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Ma

Malic Acid

Malic AcidExfoliant

Fruit-derived AHA. Often blended with glycolic and lactic for layered exfoliation across multiple molecule sizes.

What it does

Malic acid is an AHA derived from apples. Larger and slower-penetrating than glycolic, smaller and faster than mandelic. It's almost always seen in blended-acid products rather than as the lead ingredient. The same AHA cautions apply: increases photosensitivity, can compound irritation when stacked with retinoids same-night.

The evidence, graded

strongAHAs and BHAs show texture and brightness improvements in 2–4 weeks. Deeper benefits — acne reduction, fine line softening, pigmentation lightening — take 8–12 weeks of consistent use.Smith 1996 · Journal of the American Academy of Dermatology
emergingAHAs (glycolic, lactic, mandelic) need an acidic pH (typically 3.5–4) to deliver advertised exfoliation. Products with neutral or partially neutralized pH still hydrate but won't drive meaningful keratolysis.Smith 1996 · Journal of the American Academy of Dermatology

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Also known as

apple acid

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