Mission, Asheville, NC - Vitamin B2 (Riboflavin). Overview: Vitamin B2, ...

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Vitamin B2 (Riboflavin)

Overview:

Vitamin B2, also called riboflavin, is one of 8 B vitamins. All B vitamins help the body to convert food (carbohydrates) into fuel (glucose), which is "burned" to produce energy. These B vitamins, often referred to as B complex vitamins, also help the body metabolize fats and protein. B complex vitamins are necessary for healthy skin, hair, eyes, and liver. They also help the nervous system function properly.

All the B vitamins are water-soluble, meaning that the body does not store them.

In addition to producing energy for the body, riboflavin also works as an antioxidant by scavenging damaging particles in the body known as free radicals. Free radicals occur naturally in the body but can damage cells and DNA, and may contribute to the aging process as well as the development of a number of health conditions such as heart disease and cancer. Antioxidants such as riboflavin can neutralize free radicals and may reduce or help prevent some of the damage they cause.

Riboflavin is also needed to help the body convert vitamin B6 and folate into active forms.

Most healthy people who eat a well-balanced diet get enough riboflavin. However, elderly people and alcoholics may be at risk for riboflavin deficiency because of poor diet. Symptoms of riboflavin deficiency include fatigue; slowed growth; digestive problems; cracks and sores around the corners of the mouth; swollen magenta tongue; eye fatigue; swelling and soreness of the throat; and sensitivity to light. Riboflavin is an important nutrient in the prevention of headache and some visual disturbances, particularly cataracts.

Anemia

Children with sickle-cell anemia (a blood disorder characterized by abnormally shaped red blood cells) tend to have lower levels of certain antioxidants, including riboflavin. The same is also true of people with iron deficiency anemia, and studies suggest that taking riboflavin supplements may improve the response to iron therapy.

Cataracts

Vitamin B2, along with other nutrients, is important for normal vision, and there is some preliminary evidence that riboflavin might help prevent cataracts (damage to the lens of the eye which can lead to cloudy vision). In one double-blind, placebo-controlled study, people who took a niacin-riboflavin supplement had significantly less cataracts. However, researchers don't know whether that was due to riboflavin, niacin, or the combination of the two. And levels above 10 mg per day of riboflavin can actually promote damage to the eye from the sun. More research is needed to see if riboflavin has any real benefit in preventing cataracts.

Migraine Headache

Several studies indicate that people who get migraines may decrease the frequency and duration of the headache by taking riboflavin. One double-blind, placebo-controlled study showed that taking 400 mg of riboflavin a day cut the number of migraine attacks in half. The study did not compare riboflavin to conventional medications used to prevent migraines, however, so more research is needed.

Dietary Sources:

The best sources of riboflavin include brewer's yeast, almonds, organ meats, whole grains, wheat germ, wild rice, mushrooms, soybeans, milk, yogurt, eggs, broccoli, brussels sprouts, and spinach. Flours and cereals are often fortified with riboflavin.

Riboflavin is destroyed by light, so food should be stored away from light to protect its riboflavin content. While riboflavin is not destroyed by heat, it can be lost in water when foods are boiled or soaked.

Available Forms:

Riboflavin is generally included in multivitamins and B-complex vitamins, and comes individually in 25-, 50-, and 100-mg tablets.

How to Take It:

As with all medicines, check with a healthcare provider before giving riboflavin supplements to a child.

Daily recommendations for dietary riboflavin are listed below.

Pediatric

Infants birth - 6 months: 0.3 mg (adequate intake)
Infants 7 - 12 months: 0.4 mg (adequate intake)
Children 1 - 3 years: 0.5 mg (RDA)
Children 4 - 8 years: 0.6 mg (RDA)
Children 9 - 13 years: 0.9 mg (RDA)
Males 14 - 18 years: 1.3 mg (RDA)
Females 14 - 18 years: 1 mg (RDA)

Adult

Males 19 years and older: 1.3 mg (RDA)
Females 19 years and older: 1.1 mg (RDA)
Pregnant females: 1.4 mg (RDA)
Breastfeeding females: 1.6 mg (RDA)

Riboflavin is best absorbed when taken between meals.

