This book is one of the better health related books I've read in a long time. In it, the author lays out a pretty well-reasoned model that we as modern humans have forgotten how to breathe properly. This failure leads to a number of problems including some surprising ones like crooked teeth, weak jaws, and snoring.
I've implemented a number of recommendations from the book (mouth taping!) and have seen some pretty convincing results. I highly recommend reading it for yourself!
