OnePin Peptide Library · Hair
Biotin
Vitamin B7 · Vitamin H · D-Biotin
Biotin (vitamin B7) is a water-soluble B-vitamin that acts as a coenzyme for carboxylase enzymes involved in fatty acid synthesis, amino acid metabolism, and gluconeogenesis - processes relevant to keratin production and the health of skin, hair, and nails. It is one of the most heavily marketed hair-growth supplements.
Daily. If you take high-dose biotin, stop several days before bloodwork and tell your clinician (assay interference).
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
Biotin supports hair primarily as a metabolic cofactor:
Carboxylase Coenzyme
Biotin is the essential cofactor for five carboxylases (e.g., acetyl-CoA carboxylase, pyruvate carboxylase). These drive fatty acid synthesis, branched-chain amino acid catabolism, and gluconeogenesis - pathways that supply substrates for rapidly dividing follicle keratinocytes.
Keratin Production
Adequate biotin supports normal keratin infrastructure in hair and nails. Deficiency impairs this and produces hair thinning/loss, brittle nails, and dermatitis.
Deficiency-Correction Model
The well-supported effect is repletion - reversing hair/nail changes in people who are actually biotin-deficient. In biotin-replete individuals, adding more biotin does not have a clear mechanism to further accelerate hair growth.
What to expect
Weeks 1-4: no visible change.
Weeks 4-12: nail/hair improvement in deficiency states.
Months 3-6: sustained improvement only where deficiency was the cause.
Evidence
Interactions & stacking
What's safe to combine, and what belongs in a separate pin.
Keep separate
Side effects & safety
Commonly reported
- Generally none (water-soluble, excess excreted)
- Rare mild GI upset or acne reports at very high doses
Less common & notes
- No established toxicity, but high doses cause clinically significant laboratory test interference.
- This is the main safety concern.
Pharmacokinetics
Storage. Store at room temperature, cool and dry, away from light.
Regulatory status
Dietary supplement (US, DSHEA). Adequate Intake ~30mcg/day for adults. No established Tolerable Upper Limit, but high doses affect lab testing.
Put it to work
Calculate, log & track
Open Biotin straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open Biotin in the app →Go deeper
The guide & community
The complete Biotin walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
Join the community ↗