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Vitamin

Biotin (B7)

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Biotin (B7). Coenzyme for carboxylases — popular for hair and nails despite weak data outside true deficiency.

How it works. Cofactor for 5 carboxylases involved in gluconeogenesis, fatty acid synthesis, and amino acid metabolism.

What the research supports. 2 graded claims. Strongest: Reverses hair/nail issues in biotin deficiency (strong).

How much to take. Typical dose: 30 mcg (RDA).

Side effects and interactions. 1 medication interaction listed. Serious: Falsely alters thyroid/troponin lab assays at high dose.

Stacking. Pairs well with Collagen peptides, Vitamin C.

Forms. 1 forms. Pick one to open its profile.

Key studies. 9 studies cited. The strongest are listed with links to PubMed.

Community. Experiences from people who have tried Biotin (B7). Anecdotes are not medical advice.

Biotin (B7). Coenzyme for carboxylases — popular for hair and nails despite weak data outside true deficiency.

Molecular structureC10H16N2O3S · 244.31 g/mol

What it is

Coenzyme for carboxylases — popular for hair and nails despite weak data outside true deficiency.

Also called

Vitamin B7Vitamin H

Food sources

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

Goals

Hair SupportSkin, Hair & NailsGeneral Wellness

How it works

Cofactor for 5 carboxylases involved in gluconeogenesis, fatty acid synthesis, and amino acid metabolism.

Pathways

  • Carboxylase activity
  • Keratin substrate availability

Effects

  • +Reverses hair/nail issues in biotin deficiency supports
  • +hair growth in non-deficient adults supports

What the research supports

Reverses hair/nail issues in biotin deficiencystrong
Improves hair growth in non-deficient adultslimited

Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.

Typical dose
30 mcg (RDA)
TimingConsistent daily timing recommended; split larger doses if GI tolerance is a concern.
With foodOptional
Best formMost evidence is based on the capsule or softgel form.
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Side effects & interactions

Serious

  • Falsely alters thyroid/troponin lab assays at high dose

Medication interactions

Thyroid/troponin lab testsmoderate

Hold 48h before bloodwork.

Check any supplement–medication combination with your pharmacist before starting.

Combines with

Pairs well

  • Collagen peptidesProvides amino acid substrate for connective tissue synthesis.
  • Vitamin CRequired cofactor for collagen hydroxylation.

Key studies

9 studies cited in total.

PubMed: Biotin (B7) — Reverses hair/nail issues in biotin deficiency ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Biotin (B7) and "Reverses hair/nail issues in biotin deficiency". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Biotin (B7) — Improves hair growth in non-deficient adults ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Biotin (B7) and "Improves hair growth in non-deficient adults". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Biotin (B7) — randomized controlled trial ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Biotin (B7) and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

Discussion

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