Vitamin B2 (Riboflavin)
Description
Riboflavin is found almost everywhere in foods and deficiency is rare. Because it has a yellow-orange colour, it has been used as food colorant as well as a for fortifying food.
Function
Riboflavin has two main active coenzyme forms: flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN). These coenzymes are part of the electron transport chain in oxidation-reduction reactions involved in the production of energy from glucose, amino acids, and fatty acids.
Deficiency
Isolated dietary deficiency is rare and is almost always accompanied by deficiencies of other B vitamins. Those may be caused by alcoholism or mal-absorption. Athletes and pregnant women also have a higher risk.
Signs of deficiency include angular stomatitis and cheilosis (inflammation and fissure of lips and corners of the mouth), seborrheic dermatitis (especially of the scrotum and nasolabial folds), anemia, glossitis (reddening and burning of the tongue), and neuropathy.
Sources
Riboflavin is ubiquitous. The best sources include milk and milk products. Other good sources are egg white, liver and green vegetables (e.g., asparagus, broccoli and spinach).
Toxicity
Taken orally, riboflavin is considered safe; no toxicity has been reported.
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Additional Sources of Information:
Scientific References
Books
Riboflavin. Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B6, Vitamin B12, Pantothenic Acid, Biotin, and Choline, Food and Nutrition Board, Institute of Medicine, Washington D.C.: National Academy Press; 1998:87-122.
PDR for Nutritional Supplements, Hendler SS, Rorvik DR, eds., Montvale: Medical Economics Company, Inc; 2001.
Riboflavin., McCormick DB., In: Modern Nutrition in Health and Disease. 9th ed., Shils M, Olson JA, Shike M, Ross AC, eds., Baltimore: Williams & Wilkins; 1999:391-399.
Riboflavin., Rivlin RS., In: Present Knowledge in Nutrition. 7th ed., Ziegler EE, Filer LJ, eds., Washington D.C.: ILSI Press; 1996:167-173.
Nutritional Biochemistry. 2nd ed., Brody T., San Diego: Academic Press; 1999.
Scientific Articles
A combination of riboflavin, magnesium, and feverfew for migraine prophylaxis: a randomized trial, Maizels M, Blumenfeld A, Burchette R., Headache. 2004;44(9):885-890.
[Abstract]
Antioxidative vitamins in prematurely and maturely born infants, Bohles H., International Journal for Vitamin and Nutrition Research, 1997;67(5):321-328.
Biochemical factors in the lens opacities. Case-control study. The Lens Opacities Case-Control Study Group, Leske MC, Wu SY, Hyman L, et al., Archives of Ophthalmology, 1995;113(9):1113-1119.
Current knowledge concerning optimum nutritional status of riboflavin, niacin and pyridoxine, Powers HJ., Proceedings of the Nutrition Society, 1999;58(2):435-440.
Determinants of plasma total homocysteine concentration in the Framingham Offspring cohort, Jacques PF, Bostom AG, Wilson PW, Rich S, Rosenberg IH, Selhub J., American Journal of Clinical Nutrition, 2001;73(3):613-621.
Diet and cataract: the Blue Mountains Eye Study, Cumming RG, Mitchell P, Smith W., Ophthalmology. 2000;107(3):450-456.
Diet and nuclear lens opacities, Mares-Perlman JA, Brady WE, Klein BE, et al., American Journal of Epidemiology, 1995;141(4):322-334.
[Abstract]
Effectiveness of high-dose riboflavin in migraine prophylaxis. A randomized controlled trial, Schoenen J, Jacquy J, Lenaerts M., Neurology. 1998;50(2):466-470.
[Abstract]
High-dose riboflavin treatment is efficacious in migraine prophylaxis: an open study in a tertiary care centre, Boehnke C, Reuter U, Flach U, Schuh-Hofer S, Einhaupl KM, Arnold G., European Journal of Neurology. 2004;11(7):475-477.
[Abstract]
Interrelationships between riboflavin and vitamin B6 among elderly people (Dutch Nutrition Surveillance System), Lowik MR, van den Berg H, Kistemaker C, Brants HA, Brussaard JH., International Journal for Vitamin and Nutrition Research, 1994;64(3):198-203.
[Abstract]
Long-term nutrient intake and 5-year change in nuclear lens opacities, Jacques PF, Taylor A, Moeller S, et al., Archives of Ophthalmology. 2005;123(4):517-526.
[Abstract]
Nutrient intake and cataract extraction in women: a prospective study, Hankinson SE, Stampfer MJ, Seddon JM, et al., BMJ. 1992;305(6849):335-339.
[Abstract]
Nutritional needs of seniors, Blumberg J., Journal of The American College of Nutrition, 1997;16(6):517-523.
[Abstract]
Pharmacokinetics of orally and intravenously administered riboflavin in healthy humans, Zempleni J, Galloway JR, McCormick DB., American Journal of Clinical Nutrition, 1996;63(1):54-66.
Prophylactic treatment of migraine with beta-blockers and riboflavin: differential effects on the intensity dependence of auditory evoked cortical potentials, Sandor PS, Afra J, Ambrosini A, Schoenen J., Headache. 2000;40(1):30-35.
[Abstract]
Riboflavin and vitamin B-6 intakes and status and biochemical response to riboflavin supplementation in free-living elderly people, Madigan SM, Tracey F, McNulty H, et al., American Journal of Clinical Nutrition, 1998;68(2):389-395.
Riboflavin deficiency and preeclampsia, Wacker J, Fruhauf J, Schulz M, Chiwora FM, Volz J, Becker K., Obstetrics and Gynecology. 2000;96(1):38-44.
[Abstract]
Riboflavin supplementation and preeclampsia, Neugebauer J, Zanre Y, Wacker J., International Journal of Gynecology & Obstetrics, 2006;93(2):136-137.
[Abstract]
Riboflavin-iron interactions with particular emphasis on the gastrointestinal tract, Powers HJ., Proceedings of the Nutrition Society, 1995;54(2):509-517.
Role of physiological antioxidants in chromium(VI)-induced cellular injury, Sugiyama M., Free Radical Biology and Medicine, 1992;12(5):397-407.
[Abstract]
The effect of exercise on the riboflavin status of adult men, Soares MJ, Satyanarayana K, Bamji MS, Jacob CM, Ramana YV, Rao SS., British journal of Nutrition, 1993;69(2):541-551.
The influence of vitamin B2 intake on the activation coefficient of erythrocyte glutation reductase in the elderly, Lopez-Sobaler AM, Ortega RM, Quintas ME, et al., Journal of Nutrition, Health & Aging, 2002;6(1):60-62.
[Abstract]
The relationship between riboflavin and plasma total homocysteine in the Framingham Offspring cohort is influenced by folate status and the C677T transition in the methylenetetrahydrofolate reductase gene, Jacques PF, Kalmbach R, Bagley PJ, et al., Journal of Nutrition, 2002;132(2):283-288.
Two interconnected B vitamins: riboflavin and pyridoxine, McCormick DB., Physiological Reviews. 1989;69(4):1170-1198.
[Abstract]
Vitamin requirements of elderly people: an update, Russell RM, Suter PM., American Journal of Clinical Nutrition, 1993;58(1):4-14.
