Vitamin B-12 is a naturally occurring B Complex vitamin that promotes the health of the circulatory and nervous systems.* Each nutrient in the B Vitamin Complex performs a unique role in maintaining proper metabolic functioning and is essential for well-being.* Vitamin B-12 supports energy metabolism by working with enzymes involved in the breakdown of nutrients, such as amino acids.* It is also vital for the normal formation of blood cells, and is involved in DNA synthesis and renewal.