Why Onions Make Your Eyes Water and How to Deal With It: Does Plugging Your Nose Work?

Onion, also known as bulb onion, round onion, jade onion, onion head, Dutch onion, and foreign onion, is a classic delicacy on the dining table. But onions are rather special, often making friends who chop them both love and hate them. So why do onions make your eyes water? How do you deal with onions making your eyes water? What benefits does eating more onions have?

1. Why do onions make your eyes water?

Onions make us cry because they release a chemical called lacrimatory factor, which irritates our eyes. Simply peeling an onion will not make us cry. But if you chop, cut, crush or press it, the onion's cells break open, allowing two substances that are normally kept separate to mix and become a powerful chemical weapon similar to tear gas.

The lacrimatory factor evolved as a defense mechanism, allowing the onion to resist attack by microorganisms and by animals like us. Damaging an onion essentially causes it to begin defending itself: as the cells rupture, chemical reactions are activated.

Inside an intact onion cell, a molecule called a sulfenic acid precursor floats in the filling fluid.

Also floating in the cytoplasm is a sac called a “vacuole”, which contains a protein called alliinase. The two are originally kept separate, but damaging the cell mixes them together into a chemical weapon.

Onions contain fisetin, and fisetin can activate signaling pathways in the differentiation of nerve cells, helping to promote the formation of human memory. Eating onions regularly can strengthen the connections between nerve cells and store certain memories in the human brain, so regularly eating onions is very good for enhancing memory.

2. How do you deal with onions making your eyes water?

1. Put it in water after cutting

Onions make your eyes water because after being cut they release a volatile substance that stimulates tear secretion. Fortunately, this substance is soluble in water, so you can quickly cut the onion into two halves, soak them in cold water, let all the eye-irritating substance dissipate, and then take them out to cut without your eyes watering.

2. Cut it in water

Actually, this method works on the same principle as the one above, only it is a bit quicker since you operate directly in the water. It works, but it demands a bit more patience. When cutting, be careful not to cut your hand; operating in water is harder, so be more careful.

3. Plug your nose

When the nose inhales the volatile substances from the onion, it also feels very pungent, and then it also irritates the eyes. Our nose is generally a bit closer to the onion, so you need to block this channel that irritates the eyes. Plug your nose with a tissue and then cut the onion. Although it is not elegant, it is still effective.

4. Heat it in the microwave

Heat the onion in the microwave for several tens of seconds, so that the substances inside change somewhat. When you cut it again, there will be no such volatile substances, and it will not irritate your eyes so much. When heating, peeling the onion first works a bit better. The main thing is to eliminate those eye-irritating substances.

3. What benefits do onions have?

Anti-cancer effect. Onions contain quercetin and prostaglandin A; these two components have anti-cancer effects. Quercetin has a certain effect on inhibiting the activity of cancer cells, while prostaglandin A has the effect of dilating blood vessels. After eating, it lowers blood viscosity and has a certain effect on lowering blood pressure and preventing thrombosis.

Preventing colds. Because onions contain allicin, and allicin has the effect of fighting influenza viruses, eating them has a certain effect on preventing colds.

After eating onions, when the allicin in them is excreted through the respiratory tract, sweat glands, and urethra, it also has the effects of expelling phlegm, inducing sweating, and promoting urination.

Lowering blood sugar, because onions contain a component similar to the anti-diabetic drug tolbutamide. After eating, it can produce phlorizin in the body, and phlorizin has a strong diuretic effect. Diabetics who regularly eat onions gain a certain effect of lowering blood sugar and promoting urination.

Refreshing effect, because after onions are absorbed in the intestines, they can help human cells make better use of glucose, supply energy to brain cells, and at the same time have the effect of lowering blood sugar. For people who are listless, onions can be used as a refreshing food therapy.