ab 12 • Audiobook • 01:20:01 • September 2026

You know there are trillions of bacteria living in your gut, and you have a vague sense they matter. But every explanation either turns into a diet lecture or drowns you in Latin names, and you still could not say what those microbes actually do all day. Press play and your gut becomes a great river-harbour city. Your mouth is the customs gate, your stomach an acid quarantine dock, your small intestine a roaring trading floor, and your colon a fermenting warehouse district where roughly a hundred trillion residents work, bargain and occasionally riot. Chapter by chapter you follow a meal through the city, meet the microbial families who run it, listen in on the gut-brain phone line, and watch what a course of antibiotics does to the streets. Every chapter ends on a genuine wow, and where science does not yet know, you hear that too. By the last chapter, your own digestion feels like a place you have visited. Press play and walk through the gates.