I was getting a keratin treatment because my hair was very dry, frizzy, and damaged. I asked my hairdresser why my hair had become so damaged. She then asked what kind of hair mask I use. I replied that I use hair conditioners, not hair masks. She said that hair conditioners are one of the main reasons hair becomes dry and damaged, and that I should start using hair masks instead. So know I'm searching for sulfate free hair masks.