If you've been tested for MTHFR and it's come up that you're heterozygous or homozygous for one or both of the SNPs, chances are that someone has told you you need to take methylated B12 and folate, and someone else has told you NOT to, because you could end up overmethylated. What's a poor MTHFR to do?
Well, I just found a real nugget at mthfr.net - a quick & easy test to see if you're overmethylated (and need to take a non-methylated version of B12 like hydroxycobalamin) or whether you're undermethylated, and desperately need methylcobalamin, the methylated form of B12.
Ready? Here goes:
Methods to Understand if You’re Hypomethylated or Hypermethylated
"Take some Niacin in the form of nicotinic acid. Chew 1/10th a tablet of Niacin and then swallow. Niacin utilizes s-adenosylmethionine (SAM) when breaking down. If you flush strongly on 50 mg, you are likely hypomethylated (lack of SAM). If you do not flush much, you are likely a ‘normal methylator’ (balanced SAM). If you do not flush at all, you may be hypermethylated (excessive SAM).
Side Effects from Methylfolate: If you are taking methylfolate and experiencing these side effects, then you are likely hypermethylated."
Well, except for those who are hypomethylated and then get hypermethylated due methyl trapping from problem SNPs further on down the line. But if that happens, just nibble on some more niacin, and schedule with your MTHFR doctor.