As a stylist I have been told to tell my clients to use "sulfate-free" shampoo if they have color-treated(or curly) hair. However, I read in your book that you've studied the performance of sulfate-free vs shampoos containing sulfates and didn't see a difference in hair color fading. Is there anything out there that preserves freshly colored hair?! Is there any benefit of using a sulfate-free shampoo as far as frizz goes?! I stumbled upon this company, purely perfect
, and that say sulfates damage the hair?!