Water soluble vitamins are a heterogeneous group of compounds that differ chemically but share the common characteristic of being soluble in water. They are easily absorbed and not stored in the body except for vitamin B12. The document focuses on various water soluble vitamins including vitamin C, the B vitamins (thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folic acid, cyanocobalamin), their roles, dietary sources, requirements and deficiency manifestations.