Methylcobalamin Vitamin B12 supplements provide essential nutrients for the support of the heart and cardiovascular system. Methylcobalamin is the active form of Vitamin B12 and is primarily used in treating Vitamin B12 deficiency related diseases. Vitamin B12 plays an important role in red blood cells development, prevention and treatment of pernicious anemia, methylation reactions, and immune system regulation. Methylcobalamin has some unique metabolic and therapeutic applications not shared by the other forms of Vitamin B12. Methylcobalamin is the active form of Vitamin B12 that helps in lowering blood levels of homocysteine.