Our optimal blend of methyl:adenosyl-cobalamin is unmatched in the market.  Methylated B12 has the highest bioavailability and efficacy. There is no upper tolerable limit on B12 as recommended by the FDA, so we want you to feel better and have more energy. B12 increases red blood cell formation and provides increased blood oxygenation which is how it has been proven to prevent some forms of anemia. Cobalamin is next to iron on the periodic table which may or may not have a correlation.