In The Symbiont Factor (http://amzn.to/1jz3kPt), I explain that one of the most important variables that we can influence to improve our gut bacteria is autonomic tone. When we are stressed, we become sympathetic (think “fight or flight”) dominant and this functional pattern inhibits digestion and gut mobility. This inhibition is also very harmful to beneficial gut bacteria! So, what can be done short-term to reverse this pattern? Breathing exercises. When under stress, most people suppress their breathing, contributing to sympathetic autonomic tone. When you take deep breaths instead, it stimulates your parasympathetic system, and this is the system that makes your gut function improve. Gut bacteria thrive in this functional pattern! Now the only question is how to learn to improve breathing dynamics and build a “better-breathing” habit. One resource that I found tremendously helpful in learning this came from one of the sports I participate in: Freediving. There is a great book called Breatheology, written by Stig Severinsen, which deals with specifically that: how to improve our breathing. You can find the book here: http://amzn.to/1nQYwAr. FYI-as I’m in Arkansas, I earn nothing from that link/referral; I’m listing it purely because I think it is that good! Of course, it makes a nice complement to the book I wrote…