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How long to stop taking folate before test?

Messages
56
Does anyone know when I should stop taking methyl-folate before having serum folate levels checked? I know for B12 it is 10 days, but does that apply to folate as well?
Is red blood cell folate a better measure for folate levels? My lab won't be fasting, and I know serum folate is affected by recent nutrient intake.
Also, I really don't want to stop taking the B12 for 10 days, and I'm not even sure if my doctor will check it... what do other people do about that? Thanks!
 
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Learner1

Senior Member
Messages
6,305
Location
Pacific Northwest
RBC folate and methylmalonic acid are better tests for folate and B12. MCV is a clue, too, but won't tell you which you're low in.

Better yet, I do a Genova Diagnostics NutrEval every 9-12 months, as I've found even if I'm replete in folate and B12, I tend to run low in B1, B2, B6, magnesium, methionine, glycine, and molybdenum, which are all needed for methylation and the transsulfuration pathway.

Without these, I can't make glutathione properly, which led to my having mercury, arsenic, and lead toxicity, as well as stage 3 cancer, and tend to have other unpleasant stmptoms.

Folate and B12 are just the top of the iceberg, unfortunately.
 

pamojja

Senior Member
Messages
2,380
Location
Austria
Does anyone know when I should stop taking methyl-folate before having serum folate levels checked? I know for B12 it is 10 days, but does that apply to folate as well?
Is red blood cell folate a better measure for folate levels? My lab won't be fasting, and I know serum folate is affected by recent nutrient intake.
Also, I really don't want to stop taking the B12 for 10 days, and I'm not even sure if my doctor will check it... what do other people do about that? Thanks!

Never read there should be a 10 day abstinence of B12 before testing. Only the usual 12 fasting period for most nutrients in serum is recommended. Also can't think of any good reason for such an arbitrary abstinence, other then to know what your hypothetical serum levels would be, if you didn't supplemented (half-life in serum is around 24 hrs). But a preset, such as always 12 fasting hours before each test, should give more dependable results, comparable to everyday morning fasting levels.

After being vegetarian for 30 years without supplementation I tested the first time 179 pg/ml (187 - 883), with B12 supplementation the following years in average 1750 pg/ml. As in my example, I wouldn't waste the time or money for a test, for knowing levels which have no actuality, as in the example of 10 day abstinence. But want at least know where a certain intake takes my (12 hr fasting) serum levels.

All that not even considering that a serum B12 or B9 really don't tell much more. And as already mentioned, there are better tests, for example also Trancobalamin, or a Homocysteine (which if high could indicate deficiency mainly in B6, B9 and B12).

edit: clarification
 
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Messages
56
My homocysteine and methylmalonic acid levels were normal, in mid-range. My serum folate was low-ish. They were trying to figure out why my red blood cells are enlarged / fewer.
 

pamojja

Senior Member
Messages
2,380
Location
Austria
Normal for homocysteine with my lab given is 6.3-10 µmol/L, optimal would be considered by many below 8.
 
Messages
56
For my lab's reference ranges, homocysteine is 0 - 15 umol/L, and methylmalonic acid is 0 - 378 nmol/L. My homocysteine was around 7 and methylmalonic acid was around 200.

There wasn't a reference range given for serum folate, it just gave the deficiency marker as anything below 3.1 ng/mL, and mine was 6.1 ng/mL.

I guess I'm just having difficulty understanding why my CBC is abnormal when homocysteine and MMA are normal. It was suggested to me that perhaps "my normal" is to have enlarged red blood cells, but that is not the case, because when I was feeling healthier a couple of years ago, my CBC was normal and the cells were not close to being enlarged.
 
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