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|Section2= |Section6= |Section7= }} Folic acid or folate is a B vitamin. It is also referred to as vitamin M, vitamin B9, vitamin Bc〔(【引用サイトリンク】title=Definition of vitamin Bc )〕 (or folacin), pteroyl-L-glutamic acid, and pteroyl-L-glutamate. Food supplement manufacturers often use the term ''folate'' for something different from "pure" folic acid: in chemistry, ''folate'' refers to the deprotonated ion, and ''folic acid'' to the neutral molecule—which both coexist in water. The International Union of Pure and Applied Chemistry and the International Union of Biochemistry and Molecular Biology state that folate and folic acid are the preferred synonyms for pteroylglutamate and pteroylglutamic acid, respectively.〔(【引用サイトリンク】title=Folic Acid )〕 ''Folate'' indicates a collection of "folates" that is not chemically well-characterized, including other members of the family of pteroylglutamates, or mixtures of them, having various levels of reduction of the pteridine ring, one-carbon substitutions and different numbers of glutamate residues. Folic acid is synthetically produced, and used in fortified foods and supplements on the theory that it is converted into folate. However, folic acid is a synthetic oxidized form, not significantly found in fresh natural foods. To be used it must be converted to tetrahydrofolate (tetrahydrofolic acid) by dihydrofolate reductase (DHFR). Increasing evidence suggests that this process may be slow in humans. Vitamin B9 is essential for numerous bodily functions. Humans cannot synthesize folates ''de novo''; therefore, folic acid has to be supplied through the diet to meet their daily requirements. The human body needs folate to synthesize DNA, repair DNA, and methylate DNA as well as to act as a cofactor in certain biological reactions. It is especially important in aiding rapid cell division and growth, such as in infancy and pregnancy. Children and adults both require folate to produce healthy red blood cells and prevent anemia.〔(【引用サイトリンク】 publisher = Office of Dietary Supplements, National Institutes of Health )〕 Folate and folic acid derive their names from the Latin word ''folium'', which means "leaf". Folates occur naturally in many foods and, among plants, are especially plentiful in dark green leafy vegetables. A lack of dietary folates can lead to folate deficiency. A complete lack of dietary folate takes months before deficiency develops as normal individuals have about 500–20,000 micrograms ( µg) of folate in body stores.〔National Health Service U.K., "Anaemia, vitamin B12 or folate deficiency – Causes" http://www.nhs.uk/Conditions/Anaemia-vitamin-B12-and-folate-deficiency/Pages/Causes.aspx〕 This deficiency can result in many health problems, the most notable one being neural tube defects in developing embryos—a relatively rare birth defect affecting 300,000 (0.2%) births globally each year and 3,000 pregnancies in the United States each year. Common symptoms of folate deficiency include diarrhea, macrocytic anemia with weakness or shortness of breath, nerve damage with weakness and limb numbness (peripheral neuropathy), pregnancy complications, mental confusion, forgetfulness or other cognitive deficits, mental depression, sore or swollen tongue, peptic or mouth ulcers, headaches, heart palpitations, irritability, and behavioral disorders. Low levels of folate can also lead to ] accumulation.〔 Low levels of folate have been associated with specific cancers.〔 However, it is not clear whether consuming recommended (or higher) amounts of folic acid—from foods or in supplements—can lower cancer risk in some people.〔(【引用サイトリンク】title=Folic Acid )〕 ==Health benefits and risks== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「folic acid」の詳細全文を読む スポンサード リンク
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