Acetyl Hydroxyproline
INCI: ACETYL HYDROXYPROLINE
An amino acid derivative that supports skin barrier function and addresses glycation-related ageing
Best For Skin Types
All, Dry, Sensitive, Mature
Addresses
Usage Frequency
Daily
What Is Acetyl Hydroxyproline?
Acetyl hydroxyproline is a modified form of hydroxyproline, an amino acid naturally present in collagen. It is created by acetylating hydroxyproline, a process that enhances its stability and skin penetration properties. In skincare formulations, it functions as a humectant, emollient and skin conditioner.
The ingredient works at the cellular level to support the skin's structural integrity and barrier function, with emerging evidence suggesting it may also help mitigate certain pathways involved in skin ageing.
How It Works
Acetyl hydroxyproline appears to work through multiple mechanisms. Its humectant properties allow it to bind water molecules and draw moisture into the skin, supporting hydration levels. At a deeper level, research suggests it may inhibit the glycation process—a non-enzymatic reaction between sugars and proteins that leads to collagen crosslinking and skin stiffening.
The ingredient may also upregulate ceramide synthesis by influencing enzymes involved in the skin barrier's lipid production, thereby strengthening the stratum corneum and reducing transepidermal water loss.
Clinical Evidence & References
In vitro and ex vivo studies demonstrate that acetyl hydroxyproline can inhibit advanced glycation end-product formation and reduce specific AGE markers such as carboxymethyl lysine (CML). This suggests potential value in addressing glycation-related skin ageing, though translation to visible skin changes in human subjects requires further investigation.
Research on skin barrier function shows promise, with evidence indicating the ingredient may stimulate ceramide synthesis in reconstructed skin models and alleviate pruritus (itching) in conditions involving barrier compromise. However, clinical trial data in humans remains limited, and further studies are needed to establish efficacy ranges and long-term effects.
Published Research
How to Use
Acetyl hydroxyproline is typically found in serums, moisturisers and specialised treatments. It can be used daily as part of a regular skincare routine. There are no known restrictions on combination with other actives, though as with any new ingredient, introducing it gradually allows you to monitor your skin's response.
Safety & Precautions
Regulatory information
Standardised cosmetic-ingredient identifiers used by regulators.
Show identifiers
- INCI Name
- ACETYL HYDROXYPROLINE
- EC Number
- 251-780-6
- Function
- Emollient, Hair Conditioning, Humectant, Skin Conditioning, Skin Protecting
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