I am only 20 years old but I still worry about the effects the environment has on my hair. I want my hair to look good and be healthy for a very long time. I take pride in my appearance and the way my hair looks and feels is very important to me. I know the chemicals usd in coloring sometimes have an adverse effect on hair, but I love the way my hair looks when it has highlights. So I have it colored at a beauty salon about every three or four months. I also use a blow dryer and staighten it, which makes my hair a little dry and unmanageable. I have used Herbal Essence Shampoos for years (thanks...