But Why – A show for curious kids
Why do onions make you cry?
1/2/2026 | 2m 4sVideo has Closed Captions
Why do onions make you cry? Asks Sophie from Italy.
Something takes over when you cut into an onion... first you feel fine, but then you can get the sudden sensation to start CRYING! What's the deal?!
Problems playing video? | Closed Captioning Feedback
Problems playing video? | Closed Captioning Feedback
But Why – A show for curious kids is a local public television program presented by Vermont Public
But Why – A show for curious kids
Why do onions make you cry?
1/2/2026 | 2m 4sVideo has Closed Captions
Something takes over when you cut into an onion... first you feel fine, but then you can get the sudden sensation to start CRYING! What's the deal?!
Problems playing video? | Closed Captioning Feedback
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What's in sugar that makes it sweet? Asks Olive from Australia. (2m 47s)
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Providing Support for PBS.org
Learn Moreabout PBS online sponsorshipOnions.
They're what I like to call powerhouse produce there in lots of recipes and for good reason.
They're aromatic, which means smelly and flavor rich, with lots of ways to cook and eat them.
But onions have a dark side even when you don't feel sad, they can make you cry.
Why do onions make you cry?
Now onions make you cry, but not because you're sad or happy.
Well, I guess unless you really love onions when you cut into one, your eyes can get really irritated and tear up.
Believe me, it is not a pleasant sensation.
Onions grow underground and naturally absorb sulfur when you cut into one that's sulfur gets smushed into enzymes in the other layers of the onion as they're pushed together by the knife, and they create an irritating chemical called syn-Propanethial-S-oxide.
Oh, that's a mouthful.
Kind of like an onion.
Once that chemical hits the air, it starts to spread and drift.
If it gets in your eyes, it can produce sulfuric acid.
Yikes.
Luckily, your body naturally responds by producing tears to wash it all away.
Not all onions are the same.
Some sweeter varieties don't contain as many of those chemicals as other more strongly flavored versions.
And people have come up with lots of funny tricks to avoid tearing up, like wearing goggles or running water.
But here's another eas one pop an onion in the fridge or freezer about ten minutes before chopping it.
The cold will slow any chemical reactions that occur once you start slicing, so you have a little time before the tears set in.
That's just one solution, but it is a safe and easy way to avoid the irritation.
Though wearing goggles sounds much cooler.
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