Better known as riboflavin, it acts as a co-enzyme in respiratory enzyme systems. Vitamin B 2 is a prime constituent of flavor proteins, essential in the maintenance of healthy skin, oxidation reduction (redox) systems and eye tissue. It is a principal agent in blood revitalization; and an absence of it can bring about anemia.
ref: Silent Healer (pg. 54) by Bill coats, P.PH., with Robert Ahola