This. I live in a major city and our water is majorly chlorinated. I read a bit about this online and thought, sure, what the heck, I'll try eliminating chlorinated water and see what happens.

Now I have an under-counter water filter and all our drinking water has a significant amount of the chlorine filtered out. It made a huge difference for me. YMMV, and of course doesn't mean much for well water.

In what world does this comment get down-voted?

This is the basis for an elimination diet, which is key to discovering food sensitivities.

Seriously...