Recommended daily allowance, folate

The amount of foHc acid required for daily iatake is estimated based oa the minimum amouat required to maintain a certaia level of semm folate. The recommeaded dietary allowance (RDA) for foHc acid accounts for daily losses and makes allowances for variation ia iadividual aeeds and bioavailabiUty from food sources (85). The U.S. recommended daily allowance for adults is 400 p.g and for pregnant women is 800 ]1 (Table 4). 

Folate is a water-soluble vitamin. The recommended daily allowances (RDAs) of folate for the adult man and woman are 20fJ and 101) pg, respectively. The RDA is defined in the Preface. Folate is critically important for growth, and for this reason it is required in increased amounts during pregnancy (400 pg. The need for dietary folate remains elevated after pregnancy and during lactation because of the Irans-... 

RECOMMENDED DAILY ALLOWANCE. The Food and Nutrition Board (FNB) of the National Research Council (NRC) recommended daily allowances of folacin (folate) are... 

Except during pregnancy and lactation, do not give folic acid in therapeutic doses greater than 0.4 mg/day until pernicious anemia has been ruled out. Do not include daily doses exceeding the Recommended Dietary Allowance in multivitamin preparations if therapeutic amounts are necessary, give folic acid separately. Elderly It may be prudent to consider the status of folate in people older than 65 years of age. 

The lack of hard evidence about the extent of supplementation required in pregnancy prompted the development of a laboratory-based assessment of metabolic turnover, which involved the assay of total daily folate catabolites (along with intact folate) in the urine of pregnant women. The rationale of the procedure was that this catabolic product represents an ineluctable daily loss of folate, the replacement of which should constitute the daily requirement. Correcting for individual variation in catabolite excretion and the bioavailability of dietary folate, the recommended allowances based on this mode of assessment are in close agreement with the latest recommendations of the USA/Canada and FAO/WHO. The data produced by the catabolite-excretion method may provide a useful adjunct to current methods... 

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