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Folic acid

Folic acid (N-pteroyl-L-monoglutamic acid) is a widely occurring growth factor having the character of a vitamin. The forms of folic acid which occur naturally are reduced folates in the form of polyglutamates. Folates exist in tissues as at least eight different coenzyme forms and are needed for different metabolic reactions in the body. Prolonged deficiency of folate vitamins result in a condition called megaloblastic anemia, which is completely reversed by treatment with folate. Anemia especially during pregnancy and in the geriatric population was an early indication of a dietary requirement for folate. A major function of folate is to remove one-carbon units from molecules being metabolized and then deliver them to molecules being synthesized. Folate participates in the formation of the nucleic acids. Further, the activity of DNA is controlled, in part, by methylation, and the primary methylating agent of the body (S-adenosylmethionine) is made in a metabolic cycle involving a folate. Many studies have, therefore, focused on the relationship of folate status to cancer susceptibility, especially colorectal adenoma. Subclinical folate deficiency or disorders of folate metabolism have been implicated in the pathogenesis of a variety of disorders ranging from neurological and psychiatric disorders. Absorption of folic acid by the body is facilitated by enzymes associated with the mucosal cell membrane. Absorption primarily occurs in the mucosae of the upper intestine, known as the jejunum and duodenum. Insufficient folic acid in the diet and the inability to absorb folic acid can cause anemia and/or birth defects, namely, anecephaly and spina bifida, the latter resulting in brain development abnormalities and even death. Newborn children of women receiving adequate folic acid in their diet show a lower incidence of spina bifida and anencephaly. Adequate intake of folic acid reduces homocysteine levels in the blood, significantly reducing the risk, particularly in men, of heart attack, stroke and peripheral vascular disease. Women with a high intake of folic acid have been shown to be at much reduced risk of developing colorectal adenomas. Folic acid, also known as pteroylglutamic acid and vitamin B9 or B9, plays an important role in cell division, erythropoiesis and protein synthesis, all of which are processes very important to growing tissues. Folic acid is part of an enzyme complex that changes vitamin B12 into its active form and helps synthesize amino acids into the new DNA required for dividing cells. It is crucial that an adequate level of folic acid be maintained in the body because folic acid plays an especially important physiological role. Dietary sources of folic acid include liver, leafy dark green vegetables, legumes, citrus fruits and juices, and most berries. Folic acid is absorbed primarily in the proximal small bowel, is highly protein-bound, and is stored in the liver.

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