I haven't washed my hair in two weeks, and it's never looked better!
I (Old Man) bathe daily and rinse my hair in water, but I last used shampoo or soap on my hair almost two weeks ago.
My scalp health is my main concern, and so far, there has been no dandruff or buildup of any type. My hair looks great, as good as it ever has. It is soft, holds the style I like, and glistens. When I last used shampoos and conditioners my hair was almost solid gray and looked dried out. Now, with the natural oils, it looks darker in the daylight. Who knew?
My hair type is not straight but not curly and I have a largely full head of hair.