If AHAs and BHAs are too much for your skin, PHAs are the gentle alternative worth knowing.
What PHAs are
Polyhydroxy acids (gluconolactone, lactobionic acid) are chemical exfoliants with larger molecules than AHAs. They work mainly on the skin’s surface, so they exfoliate more gently and are less likely to irritate. Many also have humectant, hydrating properties.
Who they’re for
- Sensitive skin and reactive skin
- People recovering from over-exfoliation who still want gentle renewal
- Anyone who finds glycolic or even mandelic acid too strong
How they compare
Think of exfoliation strength as a spectrum: glycolic (strongest) → lactic → mandelic → PHA (gentlest). PHAs trade speed for tolerability.
How to use them
A few nights a week is plenty, like any exfoliating acid. They’re gentle enough for most routines, but the don’t-over-exfoliate rule still applies. Build it in the routine builder and let it flag any clashes.