Is 1000 mcg of folic acid too much?
1,000 micrograms of folate (vitamin B9) is right at the adult upper limit of 1,000 micrograms of folic acid a day from supplements and fortified foods. That is about 4.3 times the adult RDA of 400 micrograms DFE.
General information, not medical advice. Check with a doctor or pharmacist before taking a supplement, especially if you are pregnant or breastfeeding, take any medicine, or are under 18.
In the UK
1,000 micrograms of folate (vitamin B9) is right at the NHS guidance of 1,000 micrograms (1 milligram) of folic acid a day from supplements. In the UK, adults need 200 micrograms a day, plus 400 micrograms of folic acid a day from before pregnancy until week 12.
The figures
| US (NIH) | UK (NHS) | |
|---|---|---|
| Amount checked | 1,000 mcg (1,700 mcg DFE) | |
| Answer | At the upper limit | At NHS guidance |
| Compared with | 1,000 micrograms of folic acid a day from supplements and fortified foods | 1,000 micrograms (1 milligram) of folic acid a day from supplements |
| Share of the limit | 100% of the limit | 100% of the limit |
| Adults need | 400 micrograms DFE a day, or 600 in pregnancy | 200 micrograms a day, plus 400 micrograms of folic acid a day from before pregnancy until week 12 |
Quick answers
- Is 1000 mcg of folic acid too much?
- 1,000 micrograms of folate (vitamin B9) is right at the adult upper limit of 1,000 micrograms of folic acid a day from supplements and fortified foods. That is about 4.3 times the adult RDA of 400 micrograms DFE.
- What does the NHS say about 1,000 mcg of folate (vitamin B9)?
- 1,000 micrograms of folate (vitamin B9) is right at the NHS guidance of 1,000 micrograms (1 milligram) of folic acid a day from supplements. In the UK, adults need 200 micrograms a day, plus 400 micrograms of folic acid a day from before pregnancy until week 12.
- What is the upper limit for folate (vitamin B9)?
- US: 1,000 micrograms of folic acid a day from supplements and fortified foods. UK (NHS): 1,000 micrograms (1 milligram) of folic acid a day from supplements.
Sources
- NIH Office of Dietary Supplements fact sheet
https://ods.od.nih.gov/factsheets/Folate-HealthProfessional/ - NHS vitamins and minerals guidance
https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-b/
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