Vitamin B 12 is essental for efficient working of every cell in the human body, especially those cells that undergo rapid turnover, such as red blood cells, the lining of the gut, and blood vessels. It is involved with the synthesis of DNA, the body's genetic material. It also is essential for proper development and functioning of the nervous system. Research has found that increased doses of B 12 can reduce Alzheimer's disease if taken under the tongue or via injection.
Craig