Imagine for a moment that your favorite food is a super special toy. One day, someone tells you that you can't play with that toy anymore because it could hurt your tummy. This is what happens to some people with gluten. Gluten is a special ingredient that is found in some foods that can hurt some people's tummies.
Gluten is like the glue that helps hold things together. It's found in foods like bread, pasta, and even some soups and sauces. Some people have something called celiac disease, and that means gluten can really hurt their tummy. Their body gets confused and thinks gluten is a bad guy trying to hurt them, so it fights against it.
To help their tummies feel better, people with celiac disease have to eat a "gluten-free diet." This means they don't eat things with gluten in them. It might sound tricky, but there are lots of yummy foods they can still eat like fruits, veggies, meats, and even special gluten-free pasta and bread.
So, just like some toys are not meant for some kids, gluten is not meant for some people. And just like how we want to keep our tummies healthy, people with celiac disease want to eat foods that won't hurt their tummies.