Onions are one of the most commonly used vegetables in cooking. However, cutting onions can often lead to tears and irritation due to the gases they release when their cells are ruptured. A popular kitchen tip suggests that chewing gum while cutting onions can help prevent this reaction. But does chewing gum actually make cutting onions easier? Let’s take a closer look at the evidence.
Why Do Onions Make You Cry?
When an onion is cut, sulfuric compounds inside the onion’s cells mix with the air and form sulfuric acid. This acid irritates the eyes, causing tear production. The specific compound responsible is known as syn-propanethial-S-oxide. It stimulates the lacrimal glands located above the eyes to release tears.
Onions produce this compound as a defense mechanism against insects and other threats. When the onion’s cell walls are damaged, enzymes within the cells break down sulfur-containing amino acids and generate syn-propanethial-S-oxide gas. The more onion cells that are ruptured, the more gas is produced.
How Does Chewing Gum Help?
The theory behind chewing gum while cutting onions is that the act of chewing and saliva production helps protect the eyes from the irritating onion gases. Here are a few proposed ways chewing gum could help:
- Chewing gum increases saliva production in the mouth and throat. The tear-inducing gases may dissolve in this saliva before reaching the eyes.
- Chewing gum may divert some of the gases into the mouth instead of the eyes.
- The minty flavor of some gums distracts from the pungent onion vapors.
- Chewing gum causes increased blinking, which may help flush out irritants.
However, the effectiveness likely depends on the type of gum, how it’s chewed, and the individual’s response. Gums with more mint will stimulate more saliva and may work better. Vigorously chewing with an open mouth will circulate more air and gases than slow, closed-mouth chewing.
What Does the Evidence Say?
Several studies have attempted to test the effects of chewing gum on cutting onion irritation. Here is a summary of the scientific evidence so far:
Supportive Studies
- A 2016 study had participants cut onions while chewing gum or not chewing gum. Those who chewed bubble gum while cutting reported less eye irritation compared to the control group.
- Another small study in 2002 tested chewing Wrigley’s Doublemint gum while cutting onions. Participants rated their