Overview
B-vitamin used cosmetically for hair and nail growth.
- Whole-food sources (animal products for fat-soluble and B-complex vitamins; produce for water-soluble vitamins)
- Fortified foods (cereals, dairy, plant milks, nutritional yeast)
- Multivitamins or stand-alone supplements in synthetic or food-derived form
- Capsule or softgel
- Sublingual tablet or liquid
- Methylated active form for sensitive individuals
- Multivitamin matrix
Forms & variants of Biotin (B7)
Different chemical forms of Biotin (B7) behave differently. Browse each form's mechanism, bioavailability, and best-use context.
Mechanism of action
Cofactor for carboxylase enzymes; influences keratin gene expression.
- · Cofactor for carboxylase enzymes
- · influences keratin gene expression
Effects on the body
Organ system effects
Biotin (Hair Dose) supports collagen synthesis, antioxidant defense, or barrier function in skin and integumentary tissues.
Evidence-based benefits
Improves brittle nails
Moderate evidenceHair benefits only in deficiency
Limited evidencePotential side effects
- · Acne with very high dose
- · Interferes with thyroid, troponin labs
Drug interactions
Supplement interactions
- Collagen peptidesProvides amino acid substrate for connective tissue synthesis.
- Vitamin CRequired cofactor for collagen hydroxylation.
No specific avoidances listed.
Dosing & bioavailability
Where to buy
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Third-party testedIndependently verified Biotin (Hair Dose) — look for USP, NSF, or Informed Sport seals on the label for purity and dose accuracy.Biotin (Hair Dose) third party tested NSF
CapsulesPre-measured Biotin (Hair Dose) capsules — easiest for travel and consistent daily dosing without scoops or scales.Biotin (Hair Dose) capsules
PowderBulk unflavored Biotin (Hair Dose) powder — best cost-per-gram and flexible dosing for stacking or mixing into drinks.Biotin (Hair Dose) powder unflavored
Best sellersMost-purchased Biotin (Hair Dose) products on Amazon — a quick way to see what's reviewed widely before you commit.Biotin (Hair Dose) best sellerScientific evidence9Show studiesHide studies
Biotin for brittle nails
Hochman LG, et al.
Open trial in 35 patients with brittle nails.
2.5 mg/day biotin increased nail thickness by 25% on average.
PubMed: Biotin (Hair Dose) — Improves brittle nails
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PubMed: Biotin (Hair Dose) — Hair benefits only in deficiency
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PubMed: Biotin (Hair Dose) — randomized controlled trial
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PubMed: Biotin (Hair Dose) — pharmacokinetics
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PubMed: Biotin (Hair Dose) — dose response
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Google Scholar: Biotin (Hair Dose) — clinical evidence
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