The B12 in many supplements is cyano form. This type requires 4 conversion steps to get to methyl form which is the type the body uses.
If you are not converting, it is just hanging around in the blood doing nothing. So I think you should try ACTIVATED B12 (methylcobalamin) for 3 months and then get retested.
People who cannot convert folate and B12 to their active forms have a genetic problem called a MTHFR polymorphism. It is estimated that 1 in 10 people have this. There is a DNA test for it that is even over the counter now! (no doctor needed)
B12 has to be actively transported in the cerebrospinal fluid as well. Serum levels, may or may or correspond to what is in the CSF. Some neuro conditions have been found to have low CSF B12 levels...Multiple sclerosis and Fibromyalgia are two that have papers written about that.
So the bottom line for you would be to use the active forms of both folate and B12. Both are OTC and this thread gives examples of products to buy:
http://neurotalk.psychcentral.com/thread114302.html
Metanx is the RX version, but all 3 activated vitamins are available OTC too. (methylfolate OTC is 800mcg maximum dose).
This is my B12 informational thread:
http://neurotalk.psychcentral.com/thread85103.html
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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