The vitamin essential for energy in its most active form! Methylcobalamin is the most active form of vitamin B12, meaning it is absorbed and used easily by the body. Vitamin B12 is an important nutrient for energy, metabolism, red blood cell formation, and immune system health. Vitamin B12 Methylcobalamin helps prevent vitamin B12 deficiency, particularly in vegetarians and older adults, and anyone who has low stomach acid or malabsorption issues.