Alpha hydroxy acid is water soluble and beta hydroxy acid is oil soluble. This means beta hydroxy acid is better on oily skin with whiteheads and blackheads. Alpha hydroxy acid is better on thickened, sun-damaged skin.
Chemical peels usually contain between 10-20% alpha hydroxy acid. Doctors can use peels with up to 70% alpha hydroxyl acid. This treatment will last from 2-5 years.