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RBC folate- is this just the l-5-MTHF inside the red blood cell? OR...

Messages
25
Hi all,

I was wondering if anyone knows when I get a blood test for RBC folate and serum folate (which are the 2 I get in Oz) what exactly is measured? I understand but could be worng, that RBC folate is inside the blood cells and Serum is outside the red blood cells.
But is the RBC folate actually JUST the l-5-MTHF or is it the 6S-5 MTHF(l type) + 6R-5-MTHF or does it include the folinic ones which would be (I think, correct me if I'm worng please) 5,10 Methylene THF and dihydrofolate or does it also include THF?
I've no idea what is being measured exactly.
My RBC folate is over 1900nmol/L , and without ANY supps and AVOIDING any folic acid added to foods or to supps for years it was always over 1250 (when they had an upper limit of 1250). My Mum's was always over 1250nmol/L too with no supps and no folic acid added to food. For both of us, these blood test results were over a decade(many tests each, quite a no of different labs) , every test.
With the same lab and test my husband measured 8nmol/L, so its not the lab or test, and his was low over a couple of tests as well.(and that was after folic acid was added to foods, when mine went over 1900nmol/L at same lab and time period).
So does anyone know if this is just 6s_5-MTHF (ie l-5-MTHF) or what it is ?

Thanks
 

alex3619

Senior Member
Messages
13,810
Location
Logan, Queensland, Australia
Hi tealady, I don't know what they actually test, I suggest contacting the pathology company and asking them. However, if they test for folate but not the other forms, this test is indicative of a functional folate deficiency. Perhaps Rich or Freddd can comment further. The reasoning is that if you cant convert folate, folate levels will rise. Bye, Alex
 
Messages
25
Hi all,

I was wondering if anyone knows when I get a blood test for RBC folate and serum folate (which are the 2 I get in Oz) what exactly is measured? I understand but could be worng, that RBC folate is inside the blood cells and Serum is outside the red blood cells.
But is the RBC folate actually JUST the l-5-MTHF or is it the 6S-5 MTHF(l type) + 6R-5-MTHF or does it include the folinic ones which would be (I think, correct me if I'm worng please) 5,10 Methylene THF and dihydrofolate or does it also include THF?
I've no idea what is being measured exactly.
My RBC folate is over 1900nmol/L , and without ANY supps and AVOIDING any folic acid added to foods or to supps for years it was always over 1250 (when they had an upper limit of 1250). My Mum's was always over 1250nmol/L too with no supps and no folic acid added to food. For both of us, these blood test results were over a decade(many tests each, quite a no of different labs) , every test.
With the same lab and test my husband measured 8nmol/L, so its not the lab or test, and his was low over a couple of tests as well.(and that was after folic acid was added to foods, when mine went over 1900nmol/L at same lab and time period).
So does anyone know if this is just 6s_5-MTHF (ie l-5-MTHF) or what it is ?

Thanks
m

Rich any idea of what the RBC folate blood test does actually measure, beside the folate inside the blood cells? i had thought it was ONLY 6S-5-MTHF but it may be the 6R type as well or folinic or folic acid or dihydrofate or every type...??
Wondering if high in RBC folate means high in 5-MTHF which would mean that part is working effectively but block in USING the 5-MTHF ??
 

Freddd

Senior Member
Messages
5,184
Location
Salt Lake City
m

Rich any idea of what the RBC folate blood test does actually measure, beside the folate inside the blood cells? i had thought it was ONLY 6S-5-MTHF but it may be the 6R type as well or folinic or folic acid or dihydrofate or every type...??
Wondering if high in RBC folate means high in 5-MTHF which would mean that part is working effectively but block in USING the 5-MTHF ??

Hi Tealady,

I have no knowledge at all about what it may mean. What I have seen is that most people who do trials either find that Metafolin works better for them, or not, regardless of what the many tests may say. Since many things depend on other cofactors, and Metafolin is no exception, they might be no difference taking Metafolin with hydroxycbl and all the difference in the world taking it with methylb12. The same may be true with as many as a dozen other factors.