This is a question I see over and over in natural forums.
I think the answer is: It depends.
On what? You ask..
1. What Products You Use
I am quite careful about what products I use on my hair. I read labels before I buy and, if there is an ingredient I am not sure of, I google it right there in the shop. (What did we do before Google? Or Mobile Phones? Or Internet??)
Many a shop assistant have looked at me in confusion as I spend ages browsing a small selection of products, phone in hand. Occasionally, one comes up to ask if I need assistance and my response may be 'PEG-120 Methyl Glucose Dioleate; Friend or Foe?' They usually back away slowly. I Kid, I Kid! But you get the gist. Actually I found one of the assistants at the Healthy U in junction quite knowledgeable on Sulfates!