Phenol

1-TRIMETHYL-2-CYCLOHEXENYL-1-PENTEN-3-ONE

GLYCOLIC ACID

An alpha-hydroxy acid (AHA) that helps to remove the dead skin cells on the surface of the skin reveling a more even, smoother complexation. It is also able to stimulate collagen production with long-term use. Could help to reduce pore congestion. It can be irritating to the skin. Apply sunscreen daily if using products with glycolic acid

LACTIC ACID

An exfoliating and moisturizing alpha-hydroxy acid (AHA). Typically causes less irritation than other AHAs, for example, glycolic acid. At high concentrations (about 15%), lactic acid can help reduce lines and wrinkles. Recent studies show that lactic acid can support the "good" bacteria living on skin's surface (healthy skin microbiom)

RETINOL

Two steps removed from the active form of vitamin A - retinoic acid. Once converted to the retinoic acid in the skin, retinol is proven to be effective against all signs of aging. It improves skin cell turnover, helps fight blemishes and clogged pores, can regulate excess oil production and even skin tone. It can, however, be quite irritating

RETINYL PALMITATE

Three steps removed from the active form of vitamin A - retinoic acid. To have an effect in the skin, it first needs to be converted twice to become the retinoic acid. This means it is less potent than retinol, but could also be less irritating. Once converted to the retinoic acid in the skin, it helps against all signs of aging, improves skin cell turnover and helps fight blemishes and clogged pores. However, in many cosmetic formulations, it is used in a concentration that is too low to have the full effect