Nutrifactor’s Vitamin B-12 is a dietary supplement containing a water-soluble B-vitamin Cyanocobalamin (Vitamin B12), which is vital for fat and protein metabolism as well as energy production. It also plays an important role in the formation of healthy red blood cells. Vitamin B-12 is a key factor in DNA synthesis during cell division and therefore is especially important for rapidly multiplying cells, such as blood cells. It is also vital for the normal functioning of the nervous system and heart.