Alpha Hydroxy Acids (AHA)

Updated June 11, 2009.

Alpha hydroxy acids (AHAs) are naturally occurring molecules found in fruit and milk. They have been used for centuries to soften and exfoliate the skin. Alpha hydroxy acids, along with their close counterparts beta hydroxy acids, work by loosening the bonds that hold dead cells together, allowing them to slough away more effectively.

The AHAs most commonly found in skin care products include:

  • glycolic acid
  • lactic acid
  • tartaric acid
  • salicylic acid (beta hydroxy acid)

Alpha hydroxy acid products are available both over-the-counter and by prescription, depending on the strength used. They are common ingredients in many skin care products, especially anti-aging and anti-acne treatments. AHAs also can be used as the exfoliating agent for chemical peels.

The use of alpha hydroxy acids may help improve acne, as well as soften the look of fine lines and wrinkles, and even out skin tone and texture.