Dietary Supplement Vitamin B12 500μg Vitamin B12 is essential for the normal functioning of all cells in the body, especially those of the bone marrow, gastrointestinal tract and nervous system, and is also necessary for the formation of red blood cells. Useful in cases of anemia due to vitamin B12 deficiency. People with digestive disorders, the elderly, and vegetarians are commonly deficient in B12. Always use according to the manufacturers instructions. Its use does not replace classical medicine but complements it, which is why you should seek and follow a doctors advice and instructions.