Vitamin B12
Vitamin B12, or cobalamin, is a water‑soluble vitamin essential for neurologic function, red blood cell formation, and DNA synthesis. It is naturally present in animal-derived foods and certain fortified products, absorbed in the ileum via an intrinsic factor–mediated process, and functions as a cofactor for methionine synthase and methylmalonyl‑CoA mutase. Deficiency can cause megaloblastic anemia and neuropathy and is most common in older adults, people with malabsorption, and individuals following strict vegan diets.
