Is 1000 IU of vitamin D a day safe?
1,000 IU (25 micrograms) of vitamin D is within the adult upper limit of 4,000 IU (100 micrograms) a day. The adult RDA is 600 IU (15 micrograms) a day, or 800 IU (20 micrograms) over age 70.
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 IU (25 micrograms) of vitamin D is within the NHS guidance of 100 micrograms (4,000 IU) a day. In the UK, adults need 10 micrograms (400 IU) a day.
The figures
| US (NIH) | UK (NHS) | |
|---|---|---|
| Amount checked | 1,000 IU (25 mcg) | |
| Answer | Within the upper limit | Within NHS guidance |
| Compared with | 4,000 IU (100 micrograms) a day | 100 micrograms (4,000 IU) a day |
| Share of the limit | 25% of the limit | 25% of the limit |
| Adults need | 600 IU (15 micrograms) a day, or 800 IU (20 micrograms) over age 70 | 10 micrograms (400 IU) a day |
Good to know
- The NHS advises everyone to consider 10 micrograms a day in autumn and winter.
Quick answers
- Is 1000 IU of vitamin D a day safe?
- 1,000 IU (25 micrograms) of vitamin D is within the adult upper limit of 4,000 IU (100 micrograms) a day. The adult RDA is 600 IU (15 micrograms) a day, or 800 IU (20 micrograms) over age 70.
- What does the NHS say about 1,000 IU of vitamin D?
- 1,000 IU (25 micrograms) of vitamin D is within the NHS guidance of 100 micrograms (4,000 IU) a day. In the UK, adults need 10 micrograms (400 IU) a day.
- What is the upper limit for vitamin D?
- US: 4,000 IU (100 micrograms) a day. UK (NHS): 100 micrograms (4,000 IU) a day.
Sources
- NIH Office of Dietary Supplements fact sheet
https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/ - NHS vitamins and minerals guidance
https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
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More on vitamin D
- Vitamin D: what it does and how much you need
- Is 5000 IU of vitamin D too much?
- Is 10,000 IU of vitamin D safe?
- Is 2000 IU of vitamin D a day safe?