Keratin and skin

What 2 graded rows on keratin agree on for skin, and where they differ. Counted side by side, never averaged.

Consensus finder Rows from the Keratin page, reviewed Oct 21, 2026 How it decides

What the rows agree on

Each block and row is one graded row from the Keratin page, with its PubMed record.

Supplement

Keratin Choose another

2 rows · 149 people

They agree: both rows found an improvement.

No difference

Improved

Each block is one evidence row, sized by how many people it enrolled, with its grade inside.

From the rows

The best-graded row, grade D, is a randomized trial of 99 people (2025) and found an improvement.

The rows run from 50 to 99 people, published from 2013 to 2025: 2 single studies.

2 improved

Grade DFacial skin aging signs, hair gloss and nail hardness · Improved
RCT · n 99 · 2025 · Healthy women aged 35 to 65 with signs of skin aging (multicenter)
500 mg or 1,000 mg per day · 90 days
Both doses improved skin roughness, wrinkles, moisture, elasticity, gloss of skin, hair and nails, and nail hardness versus placebo; fiber anisotropy and density improved only versus baseline, with a trend versus placebo.
Row on the Keratin page · PubMed 39367631 (opens PubMed)
Grade DSkin moisture, elasticity and wrinkles · Improved
RCT · n 50 · 2013 · Women
2 capsules daily providing 500 mg keratin · 90 days
The keratin formula group showed statistically significant improvements in skin moisture, elasticity, wrinkles and appearance compared with placebo.
Row on the Keratin page · PubMed 23902431 (opens PubMed)