Gluconolactone

Gluconolactone is a type of polyhydroxy acid, or PHA. PHAs are supposed to be as effective as AHAs, but less sensitizing.

Gluconolactone is chemically and functionally similar to AHAs (such as glycolic acid). The significant difference between it and AHAs is that gluconolactone has a larger molecular structure, which limits its ability to penetrate the skin, resulting in less potential for sensitizing side-effects. Supposedly, this reduced absorption into the skin does not hamper their effectiveness.