B vitamins - wikipedia B vitamins B vitamins are a class of water - soluble vitamins that play important roles in cell metabolism. Though these vitamins share similar names, they are chemically distinct that often coexist in the same foods. In general, dietary supplements containing all eight are referred to as a vitamin B complex. Individual B vitamin supplements are referred to by the specific number or name of each vitamin : B = thiamine, B = riboflavin, B = niacin, etc. Some are better known by name than number : niacin, pantothenic acid, biotin and folate. Each B vitamin is either a cofactor ( generally a coenzyme ) for key metabolic processes or is a precursor needed to make one. Contents 1 List of B vitamins 2 B vitamin molecular functions 3 B vitamin deficiency 4 B vitamin side effects 5 B vitamin sources 6 B vitamin discovery dates 7 Related compounds 8 References List of B vitamins B number Name Thumbnail description Vitamin B thiamine A coenzyme in the catabolism of sugars and amino acids. Vitamin B riboflavin A precursor of cofactors called FAD and FMN, which are needed for flavoprotein enzyme reactions, including activation of other vitamins Vitamin B niacin ( nicotinic acid ), nicotinamide riboside A precursor of coenzymes called NAD and NADP, which are needed in many metabolic processes. Vitamin B pantothenic acid A precursor of coenzyme A and therefore needed to metabolize many molecules. Vitamin B pyridoxine, pyridoxal, pyridoxamine A coenzyme in many enzymatic reactions in metabolism. Vitamin B biotin A coenzyme for carboxylase enzymes, needed for synthesis of fatty acids and in gluconeogenesis. Vitamin B folate A precursor needed to make, repair, and methylate DNA ; a cofactor in various reactions ; especially important in aiding rapid cell division and growth, such as in infancy and pregnancy. Synthetic folate is known as folic acid. Vitamin B various cobalamins ; commonly cyanocobalamin or methylcobalamin in vitamin supplements A coenzyme involved in the metabolism of every cell of the human body, especially affecting DNA synthesis and regulation, but also fatty acid metabolism and amino acid metabolism. Note : other substances once thought to be vitamins were given numbers in the B - vitamin numbering scheme, but were subsequently discovered to be either not essential for life or manufactured by the body, thus not meeting the two essential qualifiers for a vitamin. See section # Related compounds for numbers 4, 8, 10, 11, and others. B Vitamin Molecular functions Vitamin Name Structure Molecular Function Vitamin B thiamine Thiamine plays a central role in the release of energy from carbohydrates. It is involved in RNA and DNA production, as well as nerve function. Its active form is a coenzyme called thiamine pyrophosphate ( TPP ), which takes part in the conversion of pyruvate to acetyl coenzyme A ( CoA ) in metabolism. Vitamin B riboflavin Riboflavin is involved in release of energy in the electron transport chain, the citric acid cycle, as well as the catabolism of fatty acids ( beta oxidation ). Vitamin B niacin Niacin is composed of two structures : nicotinic acid and nicotinamide. There are two co-enzyme forms of niacin : nicotinamide adenine dinucleotide ( NAD ) and nicotinamide adenine dinucleotide phosphate ( NADP ). Both play an important role in energy transfer reactions in the metabolism of glucose, fat and alcohol. NAD carries hydrogens and their electrons during metabolic reactions, including the pathway from the citric acid cycle to the electron transport chain. NADP is a coenzyme in lipid and nucleic acid synthesis. Vitamin B pantothenic acid Pantothenic acid is involved in the oxidation of fatty acids and carbohydrates. Coenzyme A, which can be synthesised from pantothenic acid, is involved in the synthesis of amino acids, fatty acids, ketone bodies, cholesterol, phospholipids, steroid hormones, neurotransmitters ( such as acetylcholine ), and antibodies. Vitamin B