Like the name says, water-soluble vitamins dissolve in water. Toxic doses are unlikely as any excess is simply excreted in urine.
These vitamins cannot be stored in the body for a long time, so you must replenish them with a fresh intake every day. This water-soluble group is comprised of vitamin C and the B-complex vitamins, all very important vitamins to consume daily. The exceptions are the unofficial B vitamins choline and biotin which, although they are found in natural food sources, the body can actually manufacture itself.Riboflavin