Do you or anyone have any research into which blood test is best? I can source either the EGRAC test or HPLC.
Valid testing for vitamin B2 levels - riboflavin
There are 1123 posts on this thread ...but does B2 have any relevance for me? That is, any valid way to measure it in me? I tried to dig hard to find scientific evidence and here it is: The only test that is largely valid
and is practically available is the EGRAC = erythrocyte glutathione reductase activation coefficient.
This is the most extensive and new (August 2017) scientific text I found:
http://onlinelibrary.wiley.com/doi/10.2903/j.efsa.2017.4919/full
Here the essentials:
The Panel considers that the inflection point in the urinary riboflavin excretion curve in relation to riboflavin intake reflects body saturation and can be used as a biomarker of adequate riboflavin status. The Panel also considers that erythrocyte glutathione reductase activation coefficient is a useful biomarker, but has limitations.
- This means: There is a valid urinary test. It is, however, not offered by anyone. The EGRAC limitations ane nothing to worry about, just that physical activity can falsify it, and: "EGRAC cannot be used in people with G6PD deficiency".
Section 2.4.3 analyses in all detail various ways of testing B2 in blood and it is not considered valid, but I did not find any useful statement on how wrong it is.
I am glad I found one single lab here (Unilabs) offering the EGRAC. (All others test only B2 in blood.) They didn't make it easy for me and named their EGRAC in a fancy way: FADxcoeff.... This fancy name costed quite some delay in searching but I am more happy than annoyed because THEY DO IT!
I already had a similar story with thiamine testing:
A doctor led me astray by non-valid testing of thiamine. Her simple blood test came back good. I had to find out that the
valid test showed a huge deficiency. I earned a substantial improvement after a rather
troublesome course of supplementation, and after learning
100 details about B1, which I never would have done if not knowing that I am badly deficient. ➞ Valid testing pays!
PS: If anyone interested, attached to
this post there is a document containing a list of valid tests for several vitamins.