Why Do Onions Make Us Cry?

Answer 1

When you cut into it, you release a gaseous sulfur-containing chemical called the lachrymatory factor (propanthial S-oxide) that spreads in the air and comes into contact with your eyes."The lachrymatory factor activates the nerve endings of pain fibres in the top layer of the cornea," explains Professor Jonathan Dostrovsky, director of U of T's collaborative program in neuroscience and a professor in the Department of Physiology. "When these pain fibres become active, they send signals to the brain and give rise to the sensation of pain in the eye," he says. "At the same time, these signals also activate the part of the autonomic system [the system responsible for the optimal functioning of the body] that controls the lacrimal gland [the gland that produces tears] leading to increased production and release of tears."

The same effect is produced, he notes, when other types of toxic or irritating chemicals -- such as a squirt of lemon juice or drop of shampoo -- get in the eye. The pain leads us to avoid or minimize further contact with these chemicals; the increasing tearing helps to wash away the irritating chemicals.

Answer 2

The fumes irritate your sinus and make your eyes water. You can refrigerate them to reduce this. Also try using a chopping device like a mandolin, food processor or one of those "instant Salsa" things. The quicker you get the cutting done the less gas and liquid you release and the less you will cry. Good Luck!

Answer 3

Hello, ComicBookHeroe,

I was also wondering about that, and I found a great video explaining why and also how to avoid it:

http://thoughtsandtips.blogspot.com/2007/09/onions-everywhere.html

Answer 4

that's not the good scent of the onion that makes us cry, however the gas that the onion releases as quickly as we sever this member of the lily family contributors.The onion itself includes oil, which includes sulfur, an irritant to the two our noses and to our eyes

Answer 5

It's probably a defense mechanism.

That water idea seems brilliant! I'm going to try it tonight. My eyes water up so badly my makeup smears everywhere, and my three-year old son gets extremely worried. I've even tried using sunglasses, which didn't help.

Answer 6

they release sulphur when you slice them, which reacts with the water already in our eyes to produce a chemical which irritates them. Try cutting them underwater, this always helps!

Answer 7

I think they realese some kind of cemical

Answer 8

Because there so ugly.

Answer 9

Here you go. :>)

Answer 10

idk it doesn't happen to me