by Jennifer Brett, N.D.

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Brett, N.D., Jennifer.  "How Vitamin B2 Works."  22 December 2006.  HowStuffWorks.com. <http://recipes.howstuffworks.com/vitamin-b-2.htm>  04 July 2008.
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What Is Vitamin B2?

Most nutritionists in the 1920s believed that there were only two unidentified essential nutrients -- a fat-soluble A and a water-soluble B. Soon, however, they found there was a second water-soluble B compound waiting to be identified.

Milk is a good source of vitamin B2, or riboflavin.
�2007 Publications International, Ltd.
Milk is a good source of vitamin B2,
or riboflavin.

Nutritionists gradually isolated growth-producing substances from liver, eggs, milk, and grass. In 1933, L. E. Booher obtained a yellow growth-promoting substance from milk whey, observing that the darker the yellow color, the greater its potency. Booher's observation led nutritionists to discover that all the yellow growth-producing substances in foods were one and the same -- riboflavin.

While nutritionists zeroed in on the yellow substance in food, biochemists studied a yellow enzyme found to be essential for the body's energy needs. Biochemists were eventually able to separate the enzyme into two parts: a colorless protein and a yellow organic compound that turned out to be the riboflavin itself. This was the first clue scientists had that there is more than one B vitamin.

Functions of Vitamin B2

Riboflavin acts as a coenzyme -- the nonprotein, active portion of an enzyme -- helping to metabolize carbohydrates, fats, and proteins in order to provide the body with energy. Riboflavin doesn't act alone, however; it works in concert with its B-complex relatives, particularly B6 (pyridoxine). Riboflavin also has a role in the metabolism of other vitamins.

Riboflavin has a connection to glutathione, one of the enzymes that rids the body of free radicals. It helps in the regeneration of this beneficial compound.


Riboflavin has many health benefits -- it is thought to decrease migraines, help prevent cataracts, and even alleviate sickle-cell disease. Keep reading to learn more about riboflavin's therapeutic value.

Riboflavin is just one of many vital nutrients your body needs for overall health. Visit the links below to learn more about these essential vitamins.
  • In How Biotin Works, learn how biotin acts as a coenzyme in several metabolic reactions, such as the metabolism of fats and carbohydrates.
  • Read How Folate Works to learn about folacin, folic acid, and folate and how a folate deficiency can cause megaloblastic anemia.
  • Vitamin B12, also called cyanocobalamin or cobalamin, is essential because it assists folate in making DNA and RNA. Read more in How Vitamin B12 Works.
  • Vitamin C, or ascorbic acid, is good for more than just easing the common cold. Learn more in How Vitamin C Works.
  • Vitamin D is necessary to hold of rickets, but if you get enough sunshine, your body can make its own vitamin D supply. Learn more in How Vitamin D Works.
  • To learn about the many vitamins in our diet, how much you should be eating, and where to find them, go to our general Vitamins page.
  • To find the best prices on vitamin B2 supplements, click here.
This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.

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