AHA vs BHA vs PHA: Which Exfoliant Is Right for Your Skin
Chemical exfoliation demystified.
Ask ChokChok AI
Get instant answers about "AHA vs BHA vs PHA: Which Exfoliant Is Right for Your Skin"
Try asking
Chemical Exfoliation 101
Chemical exfoliants dissolve the bonds between dead skin cells, accelerating natural turnover without physical scrubbing. They're generally gentler and more effective than physical scrubs, and they're a cornerstone of K-beauty routines. But not all chemical exfoliants are created equal.
AHA: Alpha Hydroxy Acids
What they are: Water-soluble acids derived from natural sources. The most common are glycolic acid (from sugar cane) and lactic acid (from milk).
How they work: AHAs dissolve the intercellular cement on the skin surface, removing dead cells and revealing smoother skin underneath. They work on the skin surface only.
Best for:
- Dullness and rough texture
- Hyperpigmentation and sun damage
- Fine lines and anti-aging
- Dry skin (lactic acid is also a humectant)
Not ideal for: Oily, acne-prone skin with clogged pores (AHAs can't penetrate into pores)
Key consideration: AHAs increase photosensitivity. Always use sunscreen when incorporating AHAs into your routine.
BHA: Beta Hydroxy Acid
What it is: In skincare, BHA almost always means salicylic acid. It's oil-soluble, which is its key differentiator.
How it works: Because BHA is lipophilic (oil-loving), it can penetrate into the sebaceous follicle and exfoliate inside the pore. This makes it uniquely effective for blackheads, whiteheads, and congestion.
Best for:
- Acne and breakouts
- Blackheads and clogged pores
- Oily skin
- Inflammatory skin conditions
Not ideal for: Very dry skin (BHA can be drying)
Bonus: Salicylic acid also has anti-inflammatory properties, making it doubly effective for acne (which involves both clogging and inflammation).
PHA: Polyhydroxy Acids
What they are: Larger-molecule acids like gluconolactone and lactobionic acid. Think of them as AHAs' gentler cousin.
How they work: PHAs exfoliate similarly to AHAs but with larger molecular sizes, which means slower, more gradual penetration. This results in effective exfoliation with significantly less irritation.
Best for:
- Sensitive skin that can't tolerate AHA or BHA
- Rosacea-prone skin
- Beginners to chemical exfoliation
- Eczema-prone skin
Bonus: PHAs are also humectants and have antioxidant properties.
How to Choose
The right exfoliant depends entirely on your skin type and primary concern — not on what's trending.
- Oily, acne-prone: Start with BHA (salicylic acid, 0.5-2%)
- Dull, textured, aging: Go with AHA (glycolic acid 5-10% or lactic acid 5-10%)
- Sensitive, reactive: Try PHA (gluconolactone 3-5%)
- Combination with multiple concerns: Consider alternating AHA and BHA on different days
Usage Rules
- Start with 2-3 times per week, not daily
- Never layer AHA + BHA + retinol in the same routine
- Always use sunscreen during the day (especially with AHAs)
- If your skin becomes red, dry, or stings — scale back frequency
- More is not better. Consistent, moderate use beats aggressive treatment every time
Keep Reading
The Korean toner pad explosion: how Anua, Numbuzin, and Torriden built a category from nothing
The Korean toner pad — a pre-soaked cellulose or non-woven pad in a stack, ready to swipe across the face — was a niche format three years ago. Today it's the defining K-beauty category of the post-2022 era. Anua's Heartleaf 77 Clear Pad started it. Numbuzin No.5 Vitamin Pad ran with it. Torriden, Mediheal, Medicube, and Goodal built parallel platforms. Here's why the format works, who built it, and the definitive buying guide.
Large Pores: What Actually Works (and What's Just Marketing)
A no-nonsense guide to minimizing the appearance of large pores with K-beauty. Which ingredients have real evidence, which products deliver, and why most 'pore-shrinking' claims are nonsense.