Why do we have to poop? Why does fiber make you poop? Why is poop brown? Why does it smell so bad? Why do farts smell bad, too? Yup, we’re going there! In this episode, Mary Roach, author of Gulp: Adventures on the Alimentary Canal, answers your questions about those things that we’re told not to talk about in polite company: poop and farts. We learn how astronauts use the bathroom in space and how many germs are in one ounce of poop.