AHA
AHA (Alpha Hydroxy Acid)
Definition (cosmetic use): A family of water-soluble acids—such as lactic and citric—used at cosmetic levels to promote a smoother-looking surface by encouraging orderly exfoliation. In routines, AHAs are chosen for visible radiance and refined texture; they are distinct from PHAs (larger, often gentler molecules).
How AHAs work (cosmetic context)
- Surface renewal: Supports the natural shedding of dead cells for a brighter, more even look.
- pH matters: Performance and feel depend on pH and total acid profile—not just % on the label.
- Comfort balance: Pairing AHAs with PHAs and humectants can help maintain a comfortable feel.
- Frequency over force: Consistent, calibrated use typically yields a smoother appearance than occasional high-intensity use.
Layering & compatibility
- AM example: AHA step → hydration/treatment serum → light lipid finish → sunscreen.
- Don’t stack aggressively: Avoid combining strong exfoliants in the same session; alternate with PHA days if needed.
- Watch the barrier: If skin feels tight, scale back frequency and emphasize hydration + light lipids.
Used in OUMERE
- No. 9 Daily Chemical Exfoliant — blends lactic and mandelic (AHAs) with PHAs for calibrated renewal.
- UV-R — follow with water-phase hydration and botanical support.
- Serum Bioluminelle — finish with a light lipid layer to preserve comfort.
See also
Scientific Note: OUMERE definitions are cosmetic-science references for educational context and routine design. They are not medical advice.