Skip to main content

Vitamins

Biotin

Also listed as vitamin B7, vitamin H

A B vitamin that helps hair only if you are deficient, which is rare. In shampoo it rinses away before it can do anything useful.

No real evidenceTypical strength: Small amounts in shampoos and conditioners (rarely disclosed)

What it is

Biotin is a B vitamin the body needs to make keratin. Genuine deficiency (from rare genetic conditions, some medicines, or eating lots of raw egg white) causes hair loss, and correcting it helps.

Most people are not deficient. Added to shampoo or conditioner, biotin sits on the scalp for a minute or two and is rinsed off; there is no evidence it is absorbed in useful amounts or changes hair.

How strong is the evidence?

No real evidence

A systematic review found that every reported case of biotin improving hair or nails involved a deficiency or an underlying disorder, with insufficient evidence for healthy people. There are no controlled trials of topical biotin in shampoo.

What it's used for, checked

Thicker, faster-growing hair (shampoo/conditioner)

Unproven

No trials of topical biotin; rinse-off contact is brief.

Treats hair loss from biotin deficiency

Holds up

True for oral biotin when a deficiency is confirmed, which is uncommon.

Stops pattern hair loss

False

Pattern hair loss is hormonal and genetic; biotin does not address it.

Who should be careful

  • Topical biotin is harmless.
  • If you also take high-dose biotin supplements, tell your clinician before blood tests: biotin can distort results of some thyroid, hormone and heart (troponin) tests.
  • New or sudden hair loss deserves a medical check (thyroid, iron, medications, scalp conditions) rather than a biotin product.

The studies

Every citation is checked against its PubMed record.

  1. A Review of the Use of Biotin for Hair Loss.
    Patel DP, Swink SM, Castelo-Soccio L · Skin Appendage Disord · 2017 · Systematic literature review

    All 18 reported cases where biotin improved hair or nails involved an underlying disorder or deficiency; there was no sufficient evidence for biotin in healthy people.