Why do onions make you cry?

Question

Everytime I chop up onions I get tears and have to go out of the room to get away from it and then my mum continues lol! Why do they make you get tears?

Answer 1

Cos they're nasty! Kidding, I'm not sure exactly what it is, but the next time you cut onions, have something over your nose and you will not cry or will cry way less! The smell of the onions going into your nose is what actually makes you cry!

Answer 2

(m)

When you slice through an onion, you break open a number of onion cells. Some of these cells have enzymes inside of them, and when they are sliced open, the enzymes escape. The enzymes then decompose some of the other substances that have escaped from sliced cells. Some of these substances, amino acid sulfoxides, form sulfenic acids, which then quickly rearrange themselves into a volatile gas.

The gas reaches your eyes and reacts with the water that keeps them moist. This changes the chemical's form again, producing, among other things, a mild sulfuric acid, which irritates the eyes. The nerve endings in your eyes are very sensitive and so they pick up on this irritation (this is why our eyes sting when we slice onions). The brain reacts by telling your tear ducts to produce more water, to dilute the irritating acid so the eyes are protected. Your other reaction is probably to rub your eyes, but this will actually make the irritation a lot worse, of course, if you have onion juices all over your hands.

Oddly enough, this volatile compound is also responsible for a lot of the great taste in onions, as well as the pleasant aroma when you cook the vegetable. You'll also get sulfenic acids by cutting up garlic, chives and leeks, among other vegetables, but they don't form the same irritating gas, just a strong smell.

There are all kinds of remedies for dealing with this irritating phenomenon, some more effective than others. As a general rule, move your head as far away from the onion as you can, so the gas will mostly disperse before it reaches your eyes. If you really can't stand the tears, the simplest solution might be to wear goggles. This measure is very effective, but it may seem a bit extreme to those around you, and if your kitchen is steamy, you might not be able to see what you're doing (never a good idea when you're using a knife).

Peeling the onion and then chilling it in the refrigerator before you slice it will minimize the release of gas somewhat, because the change in temperature alters the compounds in the onion. Cooking an onion before you slice it will work also, for the same reason. Another easy solution is to cut the onion under water or run the tap over it as you slice.

Some people say if you hold a lemon, piece of bread or a sugar cube in your mouth, the food will absorb the gas before it reaches your eyes. Breathing with your mouth, instead of your nose, might also help because as you inhale, you suck the gas in and as you exhale, you blow it away. This keeps a lot of the gas from ever reaching your eyes.

Answer 3

Because the sap of the onion irritates you eyes. Tearing is a natural reaction of your body to clean the eye from dust, and other substances that could harm the eye.

Answer 4

I think its because they are such a cute vegtable its very difficult not to feel sorry for them while you chop them up...hence the tears.

Answer 5

Onions always make me Cry... :(

not v .nice things!!

Answer 6

because of its odor. if you smell that it will react and your eyes irritate.

Answer 7

cos ur abt to cook them

Answer 8

because of its odor, it makes you cry

Answer 9

They're very very sad.