Folate metabolism and requirements

Folate functions in multiple coenzyme forms in acceptance, redox processing and transfer of one-carbon units, including nucleotides and certain amino acids, Folate-requiring metabolic processes are influenced by folate intake , intake of other essential nutrients, including vitamins B-12 and B-6, and at least one common genetic polymorphism, Estimates of folate requirements have been based on intakes associated with maintenance of normal plasma an d erythrocyte folate concentrations and functional tests that reflect abnor malities in folate-dependent reactions, Dietary Reference Intakes for folat e that have been developed recently are based primarily on metabolic studie s in which erythrocyte folate concentration was considered the major indica tor of adequacy. For adults greater than or equal to 19 y, the Recommended Dietary Allowance (RDA) is 400 mu g/d of dietary folate equivalents (DFE); for lactating and pregnant women, the RDAs include an additional 100 and 20 0 mu g of DFE/d, respectively.