pyridoxine, pyridoxal, pyridoxamine The active form pyridoxal 5 ' - phosphate ( PLP ) ( depicted ) serves as a cofactor in many enzyme reactions mainly in amino acid metabolism including biosynthesis of neurotransmitters. Vitamin B biotin Biotin plays a key role in the metabolism of lipids, proteins and carbohydrates. It is a critical co-enzyme of four carboxylases : acetyl CoA carboxylase, which is involved in the synthesis of fatty acids from acetate ; pyruvate CoA carboxylase, involved in gluconeogenesis ; β - methylcrotonyl CoA carboxylase, involved in the metabolism of leucine ; and propionyl CoA carboxylase, which is involved in the metabolism of energy, amino acids and cholesterol. Vitamin B folate Folate acts as a co-enzyme in the form of tetrahydrofolate ( THF ), which is involved in the transfer of single - carbon units in the metabolism of nucleic acids and amino acids. THF is involved in pyrimidine nucleotide synthesis, so is needed for normal cell division, especially during pregnancy and infancy, which are times of rapid growth. Folate also aids in erythropoiesis, the production of red blood cells. Vitamin B cobalamin Vitamin B is involved in the cellular metabolism of carbohydrates, proteins and lipids. It is essential in the production of blood cells in bone marrow, and for nerve sheaths and proteins. Vitamin B functions as a co-enzyme in intermediary metabolism for the methionine synthase reaction with methylcobalamin, and the methylmalonyl CoA mutase reaction with adenosylcobalamin. B Vitamin deficiency Several named vitamin deficiency diseases may result from the lack of sufficient B vitamins. Deficiencies of other B vitamins result in symptoms that are not part of a named deficiency disease. Vitamin Name Deficiency effects Vitamin B 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 thiamin deficiency can also cause Korsakoff 's syndrome, an irreversible dementia characterized by amnesia and compensatory confabulation. Vitamin B riboflavin Main article : Riboflavin § Deficiency 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. Vitamin B 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 ) D 's : dermatitis, diarrhea, dementia, and death ). Vitamin B pantothenic acid Deficiency can result in acne and paresthesia, although it is uncommon. Vitamin B pyridoxine, pyridoxal, pyridoxamine Main article : Vitamin B6 § Deficiency seborrhoeic dermatitis - like eruptions, pink eye, neurological symptoms ( e.g. epilepsy ) Vitamin B 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. Vitamin B folic acid Deficiency results in a macrocytic anemia, and elevated levels of homocysteine. Deficiency in pregnant women can lead to birth defects. Vitamin B cobalamin Deficiency results in a macrocytic anemia, elevated methylmalonic acid and 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. B Vitamin side effects Because water - soluble B vitamins are eliminated in the urine, taking large doses of certain B vitamins usually only produces transient side - effects. General side effects may include restlessness, nausea and insomnia. These side - effects are almost always caused by dietary supplements and not foodstuffs. Vitamin Name Tolerable Upper Intake Level ( UL ) Harmful effects Vitamin B thiamine None No known toxicity from oral intake. There are some reports of anaphylaxis caused by high - dose thiamin injections into the vein or muscle. However, the doses were greater than the quantity humans can physically absorb from oral intake. Vitamin B riboflavin None. No evidence of toxicity based on limited human and animal studies. The only evidence of adverse effects associated with riboflavin comes from in vitro studies showing the production of reactive oxygen species ( free radicals ) when riboflavin was exposed to intense visible and UV light. Vitamin B niacin U.S. UL = 35 mg as a dietary supplement Intake of 3000 mg / day of nicotinamide and 1500 mg / day of nicotinic acid are associated with nausea, vomiting, and signs