What happened: I gradually worked up to 400mcg methylfolate w/ mB12. With each step up I got big improvements in energy, mood, and my need for thyroid and ribose dropped off. But at the 400mcg mark I developed severe insomnia - COULD. NOT. SLEEP. Similar effect to taking 400mg SAMe. I dropped back down to 267mcg methylfolate, but still had powerful insomnia. I went off methylfolate for 4 days. Took Nicotionic acid as needed. The insomnia gradually decreased each night I was off. I could sleep again. On Monday I started over again with just 67mcg methylfolate, thinking that wold be more gentle. The insomnia came right back. But my energy / PEM threshold has risen. What I surmise from my reactions: It appears that my methylation cycle was previously disrupted or broken. It appears that taking methylfolate with B12 restarted my methylation cycle successfully, keeping it going even after I stopped methylation supplements. It appears I am very sensitive to methylfolate. (I'm more like @Avalon or @caledonia, less like @Freddd ) It appears I am mostly tolerant to mB12 - it feels good, doesn't seem to bother me. I don't know my SNPs: I was rejected by 23andMe. I may need some sort of very low dose methylation support - preferably some kind of support that lets my body control its own rate of methylation. Hydroxycobalmin? Folinic acid? ??? Since Monday I have been off almost all supplements (except fish oil, NT Factor energy lipids, Vitamin C, thyroid and magnesium). I have depended on daily supplements for years. To my surprise, I seem to have PLENTY of energy... I don't feel like a "CFS sufferer"... I am active all day and wait for PEM to come and it just doesn't really hit me like it did pre-Methylation experiment. But I still feel a little bit "off balance".. sometimes "undermethylated" and sometimes "overmethylated" and have some insomnia. I am not cured, but definitely inspired. I am considering going on Yasko's All-in-One multivitamin which boasts "VERY LOW dose methylation support" - 25mcg folate per pill. How long should I wait before starting up methylfolate again? Do some people require short-term methylation support only, and then they are back up and running for a long time? Can you see any kind of pattern or offer insights / cofactors that may be important? thank you.