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Vitamin B12 and Folate blood results, advice please


Diagnosed Hypo 2.5 years ago on 50mcg levo for 15 months increased to 75mcg for 8 months and now

I have been taking 100mcg since May and just increase to 125mcg 12 days ago.

I have just received my blood results from Myrios 18th Sept.

Vitamin B12 904 pmol/L Range 141 - 489

Folate 45.4 nmol/L Range 10.4 - 42.4

Test at G.P. 26th March

Vitamin B12 377 ng/L Range 180 - 1130

Folate 5.3 ug/L Range 3.00 - 20.00

Since then I have been supplementing with a sublingual spray 2400ug daily.

Obviously the B12 spray has put my levels up but would it have also put my Folate up that high

I have not been supplementing with folate only the B12

Should I stop supplementing or just reduced the B12 spray and is it dangerous for the Folate to be that high.

Any advice would be greatly appreciated.

Many thanks browny

11 Replies

...I have read that you have to stop the b12 before testing. The length of time has been debated on here I believe. A week was the least amount of time. Take a look at b12d.org Maybe it skews the result if you take it right to the line....


Thanks Marz


That's interesting. How do you feel?


Pretty much the same, still tired, new sypmtoms of tingling on face with numb feeling sometimes, which have only been happening for about 3 weeks. I am concerned why the Folate has risen so much.


Only 2 things come to mind based on my limited experience. Firstly, have you changed your diet? Serum folate is very responsive to dietary increases and decreases. A better measure of long term folate status is red cell folate.

The second thing that comes to mind is the folate trap, link here:


A good test for folate trapping/methylation defects would be homocysteine:


Some people respond better to hydroxocobalamin B12, depending on what genetic defects are at play. You could try switching to this and see what happens? Someone on the PAS forum has had good results with this one which is a patch:


Or there are sublinguals (which I've never tried):



Or a nasal spray (which I have tried, didn't work for me):


Lots of options, you need to experiment.

H x


Meant to mention iron. Vital to have good levels.


Thanks for all the links I have had a quick look at them but I will have to read and reread them as quite a lot to take in. Do you know if there is a problem with the high Folate levels, also when GP did blood tests Iron results was not mentioned but she said Ferritin was 88


It's not that high really Browny. If you convert yours to ug/L then its about 20, which is top of the range on your first folate test. My understanding is that very high folate can be a problem if you are over-supplementing, but if it's high naturally then that's usually a transient dietary fluctuation or a sign of B12 deficiency (folate trapping). That's why I wondered if the B12 you were taking was not getting where it needed to go, and perhaps trying a different one might help.

Did you have any reaction at all to the spray when you very first took it, good or bad? You could switch to the Jarrows sublinguals if you wanted to stick with Methyl, they might work better for you. Or you could have a break from it and see if you feel better / worse. B12 and folate deficiency symptoms are very similar, so weirdly the answer might lie in actually adding in a folate supplement alongside the B12. I take a B-Complex with the most active forms of B12 and folate in it and that works very well for me. And it's not a super high dose of folate, 400mcg which is the standard RDA. Pure Encapsulations is the one I take:


I used to take Jarrows B-Right, but read that although it claims to contain active folate the majority of its folate is actually just bog standard folic acid. I took folic acid for 3 or 4 months to correct my deficiency, but now I don't want it building up anymore so just take my B-Complex.

Your ferritin level is spot on.

H x


Hi Hampster

I have not changed my diet at all and I did not have any reaction to the B12 spray. I have read the link re Folate but its a bit difficult for me to understand. Does it mean the B12 is not getting used properly and also increasing the Folate level. If I supplement with Folate will this not increase it still higher and if it did would it cause problems?

Many thanks browny


I just don't really understand enough of it myself to give a good answer, and there are no easy explanations of it online that I can find. Try this link from the phoenix rising forum:


Ultimately what I'm trying to say is you still might not have enough B12 going in, or the right type of B12 going in for you.

You say you noticed no change in symptoms from the B12 spray? Perhaps you should stop taking it and see what happens. You might be surprised that it is actually doing something after all.

Or perhaps you could switch to a Jarrows 5000mcg sublingual and see if that's more effective for you?

Or perhaps you just don't need it at all, or you need hydroxo instead. Trial and error I'm afraid is the name of the game.

Here is a good article about folate that might put your mind at rest regarding safety of your levels:


I'm sorry if I've confused issues, still trying to get to grips with it all myself.

H x



Don't be sorry, if I am confused that's just me, it doesn't take a lot to confuse me nowadays. I really appreciate

all your comments and links. I understand the folate link and it has put my mind at rest.

Many thanks for all your replies.

Take Care browny

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