AOR Methyl B12 - 5 mg - The coenzyme form of vitamin B12 which supports the healthy structure and function of the nerves and brain. Several studies have found that people can have neurological signs and symptoms of a specific Methylcobalamin deficiency, even when serum B12, and blood tests which measure adenosylcobalamin activity, are perfectly normal. This is in large part because, while the body can store adenosylcobalamin (the other coenzyme form of vitamin B12) in the liver and mitochondria, Methylcobalamin is located in fluids like the cerebrospinal fluid and plasma, and is urinated out rather than stored.