Count me in with the people who can't stand to go even one day without shampooing my hair! I guess I must have an oily scalp. Which shouldn't be surprising, considering how much my forehead shines in all my photos.
Well, it is true that, as I age, and in the winter especially, I can go a *little* further between shampoos - maybe two days, sometimes three if I push it - and as long as i re-wet/restyle, and my last shampoo was a double sudser (Critical!!!). And after any hair coloring, to ensure the color sticks, I do often go three days, even if it's dreadful to do so.
I have been told by stylists that you "just have to get over the initial stages" - that your hair and scalp will eventually adjust. But it just doesn't work. I have really, honestly given it my best shot here!!!! I just feel gross, my hair looks awful, eventually oil starts dripping into my scalp, I itch, etc.
I did try dry shampoo awhile back - I still have the sample, in fact. It sucked. My hair ended up looking like it was one of those powdered white wigs!! LOL. And I didn't use much at all. And worse: my scalp itched like the dickens....
My girlfriend can go an entire week without shampooing her long, thick hair. I have no idea how she does it, but she looks great even on day 7.