and how do we know if we are under of over? I've had issues with folininc acid so i don't use it, however i just received foloininc acid that is 67 mcg per serving (dropper) so i'm going to see if i can tolerate folininc in very low doses. ALSO is msm good for methylation? i'm taking hydroxy b12 (5000 mugs) i have burning tongue for over a year, and i've read it could be from low b12, my nutreval test shows a high need for b12. I'm taking 5000 mcg of hydroxy. If i have a high need , do you think i might need at least 10,000 mcg? also taking seeking health b minus and biotin... WHAT else to help methylation?