In the last episode, Dr. Martin discussed how our bodies have the ability to regenerate. Over the course of a year, we essentially get a new body.  An astute listener followed up with Dr. Martin, asking why we end up dying if our bodies regenerate. The answer is that our blood is tainted. It breaks down and oxidizes and eventually rusts us out. Dr. Martin uses the example of a speed governor on a truck to explain why we ultimately have a shelf life. Dr. Martin also discusses studies on the microbiome. Researchers are finally making the connection that disease really does start in the gut.