“Chemical exfoliant” covers three genuinely different ingredient families, each suited to a different skin type. Picking the wrong one is a common reason people find exfoliating acids irritating rather than helpful.
For Dry or Sensitive Skin: PHAs
Polyhydroxy acids like gluconolactone have a larger molecular size than AHAs, so they exfoliate more gently and add a hydration benefit on top. They’re the safest starting point for anyone new to chemical exfoliation or prone to irritation.
For Dry, Sun-Damaged, or Textured Skin: AHAs
Glycolic and lactic acid work on the skin’s surface, dissolving the bonds between dead skin cells to improve tone, texture, and the appearance of fine lines. Glycolic acid is the more potent option; lactic acid is gentler and adds hydration.
For Oily or Acne-Prone Skin: BHAs
Salicylic acid is oil-soluble, meaning it can get inside the pore itself rather than just working on the surface — making it the standout choice for blackheads, congestion, and oily texture.
What to Check on Any Exfoliating Acid
- Start at a low concentration — higher isn’t automatically better, especially when building tolerance
- Frequency over strength — two to three times a week is a safer starting cadence than daily use
- Non-negotiable SPF — all exfoliating acids increase sun sensitivity
How to Use Them
Introduce one exfoliating acid at a time, apply to clean, dry skin, and always follow with moisturizer. Avoid combining multiple exfoliating acids or layering them with retinol on the same night while your skin adjusts.
The Bottom Line
The right chemical exfoliant depends on your skin type and main concern, not on picking whichever one is trending: PHAs for sensitive skin, AHAs for texture and dryness, BHAs for oil and congestion.