and symptoms of liver toxicity. Other effects may include glucose intolerance, and ( reversible ) ocular effects. Additionally, the nicotinic acid form may cause vasodilatory effects, also known as flushing, including redness of the skin, often accompanied by an itching, tingling, or mild burning sensation, which is also often accompanied by pruritus, headaches, and increased intracranial blood flow, and occasionally accompanied by pain. Medical practitioners prescribe recommended doses up to 2000 mg per day of niacin in either immediate - release or slow - release formats, to lower plasma triglycerides and low - density lipiprotein cholesterol. Vitamin B pantothenic acid None No toxicity known Vitamin B pyridoxine, pyridoxal, pyridoxamine U.S. UL = 100 mg / day ; EU UL = 25 mg / day Main article : Vitamin B § Side effects Vitamin B biotin None No toxicity known Vitamin B folic acid 1 mg / day Masks B deficiency, which can lead to permanent neurological damage Vitamin B cobalamin None established. Skin and spinal lesions. Acne - like rash ( causality is not conclusively established ). B Vitamin sources B vitamins are found in whole unprocessed foods. Processed carbohydrates such as sugar and white flour tend to have lower B vitamin than their unprocessed counterparts. For this reason, it is required by law in many countries ( including the United States ) that the B vitamins thiamine, riboflavin, niacin, and folic acid be added back to white flour after processing. This is sometimes called `` Enriched Flour '' on food labels. B vitamins are particularly concentrated in meat such as turkey, tuna and liver. Good sources for B vitamins include legumes ( pulses or beans ), whole grains, potatoes, bananas, chili peppers, tempeh, nutritional yeast, brewer 's yeast, and molasses. Although the yeast used to make beer results in beers being a source of B vitamins, their bioavailability ranges from poor to negative as drinking ethanol inhibits absorption of thiamine ( B ), riboflavin ( B ), niacin ( B ), biotin ( B ), and folic acid ( B ). In addition, each of the preceding studies further emphasizes that elevated consumption of beer and other alcoholic beverages results in a net deficit of those B vitamins and the health risks associated with such deficiencies. The B vitamin is not abundantly available from plant products, making B deficiency a legitimate concern for vegans. Manufacturers of plant - based foods will sometimes report B content, leading to confusion about what sources yield B. The confusion arises because the standard US Pharmacopeia ( USP ) method for measuring the B content does not measure the B directly. Instead, it measures a bacterial response to the food. Chemical variants of the B vitamin found in plant sources are active for bacteria, but can not be used by the human body. This same phenomenon can cause significant over-reporting of B content in other types of foods as well. A popular way of increasing one 's vitamin B intake is through the use of dietary supplements. B vitamins are commonly added to energy drinks, many of which have been marketed with large amounts of B vitamins with claims that this will cause the consumer to `` sail through your day without feeling jittery or tense. '' Some nutritionists have been critical of these claims, pointing out for instance that while B vitamins do `` help unlock the energy in foods, '' most Americans acquire the necessary amounts easily in their diets. Because they are soluble in water, excess B vitamins are generally readily excreted, although individual absorption, use and metabolism may vary... '' The elderly and athletes may need to supplement their intake of B and other B vitamins due to problems in absorption and increased needs for energy production. In cases of severe deficiency, B vitamins, especially B, may also be delivered by injection to reverse deficiencies. Both type 1 and type 2 diabetics may also be advised to supplement thiamine based on high