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hc8meifmdc|20005939267D|healthm_live|health_library|health_library_details|0xfdfff9bd01000000e301000001000100
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Vitamin B-Complex refers to the entire group of water-soluble vitamins with the exception of Vitamin C. Vitamin-B Complex vitamins include: |
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Vitamin B1 (Thiamine) |
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Vitamin B2 (Riboflavin) |
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Vitamin B3 (Niacin) |
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Vitamin B5 (Pantothenic Acid) |
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Vitamin B6 (Pyridoxine) |
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Biotin |
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Folic Acid |
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Vitamin B12 (Cobalamins) | |
The vitamin B-complex refers to all of the known essential water-soluble vitamins except for vitamin C. These include thiamine (vitamin B1), riboflavin (vitamin B2), niacin (vitamin B3), pantothenic acid (vitamin B5), pyridoxine (vitamin B6), biotin, folic acid and the cobalamins (vitamin B12).
What is it Vitamin B?
Each member of the B-complex has a unique structure and performs unique functions in the human body. Vitamins B1, B2, B3, and biotin participate in different aspects of energy production, vitamin B6 is essential for amino acid metabolism, and vitamin B12 and folic acid facilitate steps required for cell division. Each of these vitamins has many additional functions. However, contrary to popular belief, no functions require all B-complex vitamins simultaneously. The B vitamins may be necessary in order to:
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Support and increase the rate of metabolism |
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Maintain healthy skin and muscle tone |
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Enhance immune and nervous system function |
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Promote cell growth and division, including that of the red blood cells that help prevent anemia |
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Reduce the risk of pancreatic cancer - one of the most lethal forms of cancer- when consumed in food, but not when ingested in vitamin tablet form. | |
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Where is it Found?
"Vitamin B" was once thought to be a single nutrient that existed in extracts of rice, liver, or yeast. Researchers later discovered these extracts contained several vitamins, which were given distinguishing numbers. Unfortunately, this has led to an erroneous belief among non-scientists that these vitamins have a special relationship to each other. Further adding to confusion has been the "unofficial" designation of other substances as members of the B-complex, such as choline, inositol, and para-aminobenzoic acid (PABA), even though they are not essential vitamins.
"Vitamin B" was once thought to be a single nutrient that existed in extracts of rice, liver, or yeast. Researchers later discovered these extracts contained several vitamins, which were given distinguishing numbers. Unfortunately, this has led to an erroneous belief among non-scientists that these vitamins have a special relationship to each other. Further adding to confusion has been the "unofficial" designation of other substances as members of the B-complex, such as choline, inositol, and para-aminobenzoic acid (PABA), even though they are not essential vitamins.
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Benefits /Uses
Most multivitamin-mineral products contain the B-complex along with the rest of the essential vitamins and minerals. Since they are more complete than B-complex vitamins alone, multiple vitamin-mineral supplements are recommended to improve overall micronutrient intake and prevent deficiencies.
Each member of the B-complex has a unique structure and performs unique functions in the human body. Vitamins B1, B2, B3, and biotin participate in different aspects of energy production, vitamin B6 is essential for amino acid metabolism, and vitamin B12 and folic acid facilitate steps required for cell division. Each of these vitamins has many additional functions. However, contrary to popular belief, no functions require all B-complex vitamins simultaneously.
Human requirements for members of the B-complex vary considerably—from 3 mcg per day for vitamin B12 to 18 mg per day for vitamin B3 in adult males, for example. Therefore, taking equal amounts of each one—as provided in many B-complex supplements—makes little sense. Furthermore, there is little evidence supporting the use of megadoses of B-complex vitamins to combat everyday stress, boost energy, or control food cravings, unless a person has a deficiency of one or more of them. Again, contrary to popular belief, there is no evidence indicating people should take all B vitamins to avoid an imbalance when one or more individual B vitamin is taken for a specific health condition.
Most multivitamin-mineral products contain the B-complex along with the rest of the essential vitamins and minerals. Since they are more complete than B-complex vitamins alone, multiple vitamin-mineral supplements are recommended to improve overall micronutrient intake and prevent deficiencies.
