Where Food Goes
When you eat a sandwich, your body has to break it into tiny pieces before it can use it. This job is called digestion. It takes many hours, from the first bite to the end of the trip.
Digestion begins in the mouth. Your teeth chew food into small bits, and saliva makes it wet and starts to break it down. When you swallow, the food goes down a tube called the esophagus. Muscles squeeze it along, which is why you can swallow even when you are upside down.
The food drops into the stomach. Strong muscles churn it, and stomach juices, which contain acid, break it into a thick liquid.
Next, the liquid moves into the small intestine, a long, coiled tube. Here the body takes in nutrients, the useful parts of food. The nutrients pass through the walls of the intestine into the blood, and the blood carries them to every part of the body.
What the body cannot use moves into the large intestine. It takes back water, and the rest leaves the body as waste.