prevalence of low plasma thiamine concentration and increased thiamine clearance associated with diabetes. Also, Vitamin B ( folic acid ) deficiency in early embryo development has been linked to neural tube defects. Thus, women planning to become pregnant are usually encouraged to increase daily dietary folic acid intake and / or take a supplement. B Vitamin discovery dates B number Name Thumbnail description Vitamin B thiamine Casimir Funk discovered thiamine in 1912. Vitamin B riboflavin D.T. Smith and E.G. Hendrick discovered riboflavin in 1926. Max Tishler invented methods for synthesizing it. Vitamin B niacin or nicotinic acid Conrad Elvehjem discovered niacin in 1937. Vitamin B pantothenic acid Roger J. Williams discovered pantothenic acid in 1933. Vitamin B pyridoxine, pyridoxal, pyridoxamine Paul Gyorgy discovered vitamin B in 1934. Vitamin B biotin Dean Burk was a codiscoverer of biotin. Vitamin B folic acid Lucy Wills discovered folic acid in 1933. Vitamin B various cobalamins ; commonly cyanocobalamin or methylcobalamin in vitamin supplements Various scientists over several decades developed our knowledge of vitamin B. Related compounds Many of the following substances have been referred to as vitamins as they were once believed to be vitamins. They are no longer considered as such, and the numbers that were assigned to them now form the `` gaps '' in the true series of B - complex vitamins described above ( e.g., there is no vitamin B ). Some of them, though not essential to humans, are essential in the diets of other organisms ; others have no known nutritional value and may even be toxic under certain conditions. Vitamin B : can refer to the distinct chemicals choline, adenine, or carnitine. Choline is synthesized by the human body, but not sufficiently to maintain good health, and is now considered an essential dietary nutrient. Adenine is a nucleobase synthesized by the human body. Carnitine is an essential dietary nutrient for certain worms, but not for humans. Vitamin B : adenosine monophosphate ( AMP ), also known as adenylic acid. Vitamin B may also refer to inositol. Vitamin B : para-aminobenzoic acid ( pABA or PABA ), a chemical component of the folate molecule produced by plants and bacteria, and found in many foods. It is best known as a UV - blocking sunscreen applied to the skin, and is sometimes taken orally for certain medical conditions. Vitamin B : pteryl - hepta - glutamic acid ( PHGA ; chick growth factor ). Vitamin Bc - conjugate was also found to be identical to PHGA. Vitamin B : orotic acid. Vitamin B : cell proliferant, anti-anemia, rat growth factor, and antitumor pterin phosphate named by Earl R. Norris. Isolated from human urine at 0.33 ppm ( later in blood ), but later abandoned by him as further evidence did not confirm this. He also claimed this was not xanthopterin. Vitamin B : pangamic acid, also known as pangamate. Promoted in various forms as a dietary supplement and drug ; considered unsafe and subject to seizure by the US Food and Drug Administration. Vitamin B : dimethylglycine ( DMG ) is synthesized by the human body from choline. Vitamin B : pseudoscientific name for the poisonous compound amygdalin, also known as the equally pseudoscientific name `` nitrilosides '' despite the fact that it is a single compound. Amygdalin can be found in various plants, but is most commonly extracted from apricot pits and other similar fruit kernels. Amygdalin is hydrolyzed by various intestinal enzymes to form, among other things, hydrogen cyanide, which is toxic to human beings when exposed to a high enough dosage. Some proponents claim that amygdalin is effective in cancer treatment and prevention, despite its toxicity and a severe lack of scientific evidence. Vitamin B : L - carnitine. Vitamin B : carnitine. Vitamin B : myo - inositol, also called `` mouse antialopaecia factor ''. Vitamin B : `` antiperosis factor '', which prevents perosis, a leg disorder, in chicks ; can be replaced by choline and manganese salts. Vitamin B : carnitine. Vitamin B : a type of B other than pyridoxine. Vitamin B : a type of biotin other than d - biotin. Vitamin B : an alternative name for both pABA ( see vitamin B ) and pantothenic acid. References Jump up ^ Fattal - Valevski, A ( 2011 ). `` Thiamin ( vitamin B1 ) ''. Journal of Evidence - Based Complementary & Alternative Medicine. 