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How Vitamin B2 Works


Foods That Contain Vitamin B2
Milk is the single best source of vitamin B2 in the American diet. A glass of milk provides one-quarter of the RDA of riboflavin for men and one third of the RDA for women. Other dairy products such as cheese, yogurt, and ice cream are also good sources of the vitamin. Meats, especially liver and kidney, and some green leafy vegetables are other rich sources. Enriched breads and cereals have riboflavin added to them.

Dairy products, such as milk, cheese, and yogurt, are excellent sources of riboflavin.
©2007 Publications International, Ltd.
Dairy products, such as milk, cheese, and yogurt, are excellent sources
of riboflavin.

Heat and oxygen do not easily destroy riboflavin, but light does. Milk can lose one-half or more of its riboflavin content when exposed to light for four to six hours. To prevent this from occurring, it's important not to store milk in clear glass or translucent plastic containers. It's better to buy and store milk in cardboard containers or colored plastic jugs.

Dietary Requirements of Vitamin B2

The RDA for riboflavin is 0.5 mg for every 1,000 calories. This works out to be 1.3 mg each day for the average adult man and 1.1 mg for the average adult woman. A pregnant woman needs an additional 0.3 mg. During a baby's first six months, a nursing mother needs an additional 0.5 mg daily; during the second six months, she needs only 0.4 mg more. Recommended levels decrease slightly to 1.4 mg for men and 1.2 mg for women over age 50 as energy needs decrease.

You can use this chart to find foods that are a good source of riboflavin.

Food Quantity
Riboflavin (mg)
Milk shake, thick 1 cup 0.5
Cottage cheese, low-fat 1 cup 0.41
Milk, whole 1 cup 0.39
Buttermilk, from whole milk 1 cup 0.38
Buttermilk, from skim milk 1 cup 0.37
Yogurt, low-fat frozen 1 cup 0.37
Pancakes 3 medium 0.36
Sweet potatoes 1 cup 0.33
Pretzels 1 cup 0.25
English muffin 1 medium 0.24

Hypersensitivity to light can be a sign of a riboflavin deficiency, which causes the skin to become greasy, scaly, and dry. Keep reading to learn more about the effects of a riboflavin deficiency.

Riboflavin is just one of the essential vitamins that should be a part of your diet. Follow the links below to learn more about the nutrients your body needs.
  • Vitamin B5, or pantothenic acid, can be found in all living cells and in all foods. Learn about its importance to your diet in How Vitamin B5 Works.
  • Vitamin B6 is actually three substances, pyridoxine, pyridoxamine, and pyridoxal, that work to metabolize protein and amino acids. Read more in How Vitamin B6 Works.
  • 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.
  • 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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