What Are Beta Hydroxy Acids, AKA BHAs?

If you want clear, more even-toned skin, you need to do more than just cleanse your face — you need to exfoliate. As for which type of exfoliant to choose, a formula with beta hydroxy acids — or BHAs, for short — is the best for acne-prone and oily skin types. It's not hard to find skin-care products formulated with this particular group of acids, especially if you're looking for products geared toward pimples, blackheads, and dark spots left over from breakouts.

If you've ever used a product with salicylic acid in it, you've used a beta hydroxy acid before. But that's not to say you know everything there is to know about this powerful category of skin-care acids. To learn more about BHAs — including what they are, how to use them in your routine, and their skin-care benefits — keep reading.

Not to be confused with alpha hydroxy acids (aka AHAs), beta hydroxy acids are exfoliating agents that break down dirt and bacteria deep in pores. "Beta hydroxy acid is another acid commonly used in dermatology and cosmetics," Ife J. Rodney, MD, founding director of Eternal Dermatology + Aesthetics, previously told POPSUGAR. "Unlike AHAs, which are water-soluble, BHAs are oil-soluble, which allows them to penetrate our skin's oil glands to remove debris and dead cells from deep within the pores."

There are many ingredients that are considered a BHA. The most common is salicylic acid, and its popularity is well-earned. Derived from willow bark, salicylic acid has both anti-inflammatory and antibacterial properties and helps promote turnover to exfoliate away dead skin cells on the surface of the skin. This helps treat both active breakouts and discoloration from healed pimples. Other lesser-known examples of beta hydroxy acids are beta hydroxybutanoic acid, tropic acid, and trethocanic acid.

The reason BHAs are so great for oily and acneic skin types is due to their large molecular size, which helps them exfoliate the surface layer of the skin. As stated above, BHAs target a long list of skin-care concerns surrounding acne. The ingredient chemically exfoliates dead skin cells to promote a clearer complexion and reduce the appearance of hyperpigmentation, targets congestion and dirt in pores with its antibacterial properties to prevent future breakouts from occurring, helps reduce inflammation of active pimples, and reduces excessive oil production.

It's not difficult to find products containing salicylic acid — cleansers, serums, spot treatments, and face masks for oily skin are usually packed with the ingredient. Because the ingredient plays well with AHAs in the right doses, you'll often find them combined to up their skin-clearing benefits. Just remember that BHAs can be drying, so it's best to stick to one acne-fighting product at a time in your routine unless otherwise instructed by a dermatologist.