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Low folic acid in RBC, very high B12 in serum


Senior Member
I'd like to get back on methylation so i've done some basic testing of B12 and folic acid in serum and RBC.
As suspected folic acid in RBC is deficient and lowish in serum. I've not really been supplementing with methylfolate except on the B12 injection days because it makes me feel sick, no matter how low the dosage is.
B12 is higher than the max. measurable level of 2000. I've been trying to get my folate needs from vegetables but clearly that has not been sufficient, the fact that i suffer from inflammatory bowel disease and malabsorption doesn't help either.

What i'd like to know is
What blocks the transport from serum to RBC? Am i lacking cofactors?
Does supplementing with hydroxyB12 deplete the folic acid even further?
I know these are basic questions but i currently don't have the time or motivation to read up on methylation, i'm hoping some of you with more knowledge on methylation would like to chime in.

Folic acid in RBC: 168 (reference range = 221 - 1113)
Folic acid in serum: 6.76 (reference range = 5 - 24)
B12 in serum: >2000 (reference range = 190 - 771)

BHMT-02 , 04 and 08
VDR Bsm + taq

Supplements used related to methylation for the past 2 years:
Hydroxycobalamin I.M. 10000mcg 2 X weekly, but lately more like once every 2 weeks.
Methylfolate solgar, 100mcg - 200mcg 2 X weekly together with the B12 injection


Senior Member
Vitamin B2 plays an important role in the folate cycle... so you may want to check that, and in general it would be best to support the whole B vitamins group with a multi-B, even at RDA doses. No need to megadose, especially when starting.

I've noticed that my issues with both methyl-B12 and methylfolate started to fade when I finally introduced all the components of the B group.

It has taken me a long time (over a year and 1/2) to build my dose from super low to a decent level, so patience may be in order.

For example if you can only tolerate, say, 50mcg of methylfolate start with that and don't push it. Let your body do its things (adjust, get used to it, startup... whatever) and then in a few weeks you might be able to add a bit more.

Contrary to some belief I have also used regular folic acid and folinic acid without ill consequences, so you may want to experiment with those too, especially folinic acid while folic acid is probably okay as a last resort, if both methylfolate and folinic don't work for you.

good luck


Senior Member
@PeterPositive, yes i was thinking about starting a multivitamin with 100% to max. 200% RDA, or just simply a b-complex with the active metabolites but i've not found one that's close to 100% RDA. Besides that, i've tried many b-complexes and they all make me wired. B2 hurts my intestines a bit, maybe i'll just have to start with the lowest dose possible. 25% RDA or something.

I don't tolerate 50mcg methylfolate more than 3 days of use. I have noticed though that the glucosamine bound one gives me less problems, it's the calcium one that makes me feel so sick.
I also have folinic acid and that causes no problem and neither does folic acid.
Strange that folic acid doesn't give you symptoms, i see you are +/+ for MTHFR C677T.
Perhaps the genetics mutations are not so important after all.
i was thinking about starting a multivitamin with 100% to max. 200% RDA, or just simply a b-complex with the active metabolites but i've not found one that's close to 100% RDA.
Jarrow's B-right has 100% of the folate RDA, and now entirely as methylfolate. Some of the other B vitamins are over 100%, but I never had a problem with them.

I also do great with the hydroxoB12, but don't tolerate high doses of folate.


Senior Member
I found a b-complex that i like from Biotics Research. 3 tablets contain 100% RDA so i start with half to one tablet a day.

Thiamin (B1) (as cocarboxylase chloride) 1.5 mg / 100%
Riboflavin (B2) (as riboflavin-5-phosphate) 1.7 mg / 100%
Niacin (as niacinamide) 20 mg / 100%
Vitamin B6 (as pyridoxal-5-phosphate) 2 mg / 100%
Folate (as calcium folinate) 400 mcg / 100%
Vitamin B12 (as methylcobalamin) 6 mcg / 100%
Biotin 300 mcg / 100%
Pantothenic Acid (as calcium pantothenate) 10 mg / 100%
Superoxide Dismutase (from vegetable culture) 60 mcg / *
Catalase (from vegetable culture) 60 mcg / *

Folinic acid gives me less side effects than methylfolate but i still can't go higher than 50mcg/day.
If i do so i get a tingling feeling in my feet and toes, it's a rather pleasant feeling but it disturbs my sleep.
What would cause that tingling feeling? Does anyone know?