What Are Beta-Hydroxy Acids (BHAs) and What Do They Do?

What Are Beta-Hydroxy Acids (BHAs) and What Do They Do?

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If you’ve ever dealt with acne or oily skin, you’ve probably stumbled upon BHAs at some point. BHAs, or beta-hydroxy acids, are a class of mild acids commonly used in skincare products, especially those designed to treat acne. These naturally-occurring acids have been used to treat minor complexion concerns for more than 2,000 years. BHAs are effective yet gentle and are often featured in over-the-counter acne treatments, including several of our best-selling cleansers and moisturizers.

But, not everyone knows that BHAs can do a lot more than clear blackheads and banish breakouts. These naturally-derived acids are powerful exfoliants and can help address the appearance of noticeable signs of aging, including dullness. Ahead, we’ll do a deep dive into beta-hydroxy acids and their uses in skincare, plus introduce you to some of our favorite products formulated with these ingredients. Keep reading for what you should know about BHAs.

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First Off: What Are Beta-Hydroxy Acids?

Beta-hydroxy acids are a type of mild acid found in plants, tree bark, fruit, and some dairy products. In skincare formulations, they act as a gentle chemical exfoliant to help brighten the complexion and minimize the occurrence of acne breakouts. Some research confirms BHAs are also effective at smoothing visible fine lines and wrinkles and evening skin tone.I

What Do BHAs Do?

Every day, the average adult sheds around 500 million skin cells. Most of the time, these dead skin cells flake off easily and without us noticing. Sometimes, however—particularly for those with oily complexions — these dead cells cling to the skin’s surface or get stuck in pores. This can cause the complexion to appear dull and may result in the formation of acne blemishes.

Beta-hydroxy acids help remove this debris from the skin’s surface by dissolving the bonds that hold the dead skin cells together. This enables more efficient exfoliation and promotes a clearer, smoother complexion. The exfoliating effect of BHAs can also help to address isolated incidents of hyperpigmentation, like sunspots or post-acne marks over time. Additionally, some research suggests that high concentrations of beta-hydroxy acids, like those in prescription formulas or professional chemical peels, can help stimulate collagen production and improve skin texture and elasticity.II

Types of Beta-Hydroxy Acids

The most common types of BHAs in skincare are salicylic acid and its derivatives. Salicylic acid is a popular ingredient known for its exfoliating properties. Like all BHAs, it helps loosen dead skin cells to enable more efficient exfoliation. This helps promote a brighter, more even-looking skin tone.

Clearly Corrective Dark Spot Solution is formulated with salicylic acid, vitamin C, and peony extract. This solution works to gently exfoliate the skin’s surface and visibly reduce the appearance of dark spots and discolorations. This potent serum is suitable for all skin types, evens tone, and helps promote a brighter, more even complexion. We recommend it for those looking to improve the look of sun spots or post-acne marks or for anyone who wants to add a complexion-brightening boost to their skincare routine.

Beyond helping with tone, salicylic acid is lipid-soluble, which means it can dissolve in oil. This allows salicylic acid to penetrate clogged pores and break up the dirt, sebum, and debris that commonly lead to acne. Research indicates that regular use of salicylic acid can also reduce sebum production, making it an especially useful ingredient for those with oily or blemish-prone complexions.III Though it’s available in many different strengths, it’s typically used in low-concentration over-the-counter acne treatments.

Salicylic acid is an ingredient found in several of our formulas designed for acne-prone skin, including Blue Herbal Acne Cleanser Treatment. This effective foaming cleanser helps remove dirt, oil, and other debris to purify pores and prevent new blemishes from forming. For additional benefits, we recommend pairing it with Breakout Control Acne Treatment Facial Lotion, which also contains salicylic acid, aloe vera, and niacinamide (a.k.a. vitamin B3). Together, these ingredients help diminish breakouts and improve skin tone and texture for a smoother, clearer complexion.

How Should I Use BHAs?

How you use BHAs will depend on a few factors, including your skin type, complexion concerns, and the type of product you’re using. For mild acne and exfoliation, it’s generally best to reach for a formula with a 1-2% concentration, as this is potent enough to be effective but not too harsh on the skin.

Our Blue Herbal Spot Treatment contains an effective yet gentle 1.5% concentration of salicylic acid to help clear active blemishes, like blackheads and whiteheads. We recommend applying a small amount directly to the breakout one to three times per day until it disappears. While BHAs are gentle, irritation may still occur, particularly for those with sensitive skin. As such, it’s best to start slow and adjust your usage based on how your skin reacts.

It’s also important to note that, like most topical acids, BHAs can cause sun sensitivity, making the skin more prone to sunburns and sun damage. We recommend always wearing a broad-spectrum sunscreen if you’re using any type of BHA treatment. Be sure to follow all expert recommendations for safe sun exposure and limit time in the sun as much as possible.

Beta-hydroxy acids aren’t the only type of acid used in skincare. Read our article Acids for Skin to learn the difference between various acids and how to use them on your skin.

I Arif, Tasleem. "Salicylic Acid As a Peeling Agent: A Comprehensive Review." Clinical, Cosmetic, and Investigational Dermatology vol. 8 455-61. 26 Aug. 2015, doi:10.2147/CCID.S84765
II Ganceviciene, Ruta, et al. "Skin Anti-Aging Strategies." Journal of Dermato-Endocrinology, vol.4,3 (2012): 308-19. doi:10.4161/derm.22804 III "Beta Hydroxy." Gale Encyclopedia of Alternative Medicine. 12 Aug. 2020.

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