Serum B12 level question: Having read some recent... - Thyroid UK

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Serum B12 level question

DandyButch profile image
12 Replies

Having read some recent posts regarding B12, I checked my last results.In May 2022 my serum B12 blood test result was 345ng/L range 180-999

I started supplementing liquid B12 around Xmas 2023 .

In April 2024 my serum B12 blood test result was 1952ng/L range 180-999.

Following the last result, my GP said to stop supplementing.

However, I am now concerned whether that was the right decision. Particularly when people on this forum describe the difference between Serum and Active B12.

Is anyone more knowledgeable than me about this?

Please can anyone help?

Thankyou

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DandyButch
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12 Replies
Jaydee1507 profile image
Jaydee1507Administrator

GPs often seem to be concerned with an over range B12 level. They have no training in nutrition and dont realise that its of no significance at all and does no harm.

Suggest you restart your B12supplement and ignore GP comment.

DandyButch profile image
DandyButch in reply toJaydee1507

Thankyou. I have definitely noticed a decline in my whole self, so wondered if this could be relevant. Which seems to be.

iI had a similar situation a year ago, I stopped supplementing and within six months my B12 had plummeted to almost bottom of range. I’ve now restarted the B Complex on the advice of another GP who reminded me of what I should have known: any B12 test taken while supplementing will give a result which has no resemblance to your actual B12 levels.

DandyButch profile image
DandyButch in reply to

Thanks. I have definitely noticed a gradual decline in my health, and am trying to find cause. Seems like I have.

in reply toDandyButch

Yes. Me too. I seem to have every symptom of B12 deficiency. The irony is that the B complex I’ve taken all my life is now upsetting my stomach!

Grrrr

humanbean profile image
humanbean

I distrust and ignore the reference ranges for B12. I always try to keep my B12 level at around 1000 ng/L and I don't care if it goes over. I do care if it drops much below that.

Another thing I do is make sure I only ever take methylcobalamin or adenosylcobalamin. I only take the adenosyl-B12 occasionally.

I had in the past taken cyanocobalamin but it never did anything for me. I found when I started taking the methyl-B12 that it actually made some of my problems worse for a few weeks but then they improved and have only come back if I stop supplementing.

Before I took methyl-B12 I had suffered from eczema for decades. It doesn't come back as long as I'm supplementing regularly.

I also developed spots on my face at puberty, like so many people do, but mine never went away, although they did diminish slightly in numbers and severity. After starting the methyl-B12 the spots briefly got worse than usual then disappeared completely. They only come back if I stop supplementing.

Some info you might find of interest :

perniciousanemia.org/b12/fo...

perniciousanemia.org/b12/le...

perniciousanemia.org/b12/le...

I've had both Serum B12 and Active B12 measured a few times, and in my case, if either of those is high then so is the other one. So, I don't particularly worry too much about which one I test. Obviously I can't say if this would be true for others.

I have found that stopping supplementing Methyl-B12 leads to my levels dropping quite dramatically, but I've never had a catastrophically low result.

DandyButch profile image
DandyButch in reply tohumanbean

Thankyou. I think I have found the cause of my declining health. Not that I was great before, just worse. SlowDragon gives a different view on B12. Who is right?Confused.

humanbean profile image
humanbean in reply toDandyButch

How people feel taking any kind of supplement is not likely to be the same for everyone and I think people just need to try them and see what happens. At least people need vitamins and minerals for good health. I've never heard of anyone having a statin deficiency.

Incidentally, the penultimate paragraph in this blog post from Malcolm Kendrick :

drmalcolmkendrick.org/2017/...

says this about the B12 ranges :

My view. I do not think the RDAs for vitamins are remotely accurate, or useful. They were established in times of absolute deficiency. The agreed Vitamin B12 levels, for example, were based on seven people, over sixty years ago, and remain unchanged to this day. All seven had pernicious anaemia (caused by vitamin B12 deficiency).

I've tried to find the source of that info but have never managed to find it. I could email Dr Kendrick and ask but have never done so.

I would have questions about how other reference ranges for vitamins and minerals were established too, but haven't looked into the subject.

DandyButch profile image
DandyButch in reply tohumanbean

There we go again. 'Fact based research' from the day of the dinosaur, with a handful of test subjects. What exactly does the Health Service do? The government keep saying prevention is better than cure, and ban or tax or demonise things when the cause is the useless testing parameters used to deny people the treatment, which is easier and cheaper than the damage to one's health further down the line and the eventual costs.Why, oh why don't they review the whole range thing completely. Not "normal" or "abnormal ", but, depending on individual health issues, could be abnormal in combination due to underlying health. Where is the 'of concern'. Everyone just gets told to eat healthier and exercise. What about people who already do this?

Sorry, on a rant again.

I just get so angry with the way the NHS is operating. In 2024, things should be better, not worse. Maybe too much money goes into other treatments so not enough left for basic healthcare.

SlowDragon profile image
SlowDragonAdministrator

Are you also taking a daily vitamin B complex and testing folate levels

Now your serum B12 is over 500 (or Active B12 level has reached 70), you may be able to reduce then stop the B12 and just carry on with the B Complex.

If Vegetarian or vegan likely to need ongoing separate B12 few times a week

B12 range in U.K. is too wide

Interesting that in this research B12 below 400 is considered inadequate

healthunlocked.com/thyroidu...

supplementing a good quality daily vitamin B complex, one with folate in (not folic acid)

This can help keep all B vitamins in balance and will help maintain B12 levels too

Difference between folate and folic acid

healthline.com/nutrition/fo...

B vitamins best taken after breakfast

Igennus B complex popular option. Nice small tablets. Most people only find they need one per day. But a few people find it’s not high enough dose

Post discussing different B complex

healthunlocked.com/thyroidu...

Thorne Basic B recommended vitamin B complex that contains folate, but they are large capsules. (You can tip powder out if can’t swallow capsule) Thorne can be difficult to find at reasonable price, should be around £20-£25. iherb.com often have in stock. Or try ebay

IMPORTANT......If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 5-7 days before ALL BLOOD TESTS , as biotin can falsely affect test results

endo.confex.com/endo/2016en...

endocrinenews.endocrine.org...

In week before blood test, when you stop vitamin B complex, you might want to consider taking a separate folate supplement (eg Jarrow methyl folate 400mcg) and take separate B12

Post discussing how biotin can affect test results

healthunlocked.com/thyroidu...

helvella.blogspot.com/p/hel...

DandyButch profile image
DandyButch in reply toSlowDragon

Thankyou.I take Thorne basic vitamin B complex, and yes I stopped it over 7 days before blood test.

I did not have active B12 tested, only serum B12.

And no not vegetarian or vegan.

Dancer57 profile image
Dancer57

An Active B12 test will given an indication if you are absorbing B12 at cellular level if that is what you want to know.

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