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Hair peptides: what the evidence says

Leave-on scalp serums with peptides aim to help hair look thicker. The science is early; expectations should stay realistic.

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Quick answerWeak evidence

Peptide scalp serums are low-risk and easy to try. Human data is limited. They will not reverse medical hair loss; see a dermatologist for that.

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Injectable versions are not covered here. We only cover topical and oral products sold legally as cosmetics or food supplements. Injectable or “research” peptides are not approved for personal use and carry real risks.

Guides

Our pick

Hair pick
The Ordinary

Multi-Peptide Serum for Hair Density

Why we like it: A lightweight leave-on scalp serum that helps hair look thicker and fuller.

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FAQ

Can peptides regrow hair?

No good human evidence that topical peptide serums regrow hair. They may help hair look thicker and fuller with consistent use.

How long to try one?

Give a scalp serum at least 3 months of daily use before you judge.