16 ( 1 ) : 12 -- 20. doi : 10.1177 / 1533210110392941. Jump up ^ `` Riboflavin ''. Alternative Medicine Review. 13 ( 4 ) : 334 -- 340. 2008. PMID 19152481. 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Retrieved 2009 - 06 - 17. ^ Jump up to : National Academy of Sciences. Institute of Medicine. Food and Nutrition Board., ed. ( 1998 ). `` Chapter 9 - Vitamin B '' ( PDF ). Dietary Reference Intakes for Thiamine, Riboflavin, Niacin, Vitamin B, Folate, Vitamin B, Pantothenic Acid, Biotin, and Choline. Washington, D.C. : National Academy Press. p. 346. ISBN 0 - 309 - 06411 - 2. Archived from the original on 11 October 2010. Retrieved 2010 - 09 - 23. Jump up ^ Dupré, A ; Albarel, N ; Bonafe, JL ; Christol, B ; Lassere, J ( 1979 ). `` Vitamin B - 12 induced acnes ''. Cutis ; cutaneous medicine for the practitioner. 24 ( 2 ) : 210 -- 1. PMID 157854. Jump up ^ Stipanuk, M.H. ( 2006 ). Biochemical, physiological, molecular aspects of human nutrition ( 2nd ed. ). St Louis : Saunders Elsevier p. 667 Jump up ^ Winklera, C ; B. Wirleitnera ; K. Schroecksnadela ; H. Schennachb ; D. Fuchs ( September 2005 ). `` Beer down - regulates activated peripheral blood mononuclear cells in vitro ''. 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The Encyclopedia of Vitamins, Minerals, and Supplements. Infobase Publishing. p. 155. ISBN 978 - 1 - 4381 - 2103 - 1. Jump up ^ Roger L. Lundblad ; Fiona Macdonald ( 30 July 2010 ). Handbook of Biochemistry and Molecular Biology ( Fourth ed. ). CRC Press. pp. 251 --. ISBN 978 - 1 - 4200 - 0869 - 2. Jump up ^ Zeisel, SH ; Da Costa, KA ( 2009 ). `` Choline : An essential nutrient for public health ''. Nutrition Reviews. 67 ( 11 ) : 615 -- 23. doi : 10.1111 / j. 1753 - 4887.2009. 00246. x. PMC 2782876. PMID 19906248. Jump up ^ Vera Reader ( 1930 ). `` The assay of vitamin B4 '' ( PDF ). Biochem. J. 24 ( 6 ) : 1827 -- 31. doi : 10.1042 / bj0241827. PMC 1254803. PMID 16744538. ^ Jump up to : Bender, David A. ( 29 January 2009 ). A Dictionary of Food and Nutrition. Oxford University Press. p. 521. ISBN 978 - 0 - 19 - 157975 - 2. ^ Jump up to : Berdanier, Carolyn D. ; Dwyer, Johanna T. ; Feldman, Elaine B. ( 24 August 2007 ). Handbook of Nutrition and Food ( Second ed. ). CRC Press. p. 117. ISBN 978 - 1 - 4200 - 0889 - 0. Jump up ^ `` webmd.com VITAMIN B8 ( INOSITOL ) OVERVIEW INFORMATION ''. ^ Jump up to : `` Vitamin B10 ( Para -- aminobenzoic acid ( PABA ) ) : uses, side effects, interactions and warnings ''. WebMD. WebMD, LLC. Retrieved 24 January 2014. Jump up ^ Capozzi, Vittorio ; Russo, Pasquale ; Dueñas, María Teresa ; López, Paloma ; Spano, Giuseppe ( 2012 ). `` Lactic acid bacteria producing B - group vitamins : a great potential for functional cereals products '' ( PDF ). Applied Microbiology and Biotechnology. 96 ( 6 ) : 1383 -- 1394. doi : 10.1007 / s00253 - 012 - 4440 - 2. ISSN 0175 - 7598. PMID 23093174. ^ Jump up to : `` Para-aminobenzoic acid ''. Medline Plus Medical Encyclopedia. United States National Institutes of Health. Retrieved 24 January 2014. ^ Jump up to : Herbert, Victor ; Subak - Sharpe, Genell J. ( 15 February 1995 ). Total Nutrition : The Only Guide You 'll Ever Need - From The Icahn School of Medicine at Mount Sinai. St. Martin 's Press. p. 98. ISBN 978 - 0 - 312 - 11386 - 5. Jump up ^ `` CPG Sec. 457.100 Pangamic Acid and Pangamic Acid Products Unsafe for Food and Drug Use ''. Compliance Policy Guidance Manual. US Food and Drug Administration. March 1995. Retrieved 25 January 2014. ^ Jump up to : Velisek, Jan ( 24 December 2013 ). The Chemistry of Food. Wiley. p. 398. ISBN 978 - 1 - 118 - 38383 - 4. Jump up ^ Lerner IJ ( February 1984 ). `` The whys of cancer quackery ''. Cancer. 