PHA
Also known as: Polyhydroxy acid, gluconolactone, lactobionic acid
What It Does
The gentlest chemical exfoliant. Larger molecular size means slower penetration and less irritation, with added humectant benefits.
Polyhydroxy acids (PHAs) are the newest generation of chemical exfoliants, offering gentler exfoliation than AHAs with added humectant and antioxidant benefits. Common PHAs include gluconolactone and lactobionic acid. They have larger molecular structures than AHAs, which means they penetrate more slowly and cause less irritation.
PHAs exfoliate the skin surface while also attracting and binding water like humectants. They provide antioxidant protection and are suitable for sensitive skin types that cannot tolerate AHAs or retinol. PHAs are particularly popular for rosacea-prone or post-procedure skin because they improve texture without causing irritation.
Japanese skincare has embraced PHAs as a gentler alternative to AHAs. They appear in products for mature or sensitive skin that needs exfoliation without the risk of inflammation. PHAs are often combined with other gentle ingredients like ceramides and niacinamide.
Larger molecules than AHAs penetrate slowly, providing gentle exfoliation. Also act as humectants to bind water and provide antioxidant protection.
The Japanese Context
Increasingly popular in Japanese skincare for sensitive and mature skin. Represents the trend toward gentler exfoliation methods.
Best For
How It's Used
Typical concentration: 2 to 10%
Ingredient Interactions
Side Effects and Cautions
Very well tolerated. Gentler than AHAs. Mild irritation possible. Use sunscreen.
