The Study
One-year longitudinal study of the stratum corneum proteome of retinol and all-trans-retinoic acid treated human skin: an orchestrated molecular event
This study watched how skin proteins changed over a year when people used special creams. It found that certain molecules in the skin moved up or down after using the creams, but it didn’t prove the creams caused those changes—maybe other things like diet or sun exposure played a role too.
Analysis score
Maximum 36 for a cohort study.
Where the score came from
These skincare ingredients don’t just smooth wrinkles — they turn on your skin’s energy and protein factories first, then fix its protective barrier over time.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 536 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — these changes explain why skin looks smoother, brighter, and more resilient after months of use, even if wrinkles don’t vanish immediately.
- 2At 3 months: 6 glycolytic enzymes and 16 translation factors increased; 14 glycan-degrading enzymes decreased.
- 3At 12 months: filaggrin, involucrin, and calmodulin-like protein 3 stayed high; epidermis thickened.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Scientific Reports
Year
2023
Authors
K. Abed, A. Foucher, D. Bernard, E. Tancrède‐Bohin, N. Cavusoglu
Related Content
Claims (6)
Using tretinoin cream on the skin for one month reduces wrinkles, evens out skin pigmentation, and fades age spots.
Daily use of 0.3% retinol or 0.025% all-trans-retinoic acid on the skin for one year is associated with increased levels of proteins involved in energy production, protein synthesis, and skin barrier formation, and decreased levels of proteins that break down sugar molecules in the outer skin layer.
Topical retinol and retinoic acid reduce the activity of enzymes that break down glycans in the outer layer of skin after three months of use, with retinol having a stronger effect than retinoic acid.
When applied to the skin, retinol and retinoic acid trigger changes in proteins and cellular molecules within three months, but visible structural changes like thickening of the skin layer do not become significant until twelve months.
Applying retinol and retinoic acid to the skin increases the activity of certain metabolic and protein-building molecules in the outer skin layer, reaching highest levels at 3 months and decreasing by 12 months.
Topical retinol and retinoic acid change the expression levels of specific skin barrier proteins and enzymes in a sustained manner, resulting in structural alterations to the outermost layer of the skin.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.