Chemical Exfoliation Guide: AHA vs BHA Explained (Best Products for Every Skin Type)

If you've ever looked at ingredient lists on exfoliating products and felt completely confused by AHA, BHA, glycolic acid, salicylic acid, and all those other complicated terms, you're not alone.

Chemical exfoliation is one of the most powerful tools in your skincare arsenal—but it can also be intimidating. Use it wrong, and you risk irritation, redness, or even damaged skin. Use it right, and you'll unlock smoother, brighter, more radiant skin than you ever thought possible.

In this complete guide, you'll learn everything you need to know about chemical exfoliation: what it is, how it works, AHA vs BHA differences, how to start safely, and the best products for your skin type.

What Is Chemical Exfoliation? (And Why It's Better Than Scrubs)

Chemical exfoliation uses acids or enzymes to dissolve the bonds between dead skin cells, allowing them to shed naturally. Unlike physical exfoliants (scrubs, brushes), chemical exfoliants work under the skin surface for deeper, more effective results.

Why Chemical Beats Physical:

• ✅ More gentle and controlled
• ✅ Penetrates deeper for better results
• ✅ No risk of microtears (unlike harsh scrubs)
• ✅ Works on multiple skin layers simultaneously
• ✅ Addresses texture, tone, acne, and aging all at once
• ✅ Can be customized to your skin's needs

The science: Chemical exfoliants break down the "glue" (desmosomes) that holds dead skin cells together, allowing fresh, healthy cells to surface faster.

The Two Main Types: AHA vs BHA

This is where most people get confused. Let's break it down simply:

AHAs (Alpha Hydroxy Acids) - Water-Soluble

What they are: Water-loving acids derived from fruits, milk, or sugar

Where they work: Skin SURFACE (epidermis)

Best for:

• Dry, dull skin
• Sun damage and dark spots
• Fine lines and wrinkles
• Uneven texture
• Normal to dry skin types

Common AHAs:

• Glycolic Acid: Smallest molecule, most powerful, penetrates deepest
• Lactic Acid: Gentler, hydrating, great for sensitive skin
• Mandelic Acid: Largest molecule, most gentle, good for beginners
• Citric Acid: Brightening, antioxidant properties

BHAs (Beta Hydroxy Acids) - Oil-Soluble

What they are: Oil-loving acids that can penetrate through sebum

Where they work: INSIDE pores (dermis)

Best for:

• Oily, acne-prone skin
• Blackheads and whiteheads
• Clogged pores
• Redness and inflammation
• Combination to oily skin types

The main BHA:

• Salicylic Acid: The only true BHA used in skincare, anti-inflammatory, unclogs pores

AHA vs BHA: Quick Comparison Table

Feature	AHA	BHA
Solubility	Water-soluble	Oil-soluble
Where it works	Skin surface	Inside pores
Best for	Dry, dull, aging skin	Oily, acne-prone skin
Main benefit	Brightening, anti-aging	Unclogging pores, acne
Sun sensitivity	High (increases photosensitivity)	Moderate
Irritation risk	Higher (especially glycolic)	Lower (anti-inflammatory)

How to Start Chemical Exfoliation (The Safe Way)

This is CRITICAL: Chemical exfoliants are powerful. Start slow to avoid damaging your skin barrier.

Beginner's Protocol (Weeks 1-4):

Week 1-2: Use ONCE per week

• Choose: Low concentration (5-8% AHA or 0.5-1% BHA)
• Apply at night only
• Follow with moisturizer
• Wear SPF 30+ next day (non-negotiable!)

Week 3-4: Increase to TWICE per week

• Space applications 3-4 days apart
• Monitor for irritation, redness, or sensitivity
• If any signs appear, drop back to once weekly

Month 2+: Gradually increase to 3-4x per week (if tolerated)

• Listen to your skin
• Never exceed your skin's tolerance
• Consider skin cycling for optimal results

The Golden Rules:

• ✅ ALWAYS patch test new products (48 hours)
• ✅ NEVER use multiple exfoliants at once (at first)
• ✅ ALWAYS wear SPF 30+ during the day
• ✅ NEVER exfoliate on irritated or broken skin
• ✅ ALWAYS hydrate and moisturize after exfoliating

Best Chemical Exfoliants by Skin Type

🌵 For Dry, Dull Skin: AHAs

1. The Ordinary Lactic Acid 10% + HA
Price: ~$7
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• Gentle AHA perfect for beginners
• Hydrating formula won't dry skin
• Great for sensitive skin
• Start 2x per week

2. COSRX AHA 7 Whitehead Power Liquid
Price: ~$16
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• 7% glycolic acid (moderate strength)
• K-beauty favorite for texture
• Targets closed comedones
• Lightweight, fast-absorbing

3. Paula's Choice 8% AHA Gel Exfoliant
Price: ~$32
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• 8% glycolic acid for visible results
• Gel texture absorbs quickly
• Anti-aging benefits
• Great for normal to oily skin too

💧 For Oily, Acne-Prone Skin: BHAs

4. Paula's Choice 2% BHA Liquid Exfoliant
Price: ~$32
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• The gold standard BHA product
• 2% salicylic acid (perfect strength)
• Unclogs pores dramatically
• Reduces blackheads within 1-2 weeks

5. COSRX BHA Blackhead Power Liquid
Price: ~$18
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• 4% natural BHA (betaine salicylate)
• Gentler than pure salicylic acid
• Great for sensitive oily skin
• Korean skincare cult favorite

