Beauty
Biotin
Also known as: Vitamin B7, Vitamin H, Biotin (D-Biotin), d-biotin
A water-soluble B vitamin essential for hair, skin, and nail health and serves as a coenzyme in amino acid and glucose metabolism. D-biotin is the naturally active form.
Last reviewed June 2026 · Evidence graded from peer-reviewed research, not editorial opinion. Educational only — not medical advice.
Daily target & upper limit
30 mcg / dayBiotin has an established daily reference intake. See best forms, label synonyms, upper-limit warnings, and top-scoring supplements:
Biotin dosage reference →Primary uses
- Hair health
- Nail strength
- Skin health
- Hair, skin, and nail health
- Glucose metabolism support
- Amino acid metabolism
- Keratin production
- Biotin deficiency prevention
How it works
- Cofactor for keratin production
- Cellular energy
- Fatty acid metabolism
Dosage
- Typical range
- 2500-5000mcg daily
- Timing
- Any time
- With food
- Optional
- Duration
- 3-6 months for hair effects
- Special populations
- Hair loss (if deficient), brittle nails
Forms
- Capsules
- Gummies
- d-biotin· 70/100
Safety
Common side effects
- Acne in some people
Contraindications
- None
Products containing Biotin
Top-scoring supplements in our catalog that list Biotin on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Evidence notes
Popular, but only helps if deficient
Grade B: Some human trials support key claims; further confirmation needed.
Related in Beauty
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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Individual needs and risks vary — consult a professional before starting, stopping, or combining supplements, especially if you are pregnant or nursing, taking medication, or managing a health condition.