Folic acid supplements are especially important for childbearing age and pregnant women. Vitamin B 12 is the largest and most complex of all the vitamins. The name vitamin B 12 is generic for a specific group of cobalt-containing corrinoids with biological activity in humans. It is the only known metabolite which contains cobalt, and soluble in water. This group of corrinoids is also known as cobalamins. The main cobalamins in humans and animals are hydroxo-cobalamin, adenosyl cobalamin and methyl cobalamin, the last two being the active coenzyme forms. Cyanocobalamin is a form of vitamin B 12 that is widely used clinically due to its availability and stability It is transformed into active factors in the body.