B Vitamin Overview

The B vitamins, including thiamin (B1), riboflavin (B2), niacin (B3), pyridoxine (B6), folacin (folic acid), cyanocobalamin (B12), biotin, and pantothenic acid (B5), are water-soluble vitamins that are stored and carried by water in the body. B vitamins must be taken daily because water is constantly being lost in urine, sweat, and other body fluids. The B vitamins should always be taken together, since they work in the body as a team.

It is commonly found that ingestion of B vitamins will cause the urine to become a bright yellow color as it is eliminated from the body. This isn't harmful and doesn't mean that the vitamins aren't being well-absorbed. In particular, ingestion of riboflavin (B2) gives the urine a characteristic bright yellow fluorescent glow, indicating that the supplement is being well-absorbed (1,2). Riboflavin is a yellow-green pigment belonging to a group of fluorescent pigments called flavins. Riboflavin food sources include organ meats (liver. kidney, heart), milk, almonds, whole grains, soy beans and green leafy vegetables.