People who do not eat a balanced diet every day may benefit from taking a multivitamin and mineral complex. A good rule of thumb when selecting a multivitamin is to look for one that includes 100 - 300% of the daily value for all essential vitamins and minerals. You should check with a knowledgeable health care provider if you are considering supplement doses higher than twice the daily value.

Precautions:

Because of the potential for side effects and interactions with medications, you should take dietary supplements only under the supervision of a knowledgeable health care provider.

Riboflavin is generally considered safe, even at high doses. However, because doses above 10 mg per day may cause eye damage from the sun, people who take high doses should wear sunglasses that protect their eyes from ultraviolet light.

Riboflavin does not appear to cause any serious side effects. Very high doses may cause itching, numbness, burning or prickling sensations, yellow or orange urine, and sensitivity to light.

Taking any one of the B complex vitamins individually for a long period of time can result in an imbalance of the other B vitamins. For this reason, it is generally important to take a B complex vitamin with any single B vitamin.

Possible Interactions:

If you are currently being treated with any of the following medications, you should not use vitamin B2 supplements without first talking to your health care provider.

Anticholinergic Drugs -- Used to treat a variety of conditions, including gastrointestinal spasms, asthma, depression, and motion sickness, these drugs may inhibit the body's ability to absorb riboflavin.

Tetracycline -- Riboflavin interferes with the absorption and effectiveness of tetracycline, an antibiotic. (All vitamin B complex supplements act in this way.) You should take riboflavin at a different time during the day from when you take tetracycline.

Tricyclic Antidepressants -- Tricyclic antidepressants may reduce levels of riboflavin in the body. In addition to raising levels of the vitamin in the body, taking riboflavin may also improve the effects of these antidepressants. They include:

Imipramine (Tofranil)
Desimpramine (Norpramin)
Amitriptyline (Elavil)
Nortriptyline (Pamelor)

Antipsychotic Medications -- Antipsychotic medications called phenothiazines (such as chlorpromazine or Thorazine) may lower riboflavin levels.

Doxorubicin -- Riboflavin may deactivate doxorubicin, a medication used for the treatment of certain cancers. In addition, doxorubicin may deplete levels of riboflavin in the body. Your doctor will let you know whether you need to take a riboflavin supplement or not.

Methotrexate -- Methotrexate, a medication used to treat cancer and autoimmune diseases such as rheumatoid arthritis, can inhibit the body from using riboflavin.

Phenytoin -- Phenytoin (Dilantin), a medication used to control epileptic seizures, may affect riboflavin levels in the body.

Probenecid -- This medication used for gout may decrease the absorption of riboflavin from the digestive tract and increase the excretion in the urine.

Thiazide Diuretics -- Diuretics (water pills) that belong to a class known as thiazides, such as hydrochlorothiazide, may cause you to excrete more riboflavin in your urine.

Supporting Research:

Adelekan DA, Thurnham DI, Adekile AD. Reduced antioxidant capacity in paediatric patients with homozygous sickle cell disease. Eur J Clin Nutr. 1989;43(9):609-614.

Antoon AY, Donovan DK. Burn Injuries. In: Behrman RE, Kliegman RM, Jenson HB, eds. Nelson Textbook of Pediatrics. Philadelphia, Pa: W.B. Saunders Company; 2000:287-294.

Bell, IR, Edman JS, Morrow FD, et al. Brief communication. Vitamin B1, B2, and B6 augmentation of tricyclic antidepressant treatment in geriatric depression with cognitive dysfunction. J Am Coll Nutr. 1992;11(2):159-163.

