mrsD, Thank you. I have been B12 deficient 6 years that I know of, maybe more. I was sure that I had fixed it by taking hundreds of B12 vitamins, trying to get my number up to 1000 which is where it should be with the type of neuropathy I have. I switched to methyl b12 when I saw the post where you explained that many of us can't convert the non -methyl kind. I pulled medical records and there was a methylenation report showing that there was a problem which needed further investigation. All I was ever told, was to take a multi-vitamin. Since I could never tolerate muti's I let it go, not thinking it was a big deal. After looking into the site Marlene recommended, it connected many dots and clearly there's a problem which finally can be addressed and reversed. The MTHFR genetic page probably sends many away, as it did me, thinking they don't have it. I am going to get L-methylfolate today and start slowly as recommended. The knowledge that you both have generously shared is very much appreciated.