Alpha hydroxy acids, or AHAs, are functional acids derived from natural sources: glycolic acid comes from sugarcane, lactic acid comes from milk, and mandelic acid comes from bitter almonds. All AHAs work by weakening the bonds between dead skin cells on the surface of the skin, allowing them to slough off naturally, revealing smoother, brighter skin underneath.

AHAs are exceptional at smoothing rough skin and bringing out a glow. By exfoliating away dead skin cells, they can help unclog pores and fight blemishes. AHAs can fade hyperpigmentation from sun damage, blemishes, and hormones. They also stimulate collagen production, leading to firmer, smoother skin.

The more popular AHAs like glycolic and lactic acid come with downsides, though. They can cause significant irritation, especially for those with sensitive skin, and overuse can lead to a damaged moisture barrier. In addition, in those with darker skin tones, glycolic acid can actually cause hyperpigmentation, a counterintuitive side effect.

Mandelic acid is a much larger molecule than glycolic or lactic, meaning it doesn’t penetrate the skin as deeply. That means it can still exfoliate on the surface of the skin, but it won’t cause nearly as much irritation.

Mandelic acid is the ideal AHA for those with sensitive skin and those with darker skin tones. It not only smooths and brightens skin, but fights blemishes, increases skin firmness, and unclogs pores.