I have been experimenting with @Freddd 's methylation protocol, or some approximation of it, for many months now. I am having a hard time striking the right balance. At first I had excellent results with just hydroxyB12, but then it became clear I was low on other b vitamins. I then had positive start-up reactions with B1 and methylfolate (after I realized his concept of paradoxical folate deficiency certainly applies to me). I ended up titrating methylfolate to an extremely high dose of around 30mg, which turned out to be a bad idea, it was way more than I needed---I ended up with scary muscle weakness. But in my experimentation, I've been having some blurry vision and floaters. My vision gets worse for a few days, then I seem to find the right combination of b vitamins and it gets better, but often only temporarily. Anyone else have this issue? Any recommendations for the best tests for b vitamin levels to see if I can find a better way to figure out what my nutrient needs are?