Why do onions make us cry, and how can we prevent it?

Onions make us cry because they release tiny chemical messengers when we cut them.

When you slice an onion, you break its cells apart. Inside each cell are little sacks full of a strong-smelling chemical called sulfur compounds. When the cells are broken, these sacks burst open and release their contents into the air.

The sulfur compounds then react with the water in your eyes, making a new kind of liquid, like a tiny, invisible tear factory right inside your eye! This liquid makes you feel like crying because it irritates your eyes.

There are fun ways to stop the tears from happening. One way is to cover your eyes with a bowl while cutting the onion. That traps the chemical messengers and keeps them from reaching your eyes.

Another way is to cut the onion under running water, which washes away some of the chemicals before they can reach your eyes.

You can also try chewing gum, it makes you breathe through your mouth, so the chemicals don’t go into your nose and eyes as much.

Just like when you get a paper cut and it stings, cutting onions is like getting a little chemical pinch in your eye, but with tears!