Type of Ingredient: Skin-Soothing, Exfoliant, and Anti-Acne
Main Benefits: Mainly works as an exfoliant, but also acts as an anti-inflammatory, antiseptic, denaturant, anti-dandruff agent, hair conditioning agent, skin-conditioning agent, and preservative.
Who Should Use It: In general, it is used to treat blackheads, whiteheads, and acne-related problems.
Ideal For These Concerns: Hyperpigmentation, acne, dryness, enlarged pores, sun damage, and dark spots.
How Often Can You Use It: It can be used every day, ideally at night to avoid sun exposure.
What Beta-hydroxy acids?
Beta-hydroxy acids are a group of naturally occurring acids that has multiple benefits for many skin problems and concerns. Like alpha-hydroxy acids, beta-hydroxy acids are also naturally derived from plants. They even have some of the main benefits when it comes to skin. The main difference between the two is their solubility. Alpha-hydroxy acids dissolve in water while beta-hydroxy acids dissolve in oil. This is helpful to know as your skin type will influence which type of hydroxy acids will work best.
The benefits of beta-hydroxy acids
When beta-hydroxy acids are added to your favorite skincare products, they can break down dead skin cells and support a healthy exfoliation. In lower concentrations, beta-hydroxy acids can help improve the skin's complexion. In higher concentrations, beta-hydroxy acids can penetrate deeper into the lower layers of the skin which adds additional benefits like supporting collagen and the elastin, the essential proteins in your skin, and helping to improve the health of your skin from within.
Because beta hydroxy acid is oil soluble, it penetrates deeper than your skin’s surface skin and can clean out clogged pores that cause acne. Studies show that BHAs like salicylic acid are more effective and less irritating than AHAs in tackling whiteheads, blackheads, and acne.
Beta hydroxy acid also helps tackle inflammation caused by acne and hyperpigmentation caused by acne or other pigmentation on the skin’s surface. This is also known as post-inflammatory hyperpigmentation or PIH or melasma.
Like AHAs, beta hydroxy acid helps speed up the skin cell renewal at the skin’s surface. This helps remove hyperpigmented skin layers for newer skin layers. AHAs may be more effective in this but beta hydroxy acids also show good results.
Those of you who used to have acne and are now dealing with the outcome know how difficult it is to reduce the post-inflammatory hyperpigmentation to have a truly clean face, without acne and acne scars and pigmentation. So this is great news for people with post-inflammatory hyperpigmentation.
As beta hydroxy acid helps remove the topmost layers of skin, it can also help treat dandruff on the scalp in the same way. Given the antibacterial, anti-inflammatory, and the exfoliating properties of beta hydroxy acids, they can act to soothe itching and reduce dandruff, redness, and flaking.
So salicylic acid can be as effective, if not more, than a zinc pyrithione in reducing dandruff. Zinc pyrithione is certainly more popular in dandruff shampoos today. Many people also find it is very harsh on their hair, but with not knowing of another alternative, continue to use it. Salicylic acid is gentler on the scalp without losing effectiveness and so could be a better option for you if you suffer from dandruff.
The Best Beta Hydroxy Acid: Salicylic Acid
If you’ve ever picked up an acne-fighting product, you’ve heard about salicylic acid. Salicylic acid is a naturally occurring beta-hydroxy acid that is derived from willow bark. Like alpha hydroxy acids, salicylic acid can exfoliate the skin helping to remove dead skin cells. However, as the beta-hydroxy acid on this list, salicylic acid can dissolve in the oil and get deep into pores helping to decongest them and clear breakouts. Salicylic acid is antibacterial as well which is another reason it is a beloved acne-fighting ingredient. Another common benefit of salicylic that isn’t as widely discussed is its ability to combat hyperpigmentation. Salicylic acid is often used by darker-skinned people to neutralize skin discolorations caused by hyperpigmentation. Of course, salicylic acid is best for people with acne-prone skin, but other skin types can appreciate its benefits as well. It can be a bit drying to the skin in higher concentrations, so always follow up with a moisturizer, especially those with dry skin.
The safety of beta-hydroxy acids used as a cosmetic ingredient has been evaluated by both the cosmetic industry and the FDA. At a meeting in February 2000, the Cosmetic Ingredient Review (CIR) Expert Panel, the cosmetic industry's independent body for reviewing the safety of cosmetic ingredients, reached the tentative conclusion that the use of beta-hydroxy related substances in cosmetics is "safe as used when formulated to avoid irritation and when formulated to avoid increased sun sensitivity." CIR added that "when sun sensitivity would be expected, directions for use [should] include the daily use of sun protection.".
1. Handbook of Chemistry and Physics, CRC Press, 58th edition page D150-151 (1977)
2. Dawson, R. M. C. et al., Data for Biochemical Research, Oxford, Clarendon Press, 1959.