What is the primary action of alpha hydroxy acids on the skin?

Alpha hydroxy acids (AHAs) are primarily known for their ability to exfoliate the stratum corneum, which is the outermost layer of the skin. This exfoliation occurs because AHAs help to break down the bonds that hold dead skin cells together, making it easier for those cells to slough off. As a result, the skin appears smoother and more radiant after AHA treatment.

While AHAs can have hydrating effects and may contribute to skin brightening and the smoothing of fine lines as secondary benefits, their primary function is indeed exfoliation. The removal of dead skin cells promotes cellular turnover, leading to fresher skin underneath. This process can also help to improve skin texture and tone, which are important for achieving overall skin health. Thus, the emphasis on exfoliation accurately reflects the main action of alpha hydroxy acids on the skin.