Alpha hydroxy acid (AHA)
Mandelic Acid
INCI: Mandelic Acid·Studied at 5–10% (leave-on)·Moderate evidence
The largest of the common alpha hydroxy acids, derived from bitter almonds and marketed as the gentle option for the appearance of an even tone. Its evidence base is younger and thinner than glycolic or lactic.
Studied for
- ·The appearance of an even, clearer-looking complexion
- ·The look of a smoother surface
- ·The appearance of fewer post-blemish marks
How it’s thought to work
A large AHA molecule that penetrates slowly and is studied for the appearance of a more even surface with less irritation; it raises sun sensitivity, so daytime sunscreen matters.
Layering note
Often kept apart from: retinoids in the same layer for sensitive skin.