Salicylic Acid (BHA)

SPEED DIAL #42

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AHAs (alpha-hydroxy acids) and BHAs (beta-hydroxy acids) are usually pluralized that way, but it’s a bit misleading. While there are many AHAs (ex: glycolic and lactic), there is only one BHA: salicylic acid. The key differentiator is solubility. AHAs are water-soluble, meaning they work on the surface to dissolve bonds between dead cells. BHAs are oil-soluble, so they penetrate into the pore lining and exfoliate from within, hence why salicylic acid is such a popular choice for oily and congested skin. Plural or not, BHA always means salicylic acid (SA).