Why Does Cutting Onions Make You Cry? | The Science Behind Onion Tears

[00:00:00]Ever wondered why onions make you cry even when you're not sad?

[00:00:03]When you cut an onion, you break its cells. This releases chemicals that react together and create a gas called syn-propanethial-S-oxide.

[00:00:12]The gas rises into the air and reaches your eyes. Your eyes detect it as an irritant and immediately start producing tears to wash it away. That's why chilling an onion in the fridge before cutting it can help it slows down the chemical reaction and releases less gas.