Is 1000 mcg of iodine too much?
1,000 micrograms of iodine is within the adult upper limit of 1,100 micrograms a day. That is about 6.7 times the adult RDA of 150 micrograms.
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 iodine is above the NHS guidance of 500 micrograms (0.5 milligrams) a day from supplements. In the UK, adults need 140 micrograms a day. Doctors sometimes advise more for a set time, so check with yours before taking this much.
The figures
| US (NIH) | UK (NHS) | |
|---|---|---|
| Amount checked | 1,000 mcg | |
| Answer | Within the upper limit | Above NHS guidance |
| Compared with | 1,100 micrograms a day | 500 micrograms (0.5 milligrams) a day from supplements |
| Share of the limit | 91% of the limit | 200% of the limit |
| Adults need | 150 micrograms a day, or 220 in pregnancy | 140 micrograms a day |
Quick answers
- Is 1000 mcg of iodine too much?
- 1,000 micrograms of iodine is within the adult upper limit of 1,100 micrograms a day. That is about 6.7 times the adult RDA of 150 micrograms.
- What does the NHS say about 1,000 mcg of iodine?
- 1,000 micrograms of iodine is above the NHS guidance of 500 micrograms (0.5 milligrams) a day from supplements. In the UK, adults need 140 micrograms a day. Doctors sometimes advise more for a set time, so check with yours before taking this much.
- What is the upper limit for iodine?
- US: 1,100 micrograms a day. UK (NHS): 500 micrograms (0.5 milligrams) a day from supplements.
Sources
- NIH Office of Dietary Supplements fact sheet
https://ods.od.nih.gov/factsheets/Iodine-HealthProfessional/ - NHS vitamins and minerals guidance
https://www.nhs.uk/conditions/vitamins-and-minerals/iodine/
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