I really like this podcast. He also appears regularly on many other ones. I'd never heard of the physiological changes that go along with mouth breathing. I am primarily a nose breather except for when I sleep on my back (so my wife tells me). Thirty years of meditation have taught me to be hyper aware of my breathing. Have you heard of Dr. Berg on YouTube? He has a lot of helpful content.
RE: Breathing In And Out - A Diary Of A Mouth Breather