The Receipt
- 01BHA for pores; AHA for surface.
- 02A few times a week, plus sunscreen.
- 03If it stings, stop.
Education, not a diagnosis. If something changes quickly, hurts, bleeds, or worries you, see a dermatologist.
Skin Files · Exfoliation
AHA vs BHA: which exfoliant is right for your skin?
Glycolic and lactic acid (AHAs) vs salicylic acid (BHA): what each does, which skin types suit them, how often to exfoliate, and how not to overdo it.
- Texture & pores
- Acne & breakouts
- Dark marks & tone
01 · The short version
Chemical exfoliants are the fastest way to smoother-feeling skin, and the fastest way to an irritated, stinging face. Picking the right type helps.
02 · The difference
- AHAs (glycolic, lactic, mandelic) are water-soluble and work on the surface: dullness, roughness, uneven tone.
- BHA (salicylic acid) is oil-soluble and works inside pores: blackheads, clogged pores, oily skin.
03 · Which to choose
Oily or acne-prone with blackheads: start with BHA. Dry, dull or rough: lactic acid. Normal skin with uneven tone: glycolic or lactic. Sensitive skin: low-strength lactic, or skip acids and focus on basics.
04 · How often
Two to three times a week is a common starting point. Increase only if your skin stays comfortable. Stinging, tightness and new redness mean pull back.
05 · Sun sensitivity
AHAs can increase sun sensitivity. The FDA advises daily sun protection while using them and for a week afterwards.
06 · The science
Hydroxy acids loosen the bonds between dead surface cells so they shed more evenly. Concentration and pH determine how strong a product is, more than the acid name alone.
07 · What might help
- AHAs for smoother texture and brightness.limited evidence
- BHA for blackheads and clogged pores.limited evidence
- Daily sunscreen while using AHAs.well-supported
08 · Insufficient evidence
- Daily strong exfoliation for faster results.
- Physical scrubs as an equal alternative; many irritate.
Questions people ask
- Can I use AHA and BHA together?
- Some products combine them. If you use separate products, alternate days at first to avoid irritation.
- Can I use an exfoliating acid with retinol?
- Use them on different nights, especially while your skin is adjusting.
Sources (5)
- Kornhauser A, Coelho SG, Hearing VJ. Applications of hydroxy acids: classification, mechanisms, and photoactivity. Clin Cosmet Investig Dermatol. 2010.
- Arif T. Salicylic acid as a peeling agent: a comprehensive review. Clin Cosmet Investig Dermatol. 2015.
- Sharad J. Glycolic acid peel therapy – a current review. Clin Cosmet Investig Dermatol. 2013.
- U.S. FDA. Alpha hydroxy acids (cosmetic ingredient information).
- Liu H, et al. Topical azelaic acid, salicylic acid, nicotinamide, sulphur, zinc and fruit acid (alpha-hydroxy acid) for acne. Cochrane Database Syst Rev. 2020.