Thanks. I will look into those links for sure.

I found something yesterday after reading an old thread about types of B12 on here and doing something sniffing around the internet. I wonder if you know any more about it?

I looked up homocysteine and found that the majority of the info is about people with high levels and the implication of heart disease but it made me start wondering about a possible LOW level and if that's problem or not. I found 1 article about a study of low levels and the effect. I turns out that a low level can affect many many systems negatively although it didn't get into specifics (unfortunately). It seems to not be on the average Dr's radar. They use B12 and folic acid to lower homocysteine levels in those with heart disease and in athlete's to increase endurance. It seems that that COULD explain why I felt worse on the B12 and the folic acid and better directly after exercise. The exercise would bring a low level back into range and the supplements would lower it further. Obviously, I'll have to get the level checked anyway to see if it could be a factor or not, but I thought it was interesting and wondered if anybody know any more?