Teeth are strong and amazing tools that help you every day. They help you bite into food, chew, talk to your friends, and of course... smile! It’s important to keep your teeth healthy, and that means brushing them every morning and every night.

Squeaks and I do that, too! You need to brush because otherwise some of the things in your food and drink can hurt your teeth. One of the things that can hurt your teeth is called acid.

Acids are ingredients that taste kind of sour, and they’re in lots of foods and drinks — like oranges, sugary juices, coffee, and soda pop. They might taste good, but because there’s acid in these foods and drinks, they can eat away at your teeth and make tiny little cracks on their surface — so small that you can’t even see them. Then, the color from foods and drinks can get into the cracks, which can make your teeth look yellow or brown.

But brushing cleans away the acid, which helps keep your teeth strong. It also cleans out some of the color from the surface of your teeth, which keeps them nice and white. Do you want to see for yourself how brushing keeps your teeth clean?

Alright! Let’s do an experiment! Are you ready, Squeaks?

[Squeaks squeaks]

For this experiment, we’re not going to test our own teeth, because we want to keep them strong and healthy, so instead we’re going to use... eggs!

And this experiment is going to focus on the very outside of an egg, the eggshell. Eggshells aren’t exactly the same as your teeth, but teeth and eggs are a lot alike because they’re both made up of something called calcium. Calcium is what gives teeth their strength and hardness, so you can bite into things and chew easily.

Since both teeth and eggshells have calcium in them, the acid in soda, fruit juice, and coffee can eat away at an eggshell just like it eats away at a tooth. And then, just like with a tooth, the color in foods and drinks can get into the tiny cracks in the eggshell. You already know that brushing your teeth keeps them clean and healthy, so do you think brushing an eggshell would keep it clean, too?

[Squeaks reacts]

I think so too Squeaks!

Let’s find out! For this experiment, you’ll need a hard-boiled white egg, some soda, a cup, a toothbrush, toothpaste, and help from a grown up. Also, this experiment will take time, so give yourself a day to finish it!

Before you start, grab a grown up to help you hard-boil the egg. Then, put the hard-boiled egg in the cup. Next, fill the cup with soda until it covers the egg.

And now just let the egg sit for a day! We started our experiment yesterday so we have an egg that has been sitting in the soda bath for a day, and now it’s brown! Let’s put some toothpaste on our toothbrush and brush the egg to see what happens! Wow!

Take a look at that! The egg looks much less brown now! So what happened?

The acid in the soda ate away at the eggshell just like it eats away at teeth. Then, the soda’s brown color got into the cracks and stained the egg. But just like with teeth, the toothpaste and toothbrush worked to clean the eggshell.

[Squeaks reacts]

That’s true, Squeaks — the toothbrush didn’t get all of the brown color out.

That’s because the egg was sitting in soda for a whole day, so the stain was a lot worse than what happens when you just drink soda every once in awhile. If you brush your teeth every day, you’ll clean away the acid and color before your teeth start to look like this eggshell.

You can also help keep acid from hurting your teeth by drinking healthier options, like water — or milk, which is chock full of the calcium that makes your teeth stronger! But no matter what you drink, it’s important to brush your teeth and clean away any acids and leftovers from the food you eat.

Thanks for joining us for this egg brushing experiment, and we’d also like to give a big thank you to Google Making Science for helping us make this episode! How did your experiment turn out?

Did you try it with juice or coffee? We’d love to see how it went! If you want to share your experiment with us, just grab a grown up to leave a comment down below, or send us an e-mail to kids@scishow.com. And we’ll see you next time, here at the fort!