Your hair is dead protein cells. All shampoo does is clean of dirt, sweat and oil. The skin of the scalp is like the rest of your body -keeping it clean and free of a build up of dirt, sweat, body oil and dead skin cells allows it function well and keep the body healthy. Sweat and body oils contain urea, ammonia, and other waste chemicals. urea and Ammonia are used in dyes and chemical treatments that damage the hair so a build up of oil and sweat isn't doing your hair or scalp any favors. Shampoos are needed to clean away dirt and oil from the scalp. The problem for the hair is that some shampoos roughen up the outer layer of the hair strand. That's easily remedied with a conditioner. Conditioners make the scaly outer layer of the hair lay flat so it no longer looks rough. Some conditioners add other ingredients to repel water so the strands don't get frizzy in the rain. Some add stuff that coats the hair strand and adds shine. some act like glue and stick split ends back together. They all have on thing in common, they wash away every time you wash your hair. So use a gentle shampoo when needed and be sure you wash the scalp, use a bit of conditioner on the strands, never brush wet hair, only use a comb, and remember: Hair is not alive -it;'s just dead protein cells sprouting from your head.