Dr. Will Bulsiewicz (gastroenterologist, nutritionist, New York Times-bestselling author of Fiber Fueled and The Fiber Fueled Cookbook) stops by to break down gut health and practical steps we can take to heal our guts. He unpacks gluten, food sensitivities, and fiber’s role in gut health. He explains the significance of microbiomes, challenges highly restrictive diets, and discusses why bowel movements directly inform gut health. Mayim and Dr. B consider the gut’s effect on mood, why digestive issues can still manifest even with proper nutrition, and the evidence-based benefits of a plant-based diet. They discuss the ways food intolerances can lead to disordered eating and how to fix those intolerances, the mental health impact of dietary challenges, and empowering oneself with information about one’s specific dietary needs.