The deficiency of this vitamin can cause number of diseases which are outlined in the table given below:
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Vitamin |
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Deficiency effects |
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Vitamin B1 |
thiamine |
Deficiency causes beriberi. Symptoms of this disease of the nervous system include weight loss, emotional disturbances, Wernicke's encephalopathy (impaired sensory perception), weakness and pain in the limbs, periods of irregular heartbeat, and edema (swelling of bodily tissues). Heart failure and death may occur in advanced cases. Chronic thiamine deficiency can also cause Korsakoff's syndrome, an irreversible psychosis characterized by amnesia and confabulation. |
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Vitamin B2 |
riboflavin |
Deficiency causes ariboflavinosis. Symptoms may include cheilosis (cracks in the lips), high sensitivity to sunlight, angular cheilitis, glossitis (inflammation of the tongue), seborrheic dermatitis or pseudo-syphilis (particularly affecting the scrotum or labia majora and the mouth), pharyngitis (sore throat), hyperemia, and edema of the pharyngeal and oral mucosa. |
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Vitamin B3 |
niacin |
Deficiency, along with a deficiency of tryptophan causes pellagra. Symptoms include aggression, dermatitis, insomnia, weakness, mental confusion, and diarrhea. In advanced cases, pellagra may lead to dementia and death (the 3(+1) Ds: dermatitis, diarrhea, dementia, and death). |
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Vitamin B5 |
pantothenic acid |
Deficiency can result in acne and paresthesia, although it is uncommon. |
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Vitamin B6 |
pyridoxine |
Deficiency may lead to microcytic anemia (because pyridoxyl phosphate is the cofactor for heme synthesis), depression, dermatitis, high blood pressure (hypertension), water retention, and elevated levels of homocysteine. |
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Vitamin B7 |
biotin |
Deficiency does not typically cause symptoms in adults but may lead to impaired growth and neurological disorders in infants. Multiple carboxylase deficiency, an inborn error of metabolism, can lead to biotin deficiency even when dietary biotin intake is normal. |
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Vitamin B9 |
folic acid |
Deficiency results in a macrocytic anemia, and elevated levels of homocysteine. Deficiency in pregnant women can lead to birth defects. Supplementation is often recommended during pregnancy. Researchers have shown that folic acid might also slow the insidious effects of age on the brain. |
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Vitamin B12 |
cobalamin |
Deficiency results in a macrocytic anemia, elevated homocysteine, peripheral neuropathy, memory loss and other cognitive deficits. It is most likely to occur among elderly people, as absorption through the gut declines with age; the autoimmune disease pernicious anemia is another common cause. It can also cause symptoms of mania and psychosis. In rare extreme cases, paralysis can result. | |
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Dosage
Human requirements for members of the B-complex vary considerably—from 3 mcg per day for vitamin B12 to 18 mg per day for vitamin B3 in adult males, for example. Therefore, taking equal amounts of each one—as provided in many B-complex supplements—makes little sense. Furthermore, there is little evidence supporting the use of megadoses of B-complex vitamins to combat everyday stress, boost energy, or control food cravings, unless a person has a deficiency of one or more of them. Again, contrary to popular belief, there is no evidence indicating people should take all B vitamins to avoid an imbalance when one or more individual B vitamin is taken for a specific health condition.
Possible Side-Effects / Precautions / Possible Interactions
Although most B vitamins are eliminated regularly in the urine, taking large doses of certain B vitamins may produce harmful effects.
Research Studies / References
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"Confronting Pancreatic Cancer". http://www.pancreatica.org. Retrieved 2008-02-08. |
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Schernhammer, E., et al. (June 1, 2007). "Plasma Folate, Vitamin B6, Vitamin B12, and Homocysteine and Pancreatic Cancer Risk in Four Large Cohorts". Cancer Research 67 (11): 5553-60. doi:10.1158/0008-5472.CAN-06-4463. http://cancerres.aacrjournals.org/cgi/content/abstract/67/11/5553. Retrieved 2008-02-08. |
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United Press International (June 1, 2007). "Pancreatic cancer risk cut by B6, B12". UPI.com. http://www.upi.com/Consumer_Health_Daily/Briefing/2007/06/01/pancreatic_cancer_risk_cut_by_b6_b12/3712/. Retrieved 2008-02-08. |
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Vitamins, water soluble at FAQ.org |
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Smith, AD; Smith, SM; de Jager, CA; Whitbread, P; Johnston, C; et al; Agacinski, Grzegorz; Oulhaj, Abderrahim; Bradley, Kevin M. et al. (8 September 2010). "Homocysteine-Lowering by B Vitamins Slows the Rate of Accelerated Brain Atrophy in Mild Cognitive Impairment: A Randomized Controlled Trial". PLoS ONE 5 (9): 12244. doi:10.1371/journal.pone.0012244. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0012244. Retrieved 9 September 2010. |
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Carl Heneghan |
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National Academy of Sciences. Institute of Medicine. Food and Nutrition Board., ed (1998). "Chapter 4 - Thiamin". Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, D.C.: National Academy Press. pp. 58-86. http://www.nal.usda.gov/fnic/DRI//DRI_Thiamin/58-86_150.pdf. Retrieved 2009-06-17. |
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National Academy of Sciences. Institute of Medicine. Food and Nutrition Board., ed (1998). "Chapter 5 - Riboflavin". Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, D.C.: National Academy Press. pp. 87-122. http://www.nal.usda.gov/fnic/DRI//DRI_Thiamin/87-122_150.pdf. Retrieved 2009-06-17. |
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National Academy of Sciences. Institute of Medicine. Food and Nutrition Board., ed (1998). "Chapter 6 - Niacin". Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, D.C.: National Academy Press. pp. 123-149. http://www.nal.usda.gov/fnic/DRI//DRI_Thiamin/123-149_150.pdf. Retrieved 2009-06-17. |
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http://www.rxabbott.com/pdf/niaspan.pdf |
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National Academy of Sciences. Institute of Medicine. Food and Nutrition Board., ed (1998). "Chapter 7 - Vitamin B6". Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, D.C.: National Academy Press. pp. 150-195. http://www.nal.usda.gov/fnic/DRI//DRI_Thiamin/150-195_150.pdf. Retrieved 2009-06-17. | |
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