The Details of Digestion
Your digestive system converts everything you eat and drink into the fuel you need to function — and survive.
The digestive tract, also known as the gastrointestinal (GI) tract, transports and processes your meals, delivering essentials to your bloodstream and eliminating the rest. Its components include, in sequential order: mouth, esophagus, stomach, small intestine, and large intestine (colon). The system also includes the liver, which produces digestive juices, processes nutrients, and eliminates toxins.
Your GI tract includes about thirty feet of hollow tubes — including your stomach, which holds less than a quarter-cup when empty and more than eight cups after a big buffet, and your small intestine, which contains millions of tiny villi that collectively make your intestinal surface area about 200 times bigger than that of your skin.
First, you chew your food and swallow it, propelling it into your esophagus. It's passed along through a series of involuntary smooth muscle movements into the stomach, where it's churned together with digestive juices and sent into the small intestine. Once there, it's combined with other juices, some from the intestine and others from the liver and pancreas.
In the small intestine, essential nutrients are absorbed into the bloodstream, and what's left — now considered waste — moves into the large intestine, where much of the remaining fluid is removed. It's then sent to the rectum, where it's eliminated.
