Salicylic Acid

BHA is an acronym for beta hydroxy acid, which is more commonly known as salicylic acid. Salicylic acid is a desmolytic ingredient, which means it is able to exfoliate by dissolving the bonds that hold the dead cells to skin’s surface. Because salicylic acid is oil soluble, it also has the ability to penetrate into the pore lining and exfoliate inside the pore. This makes it especially effective for reducing breakouts, including blackheads and whiteheads.

Salicylic acid is recognised as an over-the-counter topical acne product by the U.S. FDA, when used in concentrations of 0.5–2%. Even though salicylic acid is best known for its ability to address acne-prone skin concerns, it offers many additional properties that any skin type can benefit from. Case in point, by exfoliating the buildup of dead skin on the surface, it also helps reverse the appearance of dull, uneven skin tone, as well as other visible signs of ageing skin.

Unlike physical exfoliants (such as a rough facial scrub), salicylic acid offers hydrating properties that enhance the result of smooth, soft skin. Another unique advantage is salicylic acid’s ability to gently soothe aggravated skin thanks to its inherent calming properties.

Salicylic acid works most effectively as a leave-on treatment, ideally within a pH range between 3 and 4. Rinse-off salicylic acid cleansers typically have a higher pH, which likely won’t offer much of an exfoliation benefit—not to mention the contact time with skin is very brief—but the salicylic acid may at least offer skin-calming benefits in this form and can be included in amounts as low as 0.5% to achieve this benefit. Research shows using salicylic acid starting at a 1–2% concentration is recommended for regular exfoliation within a skin care routine. For more stubborn concerns, higher concentrations can make a dramatic difference. In dermatologic practices, salicylic acid has been safely used in concentrations as high as 50% for the removal of warts, corns, pigmented lesions, and other advanced concerns. Salicylic acid has been found to be safe on all skin tones and ethnicities.

Note that BHA is the structural name for salicylic acid and is completely unrelated to the preservative ingredient BHA (butylated hydroxyanisole). In short, salicylic acid is a beta hydroxy acid particularly beneficial for oily or acne-prone skin: it exfoliates the skin and refines pore appearance whilst reducing acne formation at appropriate concentrations.