Supplement reference
Keratin
A source-linked reference on Keratin, evidence, safety and product identity. Sources checked 6 September 2026.
Source and review status
Published sources checked
Sources checked on: 6 September 2026
Qualified clinical review: Pending. This page has not been clinically reviewed.
About this source check
AI-assisted editorial source checking covers the cited material and its stated limits. It is not a systematic review, verification of a supplied product, or clinical sign-off.
Editorial role: InfoAddict. Last material change: 6 September 2026. Next source review: 6 March 2027.
Ingredient and preparation
Keratin is a structural protein; supplement labels may differ by source, hydrolysis, molecular size and accompanying ingredients.
Sources: National Library of Medicine, PubMed
Evidence and limits
A 90-day randomised trial in 50 women tested Cynatine HNS, a branded product combining keratin with vitamins and minerals, and reported better hair and nail measures than placebo. It cannot identify an effect of keratin alone or a different hydrolysate.
Sources: National Library of Medicine, PubMed
Safety and a useful record
The trial does not establish safety for every animal or plant-derived keratin product. Check the source material and full label, particularly when allergy or medicine context matters.
Sources: National Library of Medicine, PubMed, National Center for Complementary and Integrative Health
Record the source, full ingredient list, start date and the specific observation you hoped to follow.
Sources: National Center for Complementary and Integrative Health
Published sources
- A clinical trial to investigate the effect of Cynatine HNS on hair and nail parameters
National Library of Medicine, PubMed. Published 2014; accessed 6 September 2026.
Supports: A 90-day randomised trial in 50 women tested a branded keratin-containing, multi-ingredient product. It does not isolate keratin or apply to every hydrolysate.
- Safe Use of Complementary Health Products and Practices
National Center for Complementary and Integrative Health. Current NCCIH reference; accessed 6 September 2026.
Supports: General safety, interaction and contamination context. It does not establish ingredient-specific benefit.
Change history
| Date | Change | Clinical-review status |
|---|---|---|
| 6 September 2026 | Source-linked reference published | Pending |
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