The Colon Code: Fiber, Butyrate, and the Microbiome

Your colon is not just a waste pipe.In episode 5 of our Organ Series, Dr. Jace and Dr. Addy explore the colon, fiber, short-chain fatty acids, butyrate, microbiome diversity, constipation, diarrhea, stool transit time, resistant starch, prebiotic foods, and the role your colon plays in immune function and whole-body health.The colon contains roughly 38 trillion bacteria, close to the number of human cells in the body. That means your microbiome is a major part of your biology — and what you feed it matters.This episode breaks down how the colon ferments fiber into short-chain fatty acids like butyrate, propionate, and acetate. Butyrate is the star of the episode because it acts as a major fuel source for colon cells and plays a role in immune signaling, gut barrier health, and communication with the brain.Dr. Jace and Dr. Addy also discuss why most Americans are under-consuming fiber, why diversity matters, how the 30-plant rule can support microbiome health, how hydration impacts stool movement, why squatting mechanics matter, and how transit time can reveal whether things are moving too quickly or too slowly.They also cover red meat, processed meat, carnivore diets, colon cancer risk, fecal microbiota transplant, stool testing, and when colon symptoms should be evaluated by a provider.In this episode, we cover:The colon as a fermentation chamberThe 38 trillion bacteria living in the colonFiber and microbiome diversityShort-chain fatty acids: butyrate, propionate, and acetateWhy butyrate matters for colon healthSoluble fiber, insoluble fiber, resistant starch, and prebioticsThe 30-plant ruleCooked and cooled rice, potatoes, legumes, and green bananasHydration and fiber intakeConstipation, diarrhea, and transit timeThe beet or sesame seed transit testSquatting mechanics and pelvic floor functionWhy suppressing the urge can create problemsPsyllium husk and stool consistencyDysbiosis and stool testingFecal microbiota transplantC. diff, ulcerative colitis, and microbiome restorationProcessed meat vs. unprocessed red meatCarnivore diets and microbiome diversityColon cancer screening and red flagsKey takeaway:The colon is where fiber becomes fuel.A healthy colon depends on rhythm, hydration, movement, plant diversity, resistant starch, prebiotic foods, and a microbiome that is fed well enough to produce beneficial compounds like butyrate.The goal is not just better bowel movements. The goal is better microbiome function, better immune signaling, better gut barrier support, and better long-term colon health.Follow The Functional Code:Instagram: https://www.instagram.com/thefunctionalcodeYouTube: https://www.youtube.com/@TheFunctionalCodeSpotify: https://open.spotify.com/show/3aY5zkhwg5Rzk2q33cbIlfApple Podcasts: https://podcasts.apple.com/us/podcast/the-functional-code-podcast/id1754585557Disclaimer: This podcast is for informational purposes only and is not intended as medical advice. Always consult a qualified healthcare provider.