53 ( 3 Suppl ) : 815 -- 9. doi : 10.1002 / 1097 - 0142 ( 19840201 ) 53 : 3 + < 815 : : AID - CNCR2820531334 > 3.0.CO ; 2 - U. PMID 6362828. Jump up ^ Velisek, Jan ( 24 December 2013 ). The Chemistry of Food. Wiley. p. 209. ISBN 978 - 1 - 118 - 38383 - 4. Jump up ^ Bender, David A. ( 11 September 2003 ). Nutritional Biochemistry of the Vitamins. Cambridge University Press. p. 5. ISBN 978 - 1 - 139 - 43773 - 8. Jump up ^ Carter, Herbert E. ; Bhattacharyya, P.K. ; Weidman, Katharine R. ; Fraenkel, G. 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Vitamins ( A11 ) Fat soluble α - Carotene β - Carotene Retinol Tretinoin Ergosterol Ergocalciferol 7 - Dehydrocholesterol Previtamin D Cholecalciferol 25 - hydroxycholecalciferol Calcitriol ( 1, 25 - dihydroxycholecalciferol ) Calcitroic acid Dihydroergocalciferol D analogues Alfacalcidol Dihydrotachysterol Calcipotriol Tacalcitol Paricalcitol Tocopherol Alpha Beta Gamma Delta Tocotrienol Alpha Beta Gamma Delta Tocofersolan Naphthoquinone Phylloquinone ( K ) Menaquinones ( K ) Menadione ( K ) ‡ Menadiol ( K ) Water soluble Thiamine B analogues Acefurtiamine Allithiamine Fursultiamine Octotiamine Prosultiamine Sulbutiamine Riboflavin Niacin Nicotinamide Pantothenic acid Dexpanthenol Pantethine Pyridoxine, Pyridoxal phosphate Pyridoxamine Pyritinol Biotin Folic acid Dihydrofolic acid Folinic acid Levomefolic acid Adenosylcobalamin Cyanocobalamin Hydroxocobalamin Methylcobalamin Choline Ascorbic acid Dehydroascorbic acid Combinations Multivitamins WHO - EM Withdrawn from market Clinical trials : Phase III Never to phase III Malnutrition or nutrition disorders ( E40 -- E68, 260 -- 269 ) Malnutrition Protein - energy malnutrition Kwashiorkor Marasmus Catabolysis Vitamin deficiency B vitamins B : Beriberi / Wernicke -- Korsakoff syndrome ( Wernicke 's encephalopathy Korsakoff 's syndrome ) B : Riboflavin deficiency B : Pellagra ( Niacin deficiency ) B : Pyridoxine deficiency B : Biotin deficiency B : Folate deficiency B : Vitamin B deficiency Other vitamins A : Vitamin A deficiency / Bitot 's spots C : Scurvy D: Vitamin D deficiency / Rickets / Osteomalacia E : Vitamin E deficiency K : Vitamin K deficiency Mineral deficiency Sodium Potassium Magnesium Calcium Iron Zinc Manganese Copper Iodine Chromium Molybdenum Selenium ( Keshan disease ) Overnutrition Overweight Obesity Childhood obesity Obesity hypoventilation syndrome Abdominal obesity Vitamin poisoning Hypervitaminosis A Hypervitaminosis D Hypervitaminosis E Mineral overload see inborn errors of metal metabolism, toxicity NDL : 00576106 Retrieved from `` https://en.wikipedia.org/w/index.php?title=B_vitamins&oldid=837171991 '' Categories : B vitamins Hidden categories : All articles lacking reliable references Articles lacking reliable references from December 2017 All articles with failed verification Articles with failed verification from May 2017 All articles with unsourced statements Articles with unsourced statements from September 2017 Articles with unsourced statements from August 2016 Articles lacking reliable references from August 2016 Articles with unsourced statements from March 2016 Talk Contents About Wikipedia Беларуская Български Català Čeština Cymraeg Dansk Deutsch ދިވެހިބަސް Eesti Español Esperanto Euskara فارسی Français Galego 한국어 हिन्दी Hrvatski Bahasa Indonesia Italiano עברית ქართული Lëtzebuergesch Lietuvių മലയാളം मराठी Bahasa Melayu Nederlands नेपाली 日本 語 Norsk Occitan ଓଡ଼ିଆ ភាសា ខ្មែរ Polski Português Română Русский Scots Simple English Slovenčina Slovenščina Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska தமிழ் Türkçe Українська ئۇيغۇرچە / Uyghurche Tiếng Việt 中文 44 more Edit links This page was last edited on 19 April 2018, at 04 : 47. 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Question: one of the reasons they are so important is that all b vitamins function as
Answer: cell metabolism