Vitamins & minerals
Vitamin B7 (Biotin)
Names you may see: biotin D-biotin B7 hair nails
The quick take
Biotin helps enzymes process fats, carbohydrates and proteins. It is often included in hair, skin and nail supplements.
A closer look
What forms will I see on a label?
Labels commonly list biotin or D-biotin, often in micrograms. Check units carefully when comparing high-strength products.
Why people use it
Biotin is widely marketed for hair, skin and nails. These cosmetic goals explain its popularity, but benefits should not be assumed when biotin intake is already adequate.
These are common goals and marketing uses. The evidence section below explains what research supports.
What does the evidence tell us?
Evidence for improving hair or nails in people without deficiency is limited. More biotin does not automatically produce better cosmetic results.
What should I know before using it?
Biotin can interfere with laboratory tests, including some heart and thyroid tests. Tell your clinician and laboratory about its use.
Sources & further reading
NIH Office of Dietary Supplements ↗
Content reviewed: September 30, 2026
General educational information. Follow the product label and seek individual advice when needed.