Thank you so much for your reply. I wondered abt lab error too. I do sporadically take my multi--which has extra b12. I don't eat a lot of fortified food (cereal, etc), but my new birth control has added folic acid.
What I haven't been able to understand is that many journals say folic acid will mask b12 deficiency--correct the anemia but not the neurological problems--what does that mean in serum labs? Will a serum level show high b12 that is not accessible to the cells? I do not think it's a kidney/liver problem--they did a full panel and I know my creatinine, etc were good. The only other off number (besides my TSH) was very low WBC--but I have always had that and no Dr seems to look further.
I will ask for another lab, I was thinking about the MMA too. Wondering if a urine might be helpful.