professors Smith and Refsum have done much research on this issue.


The link I gave still works but I better give it correctly:


At least you will be getting blood tests, compared to some GPs she is being open minded, though cursed with the widespread ignorance among medics when she says that 259 is OK. If you supplement sublingually to use mouth membrane absorption route avoiding the possibility of extant but undiagnosed PA/B12 deficiency from whatever cause, and down load Kevin Byrne's "The Enterohepatic Circulation of Vitamin B12" (Professional Version) explaining how it is necessary to achieve a higher concentration gradient of B12 outside the cells to ensure B12 getting into the cells, you will be very successful. Ensure your potassium is OK, eat a banana daily, use unrefined seasalt for minerals, get folate checked should be at least 3/4 up range.

There is basic info re irons in hypothyroidism in this link to trigger further researches - or requests for further more searching iron testing.

i wish you the success I had, stay well.


Thanks for replies peeps, it seems the message is getting around! So many people are missing this link, adjusting meds and supplemments to no avail. Part of the problem is lot of people are supplementing with B12 and so the GP test comes back within range which is low in the UK as well.


I did the test through Guys with a referral from my GP. I was unable to go there in person, so the lab agreed to send me a "postal kit". (Add a further £12 to the £18 fee)

This all worked out OK in the end, but it was a bit of a struggle as the people at Guys make no concession to the fact that they are dealing with members of the public and not other medics. The enclosed instructions therefore were fairly unintelligible.

My advice is to keep pestering Denise Oblein with questions - that way, the penny might drop and they might change the wording into something that actually tells you what to do!


if your gp refuses but you feel you are low on b12 just supplement it anyway and then you will feel better if it's low and not if it's not.far easier than waiting for a test


I believe injections intramuscular are need in certain cases this organisation shows a flow chart of symptoms and which protocol is needed.

I've only just found this but will be reading it thoroughly, I've been complaining of the same symptoms for years!!

the doctor who runs B21d seems very knowledgeable


Yes, he is knowledgeable, so much so he leaves the NHS far behind. So guess what? He has been hounded for his good work and successes just like Drs. P, M, and S, even forced in the past to stop his treatment of very ill people.

Witch burning might have gone out of fashion but we have our very own modern medical equivalent which still focuses on healers.


found this article !


My gp fobbed me off yesterday, I am waiting for gastric tests, she wanted to get those results before 'discussing' injections but to my mind even if I have celiacs, chrones or colitis all this does is confirm why I can't get B12 through my gut (I bet diagnosis will be IBS (cope out!) I am going to wait for active B12 test from Guys, due now, and go back to GP next week and insist on injections, otherwise I'll get them privately.

The bluddy endo at Guys as signed me off back to GP thought I am ten times more ill then when I first saw him - incredible!


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