Is 18 mg of iron a day safe?
18 milligrams of iron is within the adult upper limit of 45 milligrams a day. Adults need 8 milligrams for men, 18 milligrams for women aged 19 to 50, and 8 milligrams for women over 50.
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
18 milligrams of iron is above the NHS guidance of 17 milligrams a day from supplements (unless a doctor has prescribed more). In the UK, adults need 8.7 milligrams a day for men and women over 50, and 14.8 milligrams for women aged 19 to 49. Doctors sometimes advise more for a set time, so check with yours before taking this much.
The figures
| US (NIH) | UK (NHS) | |
|---|---|---|
| Amount checked | 18 mg | |
| Answer | Within the upper limit | Above NHS guidance |
| Compared with | 45 milligrams a day | 17 milligrams a day from supplements |
| Share of the limit | 40% of the limit | 106% of the limit |
| Adults need | 8 milligrams for men, 18 milligrams for women aged 19 to 50, and 8 milligrams for women over 50 | 8.7 milligrams a day for men and women over 50, and 14.8 milligrams for women aged 19 to 49 |
Good to know
- Keep iron supplements well away from children: an accidental overdose is dangerous for them.
Quick answers
- Is 18 mg of iron a day safe?
- 18 milligrams of iron is within the adult upper limit of 45 milligrams a day. Adults need 8 milligrams for men, 18 milligrams for women aged 19 to 50, and 8 milligrams for women over 50.
- What does the NHS say about 18 mg of iron?
- 18 milligrams of iron is above the NHS guidance of 17 milligrams a day from supplements (unless a doctor has prescribed more). In the UK, adults need 8.7 milligrams a day for men and women over 50, and 14.8 milligrams for women aged 19 to 49. Doctors sometimes advise more for a set time, so check with yours before taking this much.
- What is the upper limit for iron?
- US: 45 milligrams a day. UK (NHS): 17 milligrams a day from supplements.
Sources
- NIH Office of Dietary Supplements fact sheet
https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/ - NHS vitamins and minerals guidance
https://www.nhs.uk/conditions/vitamins-and-minerals/iron/
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