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.
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- First, with the help of saliva, you chew up your food into a swallowable mass. This is called a bolus. In your stomach, the food will be broken up into a mushy liquid. That liquid then slides into the small intestine. That’s where the body can access and absorb most of the nutrients in food.
- Poop starts to form in the large intestine. Poop is all the stuff your body can’t use. The intestines also pull much of the remaining liquid out of the poop. Then, your body will release it.
- Liquid waste, pee, is handled by the kidneys and the bladder. They are separate systems.
- Poop is brown mainly because of substances known as bile and bilirubin. These yellow-green and yellow substances kind of dye your poop, turning it brown. The food you eat can also affect the color.
- Poop smells bad because of bacteria in your intestines that are producing gas as they break down the food. Certain foods also contain chemicals that have distinct and strong smells when they break down.
- Poop contains trillions of germs! Bacteria are actually the main ingredient in poop. Those bacteria are living in your gut and keeping you healthy, so there’s nothing to worry about when they’re where they should be. But you shouldn’t touch poop because if the bacteria gets in your mouth, you could get sick.
- We have to poop because if we didn’t we’d explode! Think of your intestines like a stretchy tube. There’s a limit to how much they can hold. You have to empty the trash in your system regularly to make room for more.
- Farts are just gas that builds up in the digestion process. They stink for the same reasons that poop does - it’s the gas created by bacteria as they break down your food.
