Why does cutting onions make you cry?
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Snow White will have you on your feet. I think that's a wonderful idea. And cheering for more. I was thinking the same thing. Experience the magical story. Magic mirror on the wall. Who's the fairest one of all? Snow White. Disney's Snow White. Only in theaters Friday. Rated PG. Parental guidance suggested. Tickets on sale now. Hi, friends. Did you catch our little experiment, Moment of Calm?

It was a week of soothing science and chill sounds, plus a sleepy time dragon story. We'd love to hear your thoughts. Did it help you sleep better or help calm you down? Maybe you didn't notice the difference. Let us know by going to brainson.org slash contact. Thanks. Again, share your thoughts about Moment of Calm at brainson.org slash contact. From the brains behind Brains On, this is the Moment of Um.

Answering those questions that make you go, um. Moment of Um comes to you from APM Studios. I'm Nervous Nelly. I'm hosting a big dinner party tonight for all my friends with food, games, and unstructured chit-chat.

I don't know why I ever agreed to do this. There are so many things to worry about. Like, what if all my friends arrive at the same time, but the front door gets jammed and I can't let them in and then everyone decides to leave? Or what if I get really tooty from eating too many cheese cubes and I try to blame it on the dog, but then someone says, she who smelt it dealt it and everyone laughs.

Or what if I'm chopping a bunch of onions and they make my eyes tear up so much that I can't see and then I bonk straight into a wall? That would be a disaster. Why does chopping onions make your eyes water anyway? My friends Samuel and Noah had the same question. Let's ask someone who knows a lot about onions.

The reason they make you cry is because it's actually a defense mechanism from the plant. I am Kenji Lopez-Alt and I am a cookbook author and a children's book author. This is a plant's way of saying, "Hey, like stay away from me. I don't want you to eat me." The actual chemicals that cause us to cry, they're called lacrimators. Lacrimose, it's a big word, but it means sad. Something that makes you cry is lacrimose. So these lacrimators are chemical compounds, sulfur-based chemical compounds that irritate our eyes and make us cry.

The interesting thing about onions and garlic and other things that create these sort of sharp chemicals is that those lacrimators don't actually exist in the onion when it's growing in the ground or when it's sitting on the supermarket shelf. You can bring a whole onion right up to your eye and it's not going to make you cry. Those chemical compounds are actually created after we cut the onion open. The number of these lacrimators are created depending on how you slice the onion. So if you use a real dull knife that's going to crush a lot of onion cells,

you're going to create a lot more lacrimators than if you use a real sharp knife, which is going to cleanly slice through the cells and not rupture quite as many of them. So because of this also, there's also different ways we can deal with protecting our eyes while we're cutting onions. The absolute best way to protect your eyes is to wear swim goggles because that's going to completely block any of these chemical compounds from coming in touch with your eye. Aside from that, you know, the best things to do are to keep your knife really sharp,

and to make sure that, well, you're working with someone who can handle a sharp knife, to work quickly. Also keeping your onions chilled can help a little bit because that will slow down the chemical reactions. If you're going to serve raw onions, it can definitely help to soak them in water. There's a couple ways that soaking onions in water can affect them. One is that it is going to draw out some of those lacrimato, some of those chemical compounds, so that the onion will not be quite as sharp, so that its sweeter flavors will come through as opposed to its sharper flavors.

So if you're going to put them raw in a salad or say on top of your burger or something, soaking them in water can help tame their bite. Um, uh,

Huh. So onions have special chemicals inside of them called lacrimators that can make our eyes water. These chemicals are released into the air when you cut onions up. There are some things you can do when you slice onions to protect your peepers, though. Using a sharp knife can help because it doesn't crush the onions as much, so they don't release as many chemicals into the air. Don't try this at home without an adult, though.

Soaking raw onions in water also helps draw out some of their sharper chemicals, too. So they're a little milder. And if all else fails, just try wearing swim goggles. Oh, my guests have arrived. We're going to have so much fun.

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Okay, that one really was the dog. Hey friends, Molly, Sandin, and Mark here with some very big news. Drumroll please. Drumroll.

We're hitting the road in search of adventure, fresh air, and you. That's right. We're going to be live at the Boulder Theater in Boulder, Colorado on Sunday, April 27th. Our science-themed live stage show takes the audience on an adventure through the brain, complete with magic tricks, dance moves, out-of-body experiences, mystery sounds, and a game show. Molly, you almost left out the most important part.

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