Routines

How to Exfoliate Your Skin: Chemical vs Physical Exfoliation Guide

Learn how to exfoliate your face safely with AHAs, BHAs, and physical methods. Includes frequency, product picks, over-exfoliation signs, and expert tips.

How to Exfoliate Your Skin: Chemical vs Physical Exfoliation Guide

A 2021 review in the Journal of Clinical and Aesthetic Dermatology found that regular chemical exfoliation with alpha hydroxy acids improved skin texture, reduced hyperpigmentation, and increased epidermal thickness by up to 25% over 12 weeks. Exfoliation is one of the most impactful steps you can add to a skincare routine — but only when done correctly. Too little and you miss the benefits; too much and you wreck your skin barrier.

Quick Summary:

  • Chemical exfoliants (AHAs and BHAs) are safer and more effective than physical scrubs for most skin types
  • AHAs like glycolic acid work on the skin's surface and are best for dullness, fine lines, and sun damage
  • BHAs like salicylic acid penetrate pores and are best for acne, blackheads, and oily skin
  • Most people should exfoliate 2-3 times per week, not daily
  • Over-exfoliation is the most common mistake — redness, stinging, and increased breakouts are warning signs to stop

What Is Exfoliation?

Your skin naturally sheds dead cells roughly every 28 days. As you age, this cycle slows — by your 40s, it can take 45-60 days. When dead cells pile up, skin looks dull, pores appear larger, and products absorb poorly.

Exfoliation speeds up removal through physical tools (scrubs, brushes) or chemical agents (acids, enzymes). The American Academy of Dermatology recommends exfoliation as part of a healthy routine but cautions that method and frequency must match your skin type.

Chemical vs Physical Exfoliation

This is the single most important decision in your exfoliation routine, and dermatologists overwhelmingly recommend chemical exfoliants for most people.

Physical Exfoliation

Physical exfoliants use abrasive particles or tools to buff away dead cells. The problem is control — it's easy to apply too much pressure, create microtears, and trigger inflammation. A 2013 study in the Journal of Dermatological Science showed aggressive physical exfoliation increases transepidermal water loss, weakening the skin barrier.

Gentle physical exfoliation (soft washcloth, finely-milled scrub) once or twice a week is fine for non-sensitive skin. Avoid harsh walnut shell scrubs and stiff brushes.

Chemical Exfoliation

Chemical exfoliants use acids or enzymes to dissolve the "cement" (desmosomes) holding dead cells together. They work evenly without friction risks, and you control intensity through concentration and contact time — not hand pressure. They fall into two categories: AHAs and BHAs.

Chemical exfoliant on cotton pad

AHAs: Alpha Hydroxy Acids

AHAs are water-soluble acids that exfoliate the skin's surface by dissolving bonds between dead cells in the stratum corneum. The two most common AHAs are glycolic acid and lactic acid.

Glycolic acid has the smallest molecular size, so it penetrates most effectively. A 1996 study in Dermatologic Surgery found that 8% glycolic acid applied over 22 weeks significantly improved fine wrinkles, rough texture, and mottled pigmentation. It's the gold standard AHA for uneven texture and hyperpigmentation.

Lactic acid has a larger molecule, penetrates more slowly, and causes less irritation. Research in the Journal of Cosmetic Dermatology confirmed it increases ceramide production at 5-12%, strengthening the skin barrier while exfoliating — an excellent choice for dry or sensitive skin.

BHAs: Beta Hydroxy Acids

BHAs are oil-soluble, which gives them a completely different superpower — they can penetrate through sebum into the pore lining. Salicylic acid is the primary BHA in skincare, and it's the go-to exfoliant for anyone dealing with clogged pores, blackheads, or acne.

A 2015 review in Clinical, Cosmetic and Investigational Dermatology confirmed that salicylic acid acts as both a keratolytic and comedolytic agent, dissolving keratin plugs inside pores while providing anti-inflammatory benefits. It's one of the few over-the-counter ingredients approved by the FDA for acne treatment.

