In this “Lessons” episode, Dr. Steven Gundry reveals how your gut health may be the single most important factor in determining your lifespan. He explains how the gut, often called the “second brain,” plays a central role in everything from heart disease and dementia to brain fog and inflammation. Drawing from both cutting-edge research and ancient cultures, he shows how most modern diseases begin in the gut due to damaged microbiomes and chronic inflammation—and why restoring that internal ecosystem through diet and lifestyle is key to reversing illness and achieving long-term health.