6. The Inkey List Beta Hydroxy Acid
Price: ~$12
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• 2% salicylic acid serum
• Budget-friendly option
• Clean, simple formula
• Perfect for daily use

🌸 For Sensitive Skin: Gentle Options

7. The Ordinary Mandelic Acid 10% + HA
Price: ~$7
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• Largest AHA molecule = gentlest
• Great for rosacea-prone skin
• Still effective but super gentle
• Less irritation risk

8. Naturium Lactic Acid Emulsion 5%
Price: ~$18
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• Low concentration for beginners
• Creamy, hydrating formula
• Won't sting or burn
• Great starting point

⚡ For Advanced Users: Stronger Options

9. The Ordinary AHA 30% + BHA 2% Peeling Solution
Price: ~$7
View on Amazon

• ⚠️ STRONG: Only for experienced users
• Weekly treatment (max 10 minutes)
• Dramatic resurfacing results
• Not for beginners or sensitive skin

10. Drunk Elephant T.L.C. Framboos Glycolic Night Serum
Price: ~$90
View on Amazon

• 12% AHA + BHA blend
• Luxury treatment
• Anti-aging powerhouse
• Visible results in 1-2 weeks

How to Layer Chemical Exfoliants with Other Products

This is where most people make mistakes. Here's the RIGHT way:

✅ Safe Combinations:

Exfoliant + Niacinamide: GREAT combo! Wait 10 minutes after exfoliating, then apply niacinamide. Reduces irritation and boosts results.

Exfoliant + Hyaluronic Acid: PERFECT! Apply HA serum after exfoliant to replenish hydration.

Exfoliant + Moisturizer: ESSENTIAL! Always moisturize after exfoliating to prevent dryness and irritation.

❌ Dangerous Combinations (Avoid!):

AHA/BHA + Retinol: TOO MUCH! Can cause severe irritation. Use on alternate nights or try skin cycling.

AHA + BHA Together: Generally too harsh for most people. Start separately, combine later if needed.

Exfoliant + Vitamin C: Can work BUT risky for beginners. Both lower pH = potential irritation. Use vitamin C in AM, exfoliant in PM.

The Perfect Exfoliation Routine

🌙 Night Routine (Exfoliation Night):

1. Cleanse: Double cleanse for clean canvas
2. Dry completely: Wait 5 minutes (exfoliants work best on dry skin)
3. Apply exfoliant: Thin layer all over face (avoid eyes)
4. Wait 10 minutes: Let it work
5. Hydrate: Apply hyaluronic acid serum
6. Moisturize: Use rich night cream
7. Optional: Slugging for extra barrier protection

☀️ Morning After (CRITICAL):

1. Gentle cleanser: No harsh cleansing
2. Hydrating toner: Replenish moisture
3. Antioxidant serum: Vitamin C or niacinamide
4. Moisturizer: Light day cream
5. SPF 50+: NON-NEGOTIABLE! Exfoliants increase sun sensitivity

When Will You See Results?

Here's the realistic timeline:

• 1-2 weeks: Smoother texture, less rough patches
• 3-4 weeks: Brighter complexion, fading dark spots
• 6-8 weeks: Reduced acne, clearer pores, fewer breakouts
• 12+ weeks: Improved fine lines, overall skin transformation

Important: Consistency is key! Weekly use gives better results than occasional strong treatments.

Signs You're Over-Exfoliating (Stop Immediately If You See These!)

• ❌ Persistent redness or burning
• ❌ Increased sensitivity to all products
• ❌ Shiny, tight, "glass-like" skin
• ❌ Peeling or flaking (beyond initial adjustment)
• ❌ Increased breakouts (compromised barrier)
• ❌ Stinging when applying moisturizer

The fix: Stop all exfoliants immediately. Focus on barrier repair with gentle cleansers, ceramides, and occlusive moisturizers for 2-4 weeks.

Chemical Exfoliation for Specific Concerns

For Acne:

Use BHA (salicylic acid) 2-3x per week. Focus on acne-prone areas. Avoid over-drying—hydration is still important!

For Dark Spots/Hyperpigmentation:

Use AHA (glycolic or lactic acid) + vitamin C in AM. Be patient—pigmentation takes 8-12 weeks minimum.

For Anti-Aging:

Alternate nights: AHA one night, retinol the next. This gives maximum anti-aging without over-irritation.

For Texture (Rough, Bumpy Skin):

Start with mandelic acid (gentle), then progress to glycolic acid (stronger) as tolerance builds.

Professional Treatments vs. At-Home: What's Worth It?

At-Home Exfoliants:

Concentration: 2-30% (depending on acid)
Cost: $7-90 per product
Results: Gradual, cumulative over weeks
Best for: Maintenance, consistent improvement

Professional Peels:

Concentration: 30-70%
Cost: $150-500 per session
Results: Dramatic, visible after 1 session
Best for: Severe concerns, special occasions

My recommendation: Start with at-home products. They're safer, more affordable, and effective for most people. Save professional treatments for stubborn issues or special events.

Your Personalized Exfoliation Plan

Not sure which exfoliant to choose? Use our AI Skin Analysis tool to get personalized recommendations based on your specific skin type, concerns, and goals.

Get your custom routine in under 60 seconds—including which acids to use, how often, and what concentration to start with!