Richard Nikoley of Free the Animal (a blog about paleolithic diet and exercise) writes that he has been showering without soap or shampoo for the past six months. Here are some of his observations:
Took about two weeks to normalize. That is, I felt my hair was greasy and skin oily up to then.
My skin & hair have never been softer. Never.
If anything, my hair is less "greasy" than ever, yet shampoo hasn't touched it in over six months.
Private parts. Have to address this, of course. This is the biggest benefit of all. Surprised? You'll just have to try it, because I'm not going to elaborate. That's why they call them "private parts." OK, a clue: maybe it's the constant cleansing that's the cause of the sweaty-stinky problem in the first place? If for nothing else, I'm soap free for life on this point alone. I feel as though I've been scammed -- and liberated. I can't explain further. You'll just have to try.
The commenters on his blog share similar soap-free experiences.
Paleo I Don’t Care: I Like No Soap; No Shampoo.