Biotin: The Complete Guide

Written by the Osmotics team · Reviewed by Elena Hart, MD, dermatologist · Last updated

The short answer

Biotin (vitamin B7) supports skin, hair and nails, and in skincare helps maintain a healthy, well-conditioned barrier.

Quick answer: Biotin (vitamin B7) is a conditioning vitamin best known for supporting the look of healthy hair, lashes and nails. In topical skincare it conditions and supports the surface, and it’s the basis of peptide derivatives used in lash and brow care.

What is biotin?

Biotin is a water-soluble B vitamin (vitamin B7) associated with the health of keratin-rich tissues — hair, lashes, brows and nails. In cosmetics it acts as a conditioning ingredient and forms the basis of active derivatives such as Biotinoyl Tripeptide-1, used to support the look of fuller lashes and brows.

What does it do?

  • Conditions — supports the look and feel of healthy skin, lashes and brows.
  • Supports keratin-rich tissue — the basis for lash, brow and nail care.
  • Complements lash/brow peptides — as the foundation of biotin-linked actives.

How to use it

Biotin comes formulated into conditioning treatments and lash/brow products, for daily use per the product’s directions. It layers well with peptides and conditioning actives.

Is it safe?

As a gentle conditioning vitamin it’s generally well tolerated. This guide is general education, not medical advice; individual results vary. Note that topical biotin conditions the surface — it isn’t the same as dietary biotin.

Explore our other conditioning actives in the Ingredient Glossary, or find your match with the skin quiz.

Frequently asked questions

What does biotin do in skincare?

It’s a conditioning vitamin that supports the look of healthy skin, lashes and brows, and forms the basis of lash/brow peptide actives.

Is topical biotin the same as biotin supplements?

No — topical biotin conditions the surface, which is different from dietary biotin taken as a supplement.

Does biotin help lashes and brows?

Biotin-linked actives like Biotinoyl Tripeptide-1 are used to support the look of fuller lashes and brows.

Is biotin safe for sensitive skin?

Yes — it’s a gentle conditioning vitamin generally well tolerated.

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Osmotics formulas that feature this active.

Eye Lash Enhancing Serum Eye Lash Enhancing Serum Eye Lash Enhancing Serum is a prostaglandin-free peptide and biotin lash serum for sparse, brittle las... $48.00

References

  1. Zempleni J, Hassan YI, Wijeratne SS. Biotin and biotinidase deficiency. Expert Review of Endocrinology & Metabolism. 2008;3(6):715–724.

Evidence for topical biotin in skin and hair is limited; most support relates to correcting dietary biotin deficiency rather than topical application.

This guide describes the appearance of skin and is general education, not medical advice; individual results may vary.