I've been taking massive doses of vit C past 8 months - I think my digestion is ok (I have included daily digestive enzymes as part of one protocol recently) I don't know if I have malabsorption issues or not. I did daily B12 shots for a couple of years - I tried to get same effect orally or sublingually with no luck.
I think my problem is hypercoagulation, it's the body's defense against "something" (viral, bacterial, toxin, something) Brownstein explains the body releases "fibrin" blockages so the "something" doesn't have free access to the whole body through the blood supply. Years of build up of the fibrin stop the "something" from free access but also slow the blood supply of oxygen & nutrients to the cells.
I am currently doing multiple protocols including a mercury detox. I just started a protocol for the hypercoagulation to clear the fibrin, open up the blood flow & hopefully clear the problem. I'm hoping if nothing else to restore some functionality.