Salicylic Acid is a beta hydroxy acid (BHA). It’s an exfoliating acid that has smoothing, brightening, and regenerating qualities alongside its star talent of working deep into pores to unclog them. Salicylic acid is the optimal ingredient for tackling blackheads and whiteheads. It gently dissolves oily skin debris while providing anti-inflammatory benefits to help acne spots shrink and disappear more quickly.
Salicylic acid, being a “keratolytic agent,” benefits all skin types by normalizing the shedding of skin cells for a smoother overall skin texture. Plus, salicylic acid is a mild tyronaise inhibitor, so may help to brighten and balance skin tone.1 Since salicylic acid promotes exfoliation and the shedding of dead cells, it can effectively stimulate skin’s repair process.2
Chemistry wise, the hydroxy part of a BHA molecule is separated from the acid part by two carbon atoms, as opposed to an alpha hydroxy acid (AHA) where they’re separated by one carbon atom. Salicylates are more oil soluble than their water soluble AHA counterparts and can therefore penetrate pores more effectively.
 Chang TS. An updated review of tyrosinase inhibitors. Int J Mol Sci. 2009;10(6):2440–2475. Published 2009 May 26. doi:10.3390/ijms10062440
 Abdel-Motaleb, AA, Abu-Dief, EE, Hussein, MRA. Dermal morphological changes following salicylic acid peeling and microdermabrasion. J Cosmet Dermatol. 2017; 16: e9– e14.