# Doubling Your Retinol Strength Didn't Double the Results on Skin

_Evidence Level: Moderate · Pordąb I et al., International journal of molecular sciences, DOI 10.3390/ijms27167205_

*Barrier Function and Biophysical Effects of 0.104% and 0.247% Retinol Creams in Mature Facial Skin: A Prospective Study.*

- **Evidence Level**: Moderate
- **Why this grade**: Randomized single-blind trial in 38 women over 12 weeks, though only 28 were in the main comparison and the imaging and biomarker sub-studies had just 5 participants each.
- **Facts**: Design: Randomized Controlled Trial
- **Publication Types**: Journal Article, Randomized Controlled Trial
- **Journal**: International journal of molecular sciences
- **Sample Size**: 38 women aged 40-61 with mature facial skin
- **Authors**: Pordąb I, Cieślawska J, Gackowski M, Kowalczyk MJ, Pawłowska M, Gornowicz-Porowska J, Osmałek T, Marzec M, Nowak I, Kroma-Szal A, Pawlaczyk M
- **Graded and published**: 2026-08-12
- **Last edited**: 2026-09-17
- **Topics**: Skin Aging, Vitamin A, Retinol
- **DOI**: https://doi.org/10.3390/ijms27167205
- **Free full text**: https://pmc.ncbi.nlm.nih.gov/articles/PMC13513334/
- **Original Source**: https://pubmed.ncbi.nlm.nih.gov/42653210/

## Summary

Women aged 40 to 61 used facial creams with either 0.104% or 0.247% retinol for 12 weeks. Both strengths improved hydration, barrier function, skin brightness, pH, and oiliness by about the same amount. The stronger cream smoothed skin better but caused more redness. Firmness and elasticity didn't budge with either, which fits retinol's slow remodeling timeline.

## Practical Takeaway

This study suggests lower-strength retinol may deliver similar barrier benefits with less irritation.

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