I know that B-12 is important (I had extremely violent reactions to B-12 when I was still poisoned), but some people are just so seriously ill that they don't react or get any benefit from ordinary supplements like B-12, B-6, zinc, vit C, folic acid etc. The reason may be in the transsulfuration pathway being seriously broken, and as a result glutathione seriously depleted. In this case, anything that helps raising glutathione will be helpful, but ordinary supplements just doesn't seem to be efficient enough. Glutathione can't be supplemented directly, the body can't use it.