No poo is a movement of people who are foregoing washing their hair with shampoo. There is even a book out on the subject, 'Happy Hair, the No Poo Book'. I tried to go no poo for one month and while my hair actually looked nice, my scalp wasn't very happy. For me and my family, the next best thing to no poo (in terms of low waste living) is a bar of shampoo! I wash my hair about once a week and it looks lovely :)
By using a shampoo bar, you use less plastic (making plastic involves a process of using the earths resources, so using less is a good thing). And when you use less plastic, you discard less plastic. Also a good thing.
You also put less chemicals into your own body, and our water systems when you use a milder shampoo bar (ever read the ingredients on the back of your bottle?) Less chemicals in our water means less endocrine disruptors in our water, which is important for the health of our children and the environment. There are multiple stories to learn more, including one on NPR about the state of the Potomac (DC's main source of drinking water).
Here is a little bit of history on shampoo: In India several hundred years ago people used essential oils to freshen their hair. Then in the US about one hundred years ago shampoo was created- the kind where you lather up your hair and rinse it out clean. When you shampoo your hair you are taking away the natural oils on the base of your hair shaft. Your head wants those oils to be there because it protects your hair and scalp, so the more you shampoo, the more your head will produce oils. Its a supply and demand issue.
The next time your bottle of shampoo runs out, consider buying a bar of shampoo. You might just surprise yourself at how much you like it!
I'd love to hear back from you about the state of your hair :)