Vitamin B2: Riboflavin
Vitamin B2, also called riboflavin, is a water-soluble vitamin. Water-soluble vitamins are stored in the body in very limited amounts and are excreted through the urine. Therefore, it is a good idea to have them in your daily diet. Vitamin B2 is a component of two enzymes: flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These coenzymes are important in energy production.
Functions
Riboflavin’s functions include:
- Assisting in energy production
- Helping to synthesize normal fatty acids and amino acids
- Helping the nervous system to function efficiently
- Aiding in cellular growth
- Assisting in the metabolism of certain other vitamins
Recommended Intake:
| Age Group (in years) | Recommended Dietary Allowance | |
|---|---|---|
| Females | Males | |
| 1-3 | 0.5 milligrams (mg) | 0.5 mg |
| 4-8 | 0.6 mg | 0.6 mg |
| 9-13 | 0.9 mg | 0.9 mg |
| 14-18 | 1.0 mg | 1.3 mg |
| 19-70 | 1.1 mg | 1.3 mg |
| Pregnancy | 1.4 mg | n/a |
| Lactation | 1.6 mg | n/a |
Riboflavin Deficiency
Riboflavin deficiency occurs as part of multiple nutrient deficiency states. Since riboflavin occurs in a wide variety of foods, deficiency symptoms are rare. Symptoms have been reported when daily riboflavin intake falls below 0.6 milligrams (mg). Symptoms of riboflavin deficiency include:
- Cracks in the corner of the mouth (cheilosis)
- Inflammation of the mucous membranes of the mouth
- Sore or inflamed tongue (glossitis)
- Reddening of the eyes
- Eyes that tire easily, burn, itch, or are sensitive to light
- Dimming of vision
- Unusual skin inflammation (dermatitis) characterized by simultaneous dryness and greasy scaling
- Depression, hysteria, or other psychiatric problems caused by nerve tissue damage or decreased neurotransmitter production
- Malformations and retarded growth in infants and children
Riboflavin Toxicity
Riboflavin is relatively nontoxic. Although no adverse effects have been associated with high intakes of riboflavin from food or supplements, the potential may exist. Therefore, caution may be warranted with excessive amounts of riboflavin.
Major Food Sources
| Food | Serving size | Riboflavin content |
|---|---|---|
| Beef liver, braised | 3 ounces | 3.5 milligrams (mg) |
| Yogurt, skim with dry milk solids | 1 cup | 1.6 mg |
| Broccoli, cooked | 1 2/3 cups | 0.5 mg |
| Spinach, cooked | 1 1/3 cups | 0.5 mg |
| Milk, skim | 1 cup | 0.4 mg |
| Enriched corn tortilla | 1 tortilla | 0.2 mg |
| Egg | 1 large | 0.1 mg |
| Whole grain bread | 1 slice | 0.1 mg |
Health Implications
Populations at Risk for Riboflavin Deficiency
The following populations may be at risk for riboflavin deficiency and may require a supplement:
- People who consume excessive amounts of alcohol
- People with other nutrient deficiencies
- Infants with jaundice who are treated with specialized light therapy
- People with anorexia nervosa
- Individuals who avoid dairy products
- Malabsorption (celiac sprue, malignancy, etc)
- Long term use of barbiturates (eg, phenobarbital)
Prevention of Cataracts
Several studies have suggested that riboflavin may play a role in the prevention of cataracts; however, further studies are needed to confirm this relationship.
Treatment of Migraine Headaches
Preliminary findings from a randomized placebo-controlled trial suggested that riboflavin supplementation might be a useful in addition to beta-blockers to help prevent migraine headaches.
Tips for Increasing Your Riboflavin Intake
To help increase your intake of riboflavin:
- Include dairy products in your daily diet, such as milk, yogurt, and cheese.
-
Eat foods rich in riboflavin such as:
- Liver
- Mushrooms
- Leafy green vegetables
- Eggs
- Enriched bread, rolls, and crackers
- Meats
Riboflavin is rapidly destroyed with exposure to sunlight. Therefore, foods containing riboflavin are best stored in a pantry, in bins, and, when perishable, in the refrigerator.
RESOURCES:
American Dietetic Association
http://www.eatright.org/Public/
Food and Nutrition Information Center
US Department of Agriculture
http://www.nal.usda.gov/fnic/
References
The Nutrition Desk Reference. Keats Publishing; 1995.
Facts about dietary supplements. National Institutes of Health website. Available at: http://www.nih.gov .
Food and Nutrition Information Center. US Department of Agriculture website. Available at: http://fnic.nal.usda.gov/nal_display/index.php?tax_level=1&info_center=4 .
The Linus Pauling Institute website. Available at: http://lpi.oregonstate.edu/ .
DiDonato S, Geller, C, Peluchetti D, et al. Normalization of short-chain acylcoenzyme A dehydrogenase after riboflavin treatment in a girl with multiple acylcoenzyme A dehydrogenase-deficient myopathy. Ann Neurol. 1989;25:479-484.
Wilson, JA. Vitamin deficiency and excess. In: Harrison's Principles of Internal Medicine. 14th ed. Fauci AS, Braunwald E, Isselbacher K, et al. eds. New York, NY: McGraw-Hill; 1998:481.
Last reviewed February 2007 by Marcin Chwistek, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © 2011 EBSCO Publishing All rights reserved.