AHA vs. BHA: what's the difference in skincare?

Pipette with falling drop of oil

The list of ingredients found in any given skincare product can be downright confusing, which is why we are transparent with what goes into all of our products here at REN. We’re here to help you navigate the long lists of ingredients on the back of your bottles so you know not only what you’re using, but why.

Today’s topic is AHA vs BHA. It may sound like a lot of letters, but this class will focus more on science than english. AHA and BHA are acronyms for alpha hydroxy acid and beta hydroxy acid. They are some of the most popular ingredients used in skincare, and for good reason—they come with a host of benefits. But what are they, what’s the difference between the two, and which one is right for your particular skin type?

Don’t worry we’ll get to answering all these questions...

What is AHA?

AHA is short for Alpha Hydroxy Acid. AHAs are water-soluble acid compounds that are often derived from plants and foods such as sugar cane, citrus fruits, apples, and milk.

The most common AHAs found in skincare are glycolic acid and lactic acid. Other AHAs you may come across on an ingredient label include malic acid, citric acid, and mandelic acid. All of these types function as exfoliating acids—that is, they remove dead skin cells from the skin’s surface—but work a bit differently and vary in potency. For example, glycolic acid will be more potent than lactic acid, which will be more gentle.

What is BHA?

BHA is short for Beta Hydroxy Acid. BHAs are oil-soluble acid compounds, so they can easily be absorbed into more oily skin types. One of the most popular BHAs is salicylic acid, which is great at releasing clogged pores and fighting blemishes because it can solubilize in oil and has soothing properties.


Let’s compare and contrast these two acid families…

How They’re Alike

Both AHAs and BHAs are chemical exfoliants that work to dissolve dead skin cells on the skin’s surface. This means you don’t have to physically slough off the skin with an abrasive sponge or beady mask. Why do you want to get rid of dead skin cells in the first place? Well, the benefits of chemical exfoliation are many including a brighter, more even complexion, clear pores, reduced signs of aging, and better penetration of skincare products, to name a few.

How They’re Different

You probably noticed that AHAs are water-soluble and BHAs are oil-soluble. This difference impacts how they are often used in skin care products. Because AHAs are water-soluble exfoliating acids, they are actually hydrating to the skin in addition to being exfoliating, which makes them great for sensitive and dry skin types. BHAs, on the other hand, are primarily used to treat blemishes and visible sun damage, and absorb oil, making them great for oily, blemish-prone skin.

Which One Should You Use?

In the battle of BHA vs. AHA, it’s a draw; each acid wins certain rounds. So, which one you should use depends on your skin concerns and goals. The question of “how often should you exfoliate?” also depends on your skin’s level of sensitivity and needs.

If you want to target blemishes, opt for BHA-containing products. If this is your goal, you’ll love using ClearCalm Clarifying Clay Cleanser which contains Willow Bark Extract, a natural form of salicin from which salicylic acid is derived, to balance oil levels and remove the build-up of dead skin cells.

If you want to target an even skin tone, opt for AHA-containing products. If this is your goal, reach for our Glycolic Lactic Radiance Mask. With a blend of Glycolic, Lactic, and Citric acid, it’s packed with AHAs to help smooth skin texture, even skin tone, and help firm and restore a glow to skin.

If you are looking for smoother skin all over, try a lactic-acid containing body product such as our AHA Smart Renewal Body Serum, which will gently exfoliate skin and leave it not only smooth, but with a natural glow too.

You Can Have Both

Yes, you read that right—you don’t have to put these two acids up against one another. You can use both an AHA exfoliant and BHA exfoliant as long as you use them in gentler formulas that your skin type can handle. Some of the best and gentlest exfoliation products, in particular, contain both AHAs and BHAs, namely our cult-favorite AHA Skincare Tonic. Don’t let the name fool you. It features the BHA, Salicin, in addition to the AHA, lactic acid, to help dissolve in-pore build up and help skin appear smoother. With face exfoliator products such as this, you can get brighter and healthier-looking skin—no acid left out.


About the Author

Camille Poggi is a doctor in Pharmacy (PharmD.) and is passionate about skincare and how the skin works in general. She specializes in the cosmetic industry and worked for renowned companies in France like L’Oréal and Chanel before moving to London. After being a training manager for 4 years, Camille is at ease with explaining how products work in the skin and how to adapt her speech according to the audience.

She joined REN in January 2020 as International Training Manager and moved to the Research & Development team earlier this year to be the new Scientific Education Manager. A tailored-made role where she assesses and leads all technical communication and ensures scientific compliance is always met. She’s also involved in new product development from the earliest stages. Finding a way to create sustainable skincare products and making sure the message is properly delivered and understood is definitely a big challenge but also her favourite part working for REN.



  1. Meaning of Exfoliating
  2. How Often Should I exfoliate my face
  3. Salycic Acid
  4. Comparative Effectiveness of AHAs