The difference between AHA and BHA exfoliants

Paula's Choice AHA and BHA exfoliants for different skin concerns.

Our skin naturally exfoliates dead cells every day, but over time – primarily as a result of age and unprotected sun exposure – this shedding process slows and may stop altogether. The result is dull, dry or flaky skin, clogged & enlarged pores, bumps, wrinkles, loss of firmness and an uneven skin tone.

Without question, a leave-on AHA (alpha hydroxy acid) or BHA (beta hydroxy acid) chemical exfoliant can make a world of difference by removing this build-up of dead skin cells. AHA & BHA exfoliation works to reveal your healthier complexion hiding just beneath the surface.

How are AHA & BHA similar?

AHA and BHA are both good for the skin because they exfoliate in a non-abrasive manner by “ungluing” the bonds that hold dull, dead skin on the surface. Once those bonds are broken – gently and evenly – the skin naturally sheds these dead cells.

What can AHA and BHA do for your skin?

  • Diminish the look of lines and wrinkles
  • Make the skin look and feel firmer
  • Hydrate the skin
  • Improve the look of dull, uneven skin tone
  • Smooth rough, bumpy texture

AHA and BHA products

2% BHA Liquid Exfoliant

Our iconic BHA exfoliant

Our #1 bestseller worldwide, this gentle leave-on exfoliant works beneath the skin's surface to quickly unclog pores, smooth wrinkles, brighten & even out skin tone.

Our breakthrough AHA exfoliant

Resurface texture & tone with this unique blend of mandelic and lactic acid that works gently above the skin’s surface to improve radiance, fine lines & the skin barrier.

Skin Perfecting 6% Mandelic + 2% Lactic Acid AHA Liquid Exfoliant

Why are AHA and BHA different?

AHAs are water soluble, which means they exfoliate on the surface level of the skin. They're generally preferred for normal to dry, sun-damaged skin due to AHA's ability to enhance natural moisturising factors within the skin. They also have been proven effective in reducing visible signs of sun damage, including crepe-y skin and wrinkles.

BHA is oil soluble, so it not only works on the skin’s surface but also deep inside the pores. BHA is therefore the preferred option for normal to oily skin that's prone to bumps, clogs, breakouts and enlarged pores. BHA also has natural skin-calming properties, which makes it gentle enough for sensitive skin or anyone who's prone to redness, rosacea or milia.

Can you use AHA and BHA together?

Yes, you can use both kinds of chemical exfoliation together. Though most people do just fine by picking one or the other, there’s nothing wrong with using both or experimenting to see which one works best for you. Just be sure to monitor how your skin responds and adjust usage if needed.

Using AHA and BHA together can provide advanced results if you’re experiencing multiple skin concerns (such as signs of sun damage, deep wrinkles, stubborn clogged pores or bumps and dull flakiness at the same time). In fact, many people find that alternating AHA and BHA exfoliants is the perfect solution to address their unique concerns.

How can you use both AHA and BHA in your skincare routine?

You can use both AHA and BHA in your routine by alternating their application (e.g. using AHA one day, BHA the next) or by selecting a formula that gently blends them together. Should you apply an AHA and BHA exfoliant at the same time twice a day? Probably not. Most people don’t need that level of exfoliation.

Apply your AHA/BHA exfoliant after your cleanser and toner. You don't need to wait before moving on to your next product, so feel free to immediately follow with the rest of your routine (this won’t throw off the pH of the exfoliant).

Here are our tips on how to alternate exfoliants and how often to exfoliate:

  • Most people do fine exfoliating once daily, morning or evening based on personal preference.
  • If you want to trial alternating AHA & BHA, simply decide which exfoliant to use at the beginning of each week and then switch back and forth day by day. You can also use one for a week, then switch to the other the next week.
  • Another option is to apply one type of exfoliant in the morning and the other at night. This can be a great approach for breakout-prone skin showing signs of sun damage.
  • You also can experiment by alternating different strengths of an AHA or BHA. For example, apply a 1% BHA exfoliant each morning and step up to 2% at night. You can even experiment with using products that combine different AHAs, like our 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant.
  • Once or twice a week, bring a higher-strength specialty AHA or BHA treatment into your routine to give yourself an “at-home peel” experience that delivers dramatic results.
  • For daytime use, always finish with a broad-spectrum SPF 30 or higher.

Remember, it’s all about experimentation to find out what is best for you. Once you know what works for your skin, stay consistent with it to maintain the results.

Can AHA and BHA damage skin?

AHA and BHA exfoliants do not damage the skin when well-formulated and used properly. In fact, AHAs strengthen the skin by supporting healthy collagen, while BHA delivers soothing properties to calm agitated skin.

To work effectively, AHA and BHA exfoliants must be formulated within a narrow pH range: 3-4. We are aware of the research around this issue, so all of our AHA and BHA products are formulated to be as effective and as gentle as possible. It also helps that we never use ingredients that research has proven irritating to the skin.

References for this information:

  • Cosmetic Dermatology: Products and Procedures, Second Edition, 2016, pages 346-356
  • Clinical, Cosmetic, and Investigational Dermatology, August 2015, pages 455-461
  • Dermatology Research and Practice, February 2015, ePublication
  • Journal of the German Society of Dermatology, July 2012, pages 488-491
  • Evidence Based Complementary and Alternative Medicine, June 2011, ePublication
  • Clinical, Cosmetic, and Investigational Dermatology, November 2010, pages 135-142
  • Journal of the American Academy of Dermatology, April 2007, pages 651-663
All skin types
Normal skin, Dry skin
Normal skin, Dry skin
Normal skin, Combination skin

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