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Check folate intake vs RDA — see mcg DFE/day, % of RDA and food sources.
Check folate intake vs RDA — see mcg DFE/day, % of RDA and food sources.
Enter values above and click Calculate — results will appear here with the formula explained.
Folate RDA is 400 mcg DFE daily for adults 19+ (600 pregnancy, 500 lactation), where DFE (dietary folate equivalents) corrects for folic acid's 1.7× superior bioavailability: 1 mcg food folate = 1 DFE, but 1 mcg folic acid (fortified/supplement, taken with food) = 1.7 DFE. This calculator checks intake as percent of RDA.
Food hierarchy: lentils (~180 mcg DFE per half cup cooked), spinach, asparagus, Brussels sprouts, beans and fortified grains lead; a bowl of fortified cereal alone can supply 400+ mcg DFE. Average diets land near 300–450 mcg — borderline by design, which is why fortification programs exist.
Pregnancy is the critical window: adequate periconceptional folate (400–800 mcg folic acid daily starting 1–3 months before conception) cuts neural-tube-defect risk ~70%. Because half of pregnancies are unplanned, fortification plus routine supplementation for anyone who could conceive beats reactive dosing after a positive test.
The B12 masking trap: high folic acid corrects megaloblastic anemia while B12-driven neurologic damage progresses silently — the classic reason to check B12 before high-dose folate, especially in older adults and vegans. Fortification debates center partly on this masking risk at population scale.
Upper limit (1,000 mcg folic acid from fortified/supplements; food folate uncapped) guards against masking and unmetabolized-folic-acid concerns, not acute toxicity. MTHFR polymorphisms alter folate metabolism efficiency for a minority — methylfolate supplements bypass the affected step, though clinical advantage over folic acid remains debated outside pregnancy protocols.
This is general information: anemia with neurologic symptoms, pregnancy planning and antifolate medications (methotrexate, some antiepileptics) all warrant clinician-managed dosing, not calculator reassurance.
Check folate intake vs RDA — see mcg DFE/day, % of RDA and food sources. Formula: RDA: 400 mcg DFE 19+ (600 pregnancy, 500 lactation).
Folate RDA is 400 mcg DFE daily for adults 19+ (600 pregnancy, 500 lactation), where DFE (dietary folate equivalents) corrects for folic acid's 1.7× superior bioavailability: 1 mcg food folate = 1 DFE, but 1 mcg folic acid (fortified/supplement, taken with food) = 1.7 DFE. This calculator checks intake as percent of RDA.
Food hierarchy: lentils (~180 mcg DFE per half cup cooked), spinach, asparagus, Brussels sprouts, beans and fortified grains lead; a bowl of fortified cereal alone can supply 400+ mcg DFE. Average diets land near 300–450 mcg — borderline by design, which is why fortification programs exist.
Pregnancy is the critical window: adequate periconceptional folate (400–800 mcg folic acid daily starting 1–3 months before conception) cuts neural-tube-defect risk ~70%. Because half of pregnancies are unplanned, fortification plus routine supplementation for anyone who could conceive beats reactive dosing after a positive test.
The B12 masking trap: high folic acid corrects megaloblastic anemia while B12-driven neurologic damage progresses silently — the classic reason to check B12 before high-dose folate, especially in older adults and vegans. Fortification debates center partly on this masking risk at population scale.
Upper limit (1,000 mcg folic acid from fortified/supplements; food folate uncapped) guards against masking and unmetabolized-folic-acid concerns, not acute toxicity. MTHFR polymorphisms alter folate metabolism efficiency for a minority — methylfolate supplements bypass the affected step, though clinical advantage over folic acid remains debated outside pregnancy protocols.
This is general information: anemia with neurologic symptoms, pregnancy planning and antifolate medications (methotrexate, some antiepileptics) all warrant clinician-managed dosing, not calculator reassurance.
With 350 mcg DFE, not pregnant: 87.5% of the 400 mcg RDA — add half a cup of lentils (180 mcg) to exceed 130%. Pregnant at the same intake: only 58% of 600 — supplement becomes non-optional.
Last reviewed: September 2026 · Report an error