Is 5000 mcg of biotin safe?

5,000 micrograms of biotin (vitamin B7) has no set upper limit. Adults need an adequate intake of 30 micrograms a day.

Checked 28 September 2026 · Sources: NIH Office of Dietary Supplements fact sheet and NHS vitamins and minerals guidance · Adults onlyUS: No upper limit setUK: Above NHS guidance

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

5,000 micrograms of biotin (vitamin B7) is above the NHS guidance of 900 micrograms (0.9 milligrams) a day from supplements. In the UK, adults need no set amount, as a varied diet gives enough. Doctors sometimes advise more for a set time, so check with yours before taking this much.

The figures

US (NIH)UK (NHS)
Amount checked5,000 mcg
AnswerNo upper limit setAbove NHS guidance
Compared withNo upper limit has been set for biotin.900 micrograms (0.9 milligrams) a day from supplements
Share of the limitNo limit to compare556% of the limit
Adults needAn adequate intake of 30 micrograms a dayNo set amount, as a varied diet gives enough

Good to know

Quick answers

Is 5000 mcg of biotin safe?
5,000 micrograms of biotin (vitamin B7) has no set upper limit. Adults need an adequate intake of 30 micrograms a day.
What does the NHS say about 5,000 mcg of biotin (vitamin B7)?
5,000 micrograms of biotin (vitamin B7) is above the NHS guidance of 900 micrograms (0.9 milligrams) a day from supplements. In the UK, adults need no set amount, as a varied diet gives enough. Doctors sometimes advise more for a set time, so check with yours before taking this much.
What is the upper limit for biotin (vitamin B7)?
US: No upper limit has been set for biotin. UK (NHS): 900 micrograms (0.9 milligrams) a day from supplements.

Sources

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