Sodium laureth sulfate (SLES) and sodium lauryl sulfate (SLS) are two ingredients that can be found in nearly every commerical shampoo. They are defined as detergents and surfactants.
Recent studies about the effect of SLS in particular have raised concern about this chemical and the harm it is doing to the hair and skin. It irritates the scalp and causes rashes and allergic reactions. It causes thinning hair.
But because of the foaming action of these chemicals, the shampoo makers consider it a vital ingredient in the shampoo. The foaming action, or suds, makes people think a product such as a soap or shampoo is cleaning the hands or the hair because of the suds. But this is not the case. The suds are just for show!
If your hair is thinning, or if regular shampoos seem to irritate your scalp, try a shampoo from a health food store that does not have SLES or SLS in it.
You can also use household products to wash your hair like baking soda. Yes, baking soda. Those who use it say it works great. Mix with enough water to make a paste and use just like shampoo. You might want to rinse with a little vinegar to get all the baking soda out. Just pour about a tablespoon into a glass and use as a rinse.