# Why Chewing Matters

A classroom teaching model shows how a bite travels from the teeth down the food pipe into the stomach, and why chewing well makes the trip easier

By Yenner Schmeidler

Topic: Human Body & Medicine

[Open the interactive Jig](https://ask.jig.com/j/N7EVQWes35g8)

## Transcript

### 1. Where does a bite go?

Every bite you eat goes on a journey through a long tube inside your body\. This model shows the first part: the mouth, the food pipe and the stomach\. Let's find out why chewing well makes the whole trip easier\.

From mouth to the very end, the whole digestive tube is about 8 to 9 metres long\.

### 2. Teeth cut and grind

Digestion starts in your mouth\. Front teeth cut, and the wide back teeth, called molars, grind\. Chewing breaks one big chunk into lots of tiny pieces\.

Tiny pieces have much more surface, so digestive juices can reach more of the food at once\.

### 3. Saliva makes it slippery

While you chew, saliva \(spit\) soaks the food\. It makes the pieces soft and slippery and starts breaking down starch\. Your tongue presses everything into a soft ball called a bolus\.

Saliva contains amylase, an enzyme that begins turning starch into sugar\.

### 4. Down the food pipe

When you swallow, a little flap covers your windpipe and the bolus enters the esophagus, your food pipe\. Rings of muscle squeeze behind the food and push it down\. A soft, well\-chewed bolus reaches the stomach in about 5 to 10 seconds\.

This squeezing wave is called peristalsis\. It even works upside down\!

### 5. The stomach churns

The stomach is a stretchy bag of muscle\. It squeezes and churns food with strong acid until it becomes a thick soup called chyme\. Only tiny bits, about 1 to 2 millimetres, can pass the gate into the small intestine\.

Food usually stays in the stomach for about 2 to 4 hours\.

### 6. Chewed or gulped?

Now compare\. A big, barely chewed lump stretches the food pipe and moves slowly, so it can feel stuck on the way down\. Gulping fast also swallows extra air\. Switch between the two and watch the tube\.

### 7. A stuffed, bubbly stomach

Big lumps take the stomach longer to break down, and eating fast makes it easy to overfill\. Swallowed air comes back as burps or a bloated tummy\. A very full stomach can push acid back up the food pipe, a burning feeling called heartburn\.

### 8. Chew like a champion

Take small bites, chew until the food is soft and mushy, and slow down\. Your teeth do the hard work so your food pipe and stomach don't have to\. Small bites also help prevent choking, especially for little kids\.

There is no magic number of chews: just keep going until it feels soft\.