Exfoliation is one of the most transformative steps in skincare — but also one of the most misunderstood. Too much and you damage your barrier. Too little and you deal with dullness, congestion, and uneven texture. This guide breaks down the four major exfoliating acid families: AHA, BHA, LHA, and PHA, what they do, who they’re for, and how to use them safely.

What Exfoliation Actually Does

Exfoliation removes dead skin cells from the surface or from inside the pores. Depending on the acid, it can:

• Brighten dull skin
• Smooth texture
• Reduce breakouts
• Fade pigmentation
• Prevent ingrown hairs
• Improve hydration
• Strengthen the skin barrier

The key is choosing the right acid for your skin type — and using it consistently, not aggressively.

The Four Types of Exfoliating Acids

Best for: Dry, dull, textured, or sun‑damaged skin
How it works: AHAs are water‑soluble and exfoliate the surface of the skin. They dissolve the bonds between dead skin cells, revealing smoother, brighter skin.

Benefits:

• Brightens dull skin
• Smooths fine lines
• Helps fade pigmentation
• Improves overall radiance

Best for: Oily, acne‑prone, congested skin
How it works: BHAs are oil‑soluble, meaning they travel deep into pores to dissolve oil, debris, and dead skin. This makes them ideal for blackheads, breakouts, and ingrown hairs.

Benefits:

• Clears clogged pores
• Reduces blackheads
• Calms inflammation
• Prevents ingrown hairs

LHA — Lipohydroxy Acid

Best for: Sensitive or reactive skin that still needs pore‑level exfoliation
How it works: LHA is a gentler, slow‑release derivative of salicylic acid. It penetrates gradually, offering controlled exfoliation with less irritation.

Benefits:

• Very gentle pore exfoliation
• Helps with breakouts
• Suitable for sensitive skin
• Supports smoother texture

PHA — Polyhydroxy Acids

Best for: Sensitive, rosacea‑prone, or barrier‑compromised skin
How it works: PHAs have larger molecules, so they stay on the surface and exfoliate very gently. They also attract moisture, making them ideal for hydration‑focused routines.

Benefits:

• Gentle exfoliation
• Hydrating
• Strengthens the skin barrier
• Great for redness‑prone skin

Acid Type	Best For	How It Works	Strength
AHA	Dry, dull, textured skin	Surface exfoliation	Strongest surface action
BHA	Oily, acne‑prone, ingrown hairs	Deep pore exfoliation	Strongest pore action
LHA	Sensitive + acne‑prone	Slow‑release pore exfoliation	Gentle BHA alternative
PHA	Sensitive, reactive skin	Gentle surface exfoliation + hydration	Gentlest overall

How to Choose the Right Acid

Choose AHA if you want:

• Glow
• Smoother texture
• Help with pigmentation
• Anti‑ageing benefits

Choose BHA if you want:

• Clearer pores
• Fewer blackheads
• Less oiliness
• Ingrown hair prevention

Choose LHA if you want:

• BHA‑like results with less irritation
• A slow‑release, gentle exfoliant

Choose PHA if you want:

• The gentlest exfoliation possible
• Hydration + exfoliation in one
• Barrier‑friendly resurfacing

How Often Should You Exfoliate?

• AHA: 1–3 times per week
• BHA: 2–4 times per week (or daily if tolerated)
• LHA: Daily or every other day
• PHA: Daily (very gentle)