For your skin
Exfoliates the surface of your skin to smooth rough texture and fade dullness. The strongest of the AHAs, so start slow.
Want the science? Keep reading ↓Mechanism of action
Smallest alpha hydroxy acid; loosens corneocyte bonds in the stratum corneum to accelerate desquamation.
Why we tier this strong
6 cited papers across 2 countries. Multiple positive efficacy results plus regulatory backing. Clears our published bar (Strong = 15+ studies with multiple randomized controlled trials (RCTs), or a single large longitudinal cohort).
Layering matrix
- Retinolhigh
Retinol + glycolic acid is a classic barrier-buster. Use on different nights.
- Tretinoinhigh
Tretinoin + glycolic acid causes significant barrier disruption. Never layer.
- Adapalenemedium
Adapalene + glycolic acid can over-exfoliate. Alternate nights.
- Salicylic Acidmedium
AHA + BHA stacking risks over-exfoliation. Use a pre-formulated AHA/BHA product or alternate days.
Read the research
- K-Beauty Acids vs. Western Acids: The Actual DifferencesNot all chemical exfoliants are the same. Here's how the formulations diverge and which to reach for.5 min read · Uneven Texture
- How to Layer Actives Without Destroying Your BarrierA working guide to the fifteen most common ingredient conflicts: which to separate, which to alternate, and which to stop worrying about.6 min read · Sensitive / Irritated
- Your Skin Needs 4 Weeks: Here's What That's Actually AboutThe cell-turnover cycle explains why two-week before-and-afters are usually marketing, and what's actually happening at weeks one, two, four, and eight.5 min read · Acne
Compare with
Cited research
Liu H et al., Topical agents for acne (covers AHA / fruit-acid arm), Cochrane Database of Systematic Reviews 2020;5:CD011368 — conclusion: clinical benefit is unclear
Sarkar R et al., Comparative Evaluation of Efficacy and Tolerability of Glycolic Acid, Salicylic-Mandelic Acid, and Phytic Acid Combination Peels in Melasma, Dermatologic Surgery 2016;42(3):384-391 — 35% glycolic acid and salicylic-mandelic peels equally effective and safe for melasma in Indian skin
Kubiak M et al., Evaluation of 70% glycolic peels versus 15% trichloroacetic peels for the treatment of photodamaged facial skin in aging women, Dermatologic Surgery 2014;40(8):883-891 — both peels improved photodamaged skin; glycolic acid showed faster hydration recovery
CIR Final Report on the Safety Assessment of Glycolic Acid and Lactic Acid, their salts and simple esters (Andersen FA), International Journal of Toxicology 1998;17(Suppl 1):1-241
Stiller MJ et al., Topical 8% glycolic acid and 8% L-lactic acid creams for the treatment of photodamaged skin. A double-blind vehicle-controlled clinical trial, Archives of Dermatology 1996;132(6):631-636 — 76% of glycolic acid users improved at least one grade vs 40% vehicle
Garcia A, Fulton JE Jr, The combination of glycolic acid and hydroquinone or kojic acid for the treatment of melasma and related conditions, Dermatologic Surgery 1996;22(5):443-447 — glycolic acid topical products highly effective in reducing melasma pigment
Sources: PubMed · KCI · J-Stage · CNKI · Wanfang · SFD · MFDS · Cochrane · SCCS · CIR. Every entry points to a specific document. See methodology for what each outcome label means.