Re B12: It can be difficult to get it into the cells. I did injections for a few years with no apparent benefit (didn't feel any different). Then I switched to sublingual and still felt no different. And then tried liquid sublingual methylB12, and took two 5000 mcg doses a day, and
finally felt a boost in energy. For me, the liquid works the best. I did the shots self-injecting 3 times and it just wasn't enough.
Re methylfolate - yes, you very well could need more. The 6.4 mg that
@ljimbo423 takes is quite a high dose - you should work up gradually and see how you do. I had a noticeable boost in energy with 1600 mcg. But we're all different.
Re B6 - 3 mg. of P5P is not very much at all. Nutreval testing showed a severe B6 deficiency for me as well and I ended up needing 150 mg. P5P a day (divided into 2 doses).
Re B1 - it can make a big difference in how you feel. When I started taking thiamine, I had an almost immediate boost in energy - it was amazing. I'm now taking 100 mg thiamine and 150mg benfotiamine a day, but am going to switch to just benfotiamine when I finish my regular thiamine.
A word of caution: with both the methylfolate and the B1, I experienced very pronounced symptoms of refeeding syndrome. With the folate (and it often happens when people take B12 as well), after the initial energy boost, within 2 or 3 days I was hit with severe fatigue - my potassium levels had dropped quite a bit very quickly. Fortunately I had read about this possibility on Freddd's posts about methylation and started taking potassium in divided doses, titrating up to 1000 mg a day over a couple of days, and the severe fatigue went away. I subsequently learned I had to keep taking potassium (it's been 8 years now) but it works.
With the B1, I also developed severe fatigue after an initial boost, but it was different than the fatigue from low potassium. Because I'd done reading on refeeding syndrome, I theorized it might be low phosphorous from refeeding syndrome and drank several glasses of kefir, and that fatigue finally went away too and I was able to keep taking the thiamine. Otherwise I would have had to stop it.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2440847/
Your muscle spasms and twitches could be due to low magnesium, as Caledonia suggested, or low potassium. You could try drinking several glasses of low-sodium V8 or vegetable juice which is high in potassium and see if it helps. You would know relatively quickly I think, likely within a few hours. A few bananas probably would not be enough. I like the low-sodium V8 because it's low in sugar.
People with ME/CFS can have low intracellular potassium despite normal levels in blood work. See
http://forums.phoenixrising.me/inde...ded-in-methylation-treatmt.18670/#post-291422