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Ingredient Type: Vitamin

Also Known As: Vitamin G, Riboflavin, Flavin

Vitamin B-2 (riboflavin) is one of eight B vitamins and an essential nutrient for all animals, obtained only through the diet.  It is found in organ meats, cheese, eggs, mushrooms, and nutritional yeast.  Riboflavin functions as a coenzyme, meaning that it is required for enzymes (proteins) to perform normal physiological actions.  Deficiency results in stomatitis, including painful red tongue with sore throat, chapped and fissured lips, and inflammation of the corners of the mouth.

As a chemical compound, riboflavin is a yellow-orange solid substance with poor solubility in water compared to other B vitamins.  Visually, it imparts color to vitamin supplements (and bright yellow color to the urine of persons taking a lot of it).

Vitamin B-2 is used in health supplements today to support glandular function and vision.  It also plays a key role in the metabolism of fats, proteins, carbohydrates, and other B vitamins.


In the meantime see the MedlinePlus entry for riboflavin, the entry for vitamin B2, the Michigan Medicine Health Library entry for vitamin B2, or the RXList entry for riboflavin for more information.