How to Start Using AHA and BHA Exfoliants
Chemical exfoliants such as AHAs (like glycolic and lactic acid) and BHAs (like salicylic acid) help loosen dead surface cells. Used gently they can smooth skin texture, but overuse is a common cause of irritation.
Know the Difference
AHAs are water-soluble and work mainly on the skin's surface, often chosen for texture and dullness. BHAs are oil-soluble and can penetrate into oil-filled pores, which is why salicylic acid is often used for oily or breakout-prone skin. You generally do not need both at once when starting out.
Start Slowly
Begin with a lower concentration once or twice a week and increase frequency only as your skin tolerates it. Apply to clean, dry skin, usually at night, and follow with moisturizer. Avoid combining acids with retinoids on the same night when you are new to either, to limit irritation.
Avoid Over-Exfoliation
More is not better. Signs of over-exfoliation include redness, stinging, tightness, and a compromised barrier. If you see these, pause exfoliating and focus on hydration and barrier repair. Acids can increase sun sensitivity, so daily sunscreen is important. Patch-test any new acid first.
- AHAs are water-soluble and work on the surface; BHAs are oil-soluble and reach into pores
- Start with a low strength once or twice a week
- Avoid pairing acids with retinoids the same night when new
- Over-exfoliation causes redness and stinging; pause if it appears
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What is the difference between AHA and BHA?
AHAs like glycolic and lactic acid are water-soluble and work on the skin's surface to brighten and smooth, while BHA like salicylic acid is oil-soluble and gets into pores. In Korean skincare both are used sparingly, a few times weekly, always with daily sun protection.
What is BHA and what does it do?
BHA, usually salicylic acid, is an oil-soluble exfoliant that can penetrate pores to dissolve oil and dead skin, helping refine the look of texture and blemish-prone skin. In Korean routines it's used a few times weekly, with sunscreen by day, to avoid over-exfoliating.
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General educational information using cosmetic structure-function wording — not medical advice. Always patch-test new actives. © KoreaPlus.