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
Written by
DandyButch
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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.
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.
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.
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.
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
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
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