Dietary Supplement Advanced B-12 Complex combines the two active, coenzymated forms of B-12 - methylcobalamin and adenosylcobalamin (dibencozide) - with hydroxocobalamin, a form that is transported throughout the body in the bloodstream. Vitamin B-12 is required for nerve and brain health, and for healthy red blood cells. It also works together with folate to maintain normal levels of homocysteine. Coenzyme supplementation reduces the body's need to synthesize the active forms of vitamin B-12 from the synthetic form, cyanocobalamin.