Is 400 IU of vitamin E safe?
400 IU of vitamin E is within the adult upper limit of 1,000 milligrams a day (about 1,500 IU of natural or 1,100 IU of synthetic vitamin E). That is about 18 times the adult RDA of 15 milligrams (about 22 IU of natural vitamin E).
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
400 IU of vitamin E is within the NHS guidance of 540 milligrams (800 IU) a day from supplements. In the UK, adults need 4 milligrams a day for men and 3 milligrams for women.
The figures
| US (NIH) | UK (NHS) | |
|---|---|---|
| Amount checked | 400 IU (268 mg) | |
| Answer | Within the upper limit | Within NHS guidance |
| Compared with | 1,000 milligrams a day (about 1,500 IU of natural or 1,100 IU of synthetic vitamin E) | 540 milligrams (800 IU) a day from supplements |
| Share of the limit | 36% of the limit | 67% of the limit |
| Adults need | 15 milligrams (about 22 IU of natural vitamin E) a day | 4 milligrams a day for men and 3 milligrams for women |
Good to know
- It is not clear if this is natural or synthetic vitamin E, so the check assumes synthetic, the stricter case.
Quick answers
- Is 400 IU of vitamin E safe?
- 400 IU of vitamin E is within the adult upper limit of 1,000 milligrams a day (about 1,500 IU of natural or 1,100 IU of synthetic vitamin E). That is about 18 times the adult RDA of 15 milligrams (about 22 IU of natural vitamin E).
- What does the NHS say about 400 IU of vitamin E?
- 400 IU of vitamin E is within the NHS guidance of 540 milligrams (800 IU) a day from supplements. In the UK, adults need 4 milligrams a day for men and 3 milligrams for women.
- What is the upper limit for vitamin E?
- US: 1,000 milligrams a day (about 1,500 IU of natural or 1,100 IU of synthetic vitamin E). UK (NHS): 540 milligrams (800 IU) a day from supplements.
Sources
- NIH Office of Dietary Supplements fact sheet
https://ods.od.nih.gov/factsheets/VitaminE-HealthProfessional/ - NHS vitamins and minerals guidance
https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-e/
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