Best for: acne, blackheads, whiteheads, oily skin, enlarged pores

Enzyme powder wash in jar

AHA vs BHA: How to Choose

The choice between AHA and BHA comes down to your primary skin concern:

Concern Best Choice Why
Acne and blackheads BHA Oil-soluble, penetrates pores
Dullness and texture AHA Surface exfoliation reveals brighter skin
Fine lines and wrinkles AHA Stimulates collagen production
Oily skin BHA Regulates sebum, clears pores
Hyperpigmentation AHA Accelerates pigmented cell turnover
Sensitive skin Lactic acid (AHA) Gentle, barrier-supporting
Dry skin Lactic acid (AHA) Hydrating properties

If you have combination skin, you can alternate — BHA on oily areas and AHA on dry or dull areas, or use them on different nights.

Verdict: For most people, a chemical exfoliant used 2-3 times per week delivers better, safer results than any physical scrub. Choose BHA if your main concern is acne or oily skin, AHA if you're targeting texture, tone, or aging. Start with a low concentration and increase gradually.

How to Exfoliate: Step by Step

For Chemical Exfoliants (Liquid/Toner Format)

  1. Cleanse your face and pat dry. Chemical exfoliants work best on clean, dry skin.
  2. Apply your exfoliant with a cotton pad or your fingertips, avoiding the eye area and any broken skin.
  3. Wait 1-2 minutes for absorption before moving to the next step.
  4. Follow with a hydrating serum or moisturizer. Exfoliated skin absorbs hydration better, so this is the perfect time for hyaluronic acid.
  5. Apply sunscreen the following morning — all exfoliants increase sun sensitivity for up to a week after use.

Frequency Guide

  • Beginners: Once per week for the first 2 weeks
  • Building tolerance: Twice per week for weeks 3-4
  • Established routine: 2-3 times per week (this is the sweet spot for most people)
  • Experienced users with tolerant skin: Up to daily for mild formulations only

Never exfoliate on the same night you use retinol. These are both active ingredients that increase cell turnover, and combining them in the same routine dramatically increases irritation risk.

Best Exfoliating Products

For Acne and Oily Skin (BHA)

Paula's Choice 2% BHA Liquid Exfoliant (around $32) is the benchmark BHA product — a leave-on liquid at 2% salicylic acid with a pH of 3.2, right in the effective range. It clears blackheads, smooths texture, and reduces breakouts with consistent use. For a budget option, CeraVe SA Cleanser (around $16) combines salicylic acid with ceramides in a gentle rinse-off format.

For Dullness and Texture (AHA)

The Ordinary Glycolic Acid 7% Toning Solution (around $9) delivers effective AHA exfoliation at an unbeatable price. Use it 2-3 evenings per week after cleansing. COSRX AHA 7 Whitehead Power Liquid (around $22) uses glycolic acid at 7% in a gentle base that works well for sensitive skin while still brightening and smoothing.

For Overnight Exfoliation

Good Molecules Overnight Exfoliating Treatment (around $8) combines a blend of AHAs for a gentle, overnight resurfacing effect. Apply it after cleansing on your exfoliation nights and wake up to noticeably smoother skin.

Signs of Over-Exfoliation

Over-exfoliation damages your moisture barrier — the lipid layer that keeps water in and irritants out. The damage is often worse than not exfoliating at all. Watch for these warning signs:

  • Persistent redness that doesn't fade within an hour of cleansing
  • Stinging or burning when you apply products that normally feel fine (especially moisturizer)
  • Increased breakouts — a damaged barrier triggers inflammation and bacterial issues
  • Unusual dryness or flaking despite regular moisturizing
  • Shiny, tight-feeling skin that looks almost waxy
  • Increased sensitivity to sun, wind, and temperature changes

If you notice these symptoms, stop all exfoliation immediately. Switch to a bare-minimum routine — gentle cleanser, ceramide-rich moisturizer, and sunscreen — for at least 2 weeks. A 2018 study in the International Journal of Cosmetic Science found that barrier recovery takes 2-4 weeks with proper care.

