I'm new to the site although I've lurked for a while, but I thought I'd pop in and mention something quite interesting that I discovered recently.
Trying to cut a long story a lot shorter, I developed ataxia and no one could pin down the cause. I was also quite a while ago diagnosed with a B12 deficiency. The B12 seemed to improve things a great deal but doctors said that the problem had been reversed and refused to give me a shot more than once every couple of months.
I was certain the B12 was something to do with things though, but didn't get too far in finding anything out - then, over the Christmas period I was talking to a woman (via a forum for people who do book reviews) who had just read a book called B12 Deficiency and Chronic Illness by a guy called Mike Newman. She said that B12 deficiency was at the bottom of a lot of problems related to all kinds of stuff (she has CFS) and that ataxia was one of them and that modern docs had been getting it wrong and B12 deificency was actually more a condition of the nervous system than the blood.
I was seriously dubioius, but, like many of you, a bit desperate as my condition is, on the whole, deteriorating. When I bought the book I found out she was right! Apparently this condition always used to be known for the problems it causes to the nervous system but over the years the whole thing has got sort of twisted out of shape because of the links with the blood. B12 deficiency has also been strongly linked to motor neurone disease and there is an organisation in the U.S. (I think) which, based on real research, suggests that people suffering with it take as much as 25mg by injection PER DAY.
Anyway, because it's the holidays I haven't been able to try it yet or talk to my doctors about it. But I really do think this guy is on to something.
Best wishes for the holiday season (if I'm not too late)