After repeated use 2 I can not say definitively how much this shampoo affects the health of my hair. You really need only a very small amount of shampoo to the hair to be washed, which is ever a plus! The hair shine generally a little more after the application, but that individual highlights are highlighted by the shampoo more, me so far is not really noticed. (For one star deduction) I have a natural ash blonde hair color and let me always move some bright streaks, but my hair is not quite as fine as perhaps some blonde hair. After the 2nd washing occurred with prior total so that the hair is stronger, which could be an advantage for blondes with very fine hair. The hair looks a little thicker and bulkier total. I have previously made with the toiletries Redken always very good experience and the shampoo'd definitely order again. Just do not expect miracles when it comes to color reflections in blond hair, but by the care her it's 1a!