Common Exfoliation Mistakes

Exfoliating every day. Your skin needs time to regenerate between sessions. Daily acid use strips the barrier faster than it can rebuild. Two to three times per week is enough.

Combining multiple exfoliants. A glycolic toner plus a BHA serum plus an exfoliating scrub is a recipe for barrier damage. Pick one chemical exfoliant and stick with it.

Layering exfoliants with retinol. Both increase cell turnover, but combining them in one session causes compounded irritation. Alternate nights instead.

Scrubbing too hard. With physical exfoliants, let the product do the work. Light, circular motions are all you need.

Ignoring sun protection. Freshly exfoliated skin burns faster and is more prone to hyperpigmentation. Sunscreen is non-negotiable.

Frequently Asked Questions

How often should I exfoliate my face?

Two to three times per week works for most skin types. Beginners should start once per week and increase gradually. If your skin stings when you apply moisturizer or looks red after exfoliating, you're overdoing it.

Can I exfoliate if I have acne?

Yes — and you should. BHA exfoliation with salicylic acid is one of the most effective treatments for acne because it clears the pore clogs that cause breakouts. Avoid harsh physical scrubs on active acne, though, as they can rupture inflamed pimples and spread bacteria.

Is chemical or physical exfoliation better?

Chemical exfoliation is safer and more effective for most people. It works evenly without friction, and you control intensity through concentration rather than pressure. Gentle physical exfoliation (soft washcloth, enzyme scrub) is fine but carries higher irritation risk.

What happens if I over-exfoliate?

You damage your moisture barrier, leading to redness, stinging, increased breakouts, and heightened sensitivity. Recovery takes 2-4 weeks of a minimal routine with no active ingredients.

Can I exfoliate with retinol in my routine?

Yes, but not at the same time. Use your exfoliant on certain nights and retinol on others. Applying both together stacks two cell-turnover treatments and commonly causes excessive dryness and peeling.

Should I exfoliate in the morning or at night?

Evening is better. Applying acids at night gives your skin hours to recover before sun exposure. If you exfoliate in the morning, sunscreen afterward is essential.

Do I need to exfoliate my body too?

Body skin benefits from exfoliation, especially areas prone to ingrown hairs, keratosis pilaris (those small bumps on upper arms), or body acne. A BHA body wash or an AHA body lotion used 2-3 times per week handles this effectively.

What's the difference between AHA and BHA?

AHAs are water-soluble and work on the skin's surface — best for dullness, fine lines, and pigmentation. BHAs are oil-soluble and penetrate into pores — best for acne and oily skin. See our glycolic acid and salicylic acid guides for details.

Can I exfoliate sensitive skin?

Yes, with the right product. Lactic acid at 5% is the gentlest chemical exfoliant for sensitive skin. Start once per week and monitor closely. Avoid high-concentration glycolic acid and all physical scrubs if your skin is reactive.

Will exfoliation help with dark spots?

AHA exfoliation accelerates turnover of pigmented cells, gradually fading dark spots. Glycolic acid is the most studied AHA for this purpose. Consistent use over 8-12 weeks with daily sunscreen produces the best results for hyperpigmentation.

Is there anyone who shouldn't exfoliate?

People with active eczema, severe rosacea, sunburned skin, or open wounds should skip exfoliation until those conditions resolve. If you're on prescription retinoids, your skin already has accelerated turnover — adding an exfoliant requires your dermatologist's guidance.

The Bottom Line

Exfoliation clears dead skin, brightens your complexion, and helps every other product in your routine absorb better. Choose a chemical exfoliant — BHA for acne and oily skin, AHA for texture and tone — and use it 2-3 times per week. Start slow, protect your barrier, and wear sunscreen. That's it.

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