Bomgaars L, Gunawardena S, Kelley SE, Ramu A. The inactivation of doxorubicin by long ultraviolet light. Cancer Chemother Pharmacol. 1997;40(6):506-512.

Bruno EJ Jr, Ziegenfuss TN. Water-soluble vitamins: research update. Curr Sports Med Rep. 2005 Aug;4(4):207-13. Review.

Cumming RG, Mitchell P, Smith W. Diet and cataract: the Blue Mountains Eye Study.Ophthalmology. 2000;107(3):450-456.

Fishman SM, Christian P, West KP. The role of vitamins in the prevention and control of anaemia. [Review]. Public Health Nutr. 2000;3(2):125-150.

Gartside PS, Glueck CJ. The important role of modifiable dietary and behavioral characteristics in the causation and prevention of coronary heart disease hospitalization and mortality: the prospective NHANES I follow-up study. J Am Coll Nutr. 1995;14(1):71-79.

Head KA. Natural therapies for ocular disorders, part two: cataracts and glaucoma. [Review]. Altern Med Rev. 2001;6(2):141-166.

Hill MJ. Intestinal flora and endogenous vitamin synthesis. Eur J Cancer Prev. 1997;6(Suppl 1):S43-45.

Jacques PF, Chylack LT Jr, Hankinson SE, et al. Long-term nutrient intake and early age-related nuclear lens opacities. Arch Ophthalmol. 2001;119(7):1009-1019.

Kuzniarz M, Mitchell P, Cumming RG, Flood VM. Use of vitamin supplements and cataract: the Blue Mountains Eye Study. Am J Ophthalmol. 2001;132(1):19-26.

Lewis JA, Baer MT, Laufer MA. Urinary riboflavin and creatinine excretion in children treated with anticonvulsant drugs [letter]. Am J Dis Child. 1975;129:394.

Magis D, Ambrosini A, Sandor P, Jacquy J, Laloux P, Schoenen J. A randomized double-blind placebo-controlled trial of thioctic acid in migraine prophylaxis. Headache. 2007 Jan;47(1):52-7.

Mauskop A. Alternative therapies in headache. Is there a role? [Review]. Med Clin North Am. 2001;85(4):1077-1084.

National Academy of Science. Recommended Daily Allowances. Accessed on August 1, 2007.

Nutrients and Nutritional Agents. In: Kastrup EK, Hines Burnham T, Short RM, et al, eds. Drug Facts and Comparisons. St. Louis, Mo: Facts and Comparisons; 2000:4-5.

Omray A. Evaluation of pharmacokinetic parameters of tetracylcine hydrochloride upon oral administration with vitamin C and vitamin B complex. Hindustan Antibiot Bull. 1981;23(VI):33-37.

Parks OW. Photodegredation of sulfa drugs by fluorescent light. J Assoc Off Anal Chem. 1985;68(6):1232-1234.

Pinto JT, Rivlin RS. Drugs that promote renal excretion of riboflavin. Drug Nutr Interact. 1987;5(3):143-151.

Ramu A, Mehta MM, Leaseburg T, Aleksic A. The enhancement of riboflavin-mediated photo-oxidation of doxorubicin by histidine and urocanic acid. Cancer Chemother Pharmacol. 2001;47(4):338-346.

Rock CL, Vasantharajan S. Vitamin status of eating disorder patients: Relationship to clinical indices and effect of treatment. Int J Eating Disord. 1995;18:257-262.

Schoenen J, Jacquy J, Lenaerts M. Effectiveness of high-dose riboflavin in migraneprophilaxis. A randomized controlled trial. Neurology. 1998;50:466-470.

Silberstein SD, Goadsby PJ, Lipton RB. Management of migraine: an algorithmic approach. [Review]. Neurology. 2000;55(9 Suppl 2):S46-52.

Alternative Names: Riboflavin

Review Date: 8/28/2007
Reviewed By: Steven D. Ehrlich, N.M.D., private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

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