Biotin (vitamin B7): what it does and how much you need
Biotin (vitamin B7) helps turn the food you eat into energy. Adults need an adequate intake of 30 micrograms a day, and no upper limit has been set. High-dose biotin can upset some blood test results, so tell your doctor or the lab if you take it.
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
In the UK, adults need no set amount, as a varied diet gives enough, and the NHS says up to 900 micrograms (0.9 milligrams) a day from supplements is unlikely to cause harm. High-dose biotin can upset some blood test results, so tell your doctor or the lab if you take it.
How much you need and the upper limit
| US (NIH) | UK (NHS) | |
|---|---|---|
| Adults need | An adequate intake of 30 micrograms a day | No set amount, as a varied diet gives enough |
| Upper limit | No upper limit has been set for biotin. | Up to 900 micrograms (0.9 milligrams) a day from supplements |
The UK figure is the amount the NHS says is unlikely to cause harm. Figures are for adults.
Cautions
- High-dose biotin can upset some blood test results, so tell your doctor or the lab if you take it.
Food sources
- Eggs
- Organ meats
- Fish
- Meat
- Seeds and nuts
- Sweet potatoes
Dose questions
Quick answers
- What does biotin (vitamin B7) do?
- Biotin (vitamin B7) helps turn the food you eat into energy.
- How much biotin (vitamin B7) do adults need?
- Adults need an adequate intake of 30 micrograms a day (US, NIH). In the UK: no set amount, as a varied diet gives enough (NHS).
- What is the upper limit for biotin (vitamin B7)?
- US: No upper limit has been set for biotin. UK (NHS): up to 900 micrograms (0.9 milligrams) a day from supplements is unlikely to cause harm.
- Which foods have biotin (vitamin B7)?
- Eggs, organ meats, fish, meat, seeds and nuts, sweet potatoes.
- What should I watch out for with biotin (vitamin B7)?
- High-dose biotin can upset some blood test results, so tell your doctor or the lab if you take it.
Sources
- NIH Office of Dietary Supplements fact sheet
https://ods.od.nih.gov/factsheets/Biotin-HealthProfessional/ - NHS vitamins and minerals guidance
https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-b/
Ask Supplement Check yourself
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