Health Reference LibraryHow much folate should I take, and how much is too much?
This entry is part of the Nutri Tailor Health Reference Library — cited research on supplements, nutrients and adjacent areas of health.
Summary
Most adults get the 200 microgram reference intake from greens, pulses and fortified cereal and need no supplement. The two clear cases are pregnancy and a tested low level. If you are trying to conceive or are pregnant, the advice with the evidence behind it is 400 micrograms of folic acid a day from before conception to 12 weeks, and some women are advised a higher dose by their GP or midwife. A low result is usually corrected with 400 to 1000 micrograms of methylfolate a day for eight to twelve weeks, then a retest. The NHS limit is 1 mg a day, because more can hide a B12 deficiency while nerve damage continues, so B12 is checked first.
Dose calculator: capsules to reach your folate target
Enter the daily amount of folate you are aiming for and see how many servings of each Nutri Tailor product reach it. Nothing you enter leaves this device. No AI is used.
This tool does arithmetic on the label figures. It is not personal dosing advice and it knows nothing about your history or blood results. The reference intake, the safe upper guide and the trial doses are on this page; talk to your GP or a registered nutritional therapist before changing what you take.
Effective dose
The reference intake is 200 micrograms a day for adults; in pregnancy the NHS advises 400 micrograms of folic acid a day from before conception until the twelfth week. Most adults get the 200 micrograms from leafy greens, pulses and fortified cereal and need no supplement. The two clear cases are pregnancy and a tested low level. If you are trying to conceive or are pregnant, the advice that has the evidence behind it is 400 micrograms of folic acid a day from before conception to 12 weeks; some women are advised a higher dose by their GP or midwife, and that decision is theirs. Methylfolate (5-MTHF) is the active form and is what a low folate result on a blood test is usually corrected with at 400 to 1000 micrograms a day for eight to twelve weeks, then a retest.
Safety profile
How much is too much: the NHS says more than 1 mg (1000 micrograms) a day of folic acid from supplements could be harmful, because it can hide a B12 deficiency until nerve damage has started. Folate itself is not toxic, but folic acid above 1000 micrograms a day can correct the blood count in someone who is actually short of B12 while the nerve damage from low B12 continues, which is why the NHS sets that limit and why B12 should be checked before a high folate dose is started. The 1000 microgram capsule is a correction dose, not a daily habit, and it sits above the pregnancy dose, so in pregnancy it is only for those told to take it. The B12 and folate combination avoids the masking problem by supplying both.
Guideline positions
NHS vitamins and minerals guidance for folate. NIH Office of Dietary Supplements fact sheet for folate where one exists. The trial doses quoted above are from the sources listed on this page.
Practical framework
Capsules to reach the dose, from the Nutri Tailor range, all made in the UK: [methylfolate capsules](/products/methyltetrahydrofolate), 1000 micrograms of 5-MTHF per capsule, one a day for a correction course; [B12 and folate capsules](/products/b12-and-folate), 1000 micrograms of methylfolate with 1000 micrograms of methylcobalamin per capsule, the pairing that avoids masking a low B12. To read your own result against the UK ranges, use the free blood test result interpreter. This is a summary of published research, not personal health advice. Talk to your GP or a registered nutritional therapist before changing what you take, especially if you are pregnant, have a diagnosed condition or are under ongoing care.
Common misconceptions
That more folate works faster: above the doses the trials used there is no extra effect, only more side effects. That the front of the bottle states the dose: read the per capsule figure and the serving size on the back. That the NHS figure is a toxic threshold: it is the level below which harm is unlikely, which is a different thing.
Sources
- 2020. B vitamins and folic acid. NHS.
- 2023. Vitamins, supplements and nutrition in pregnancy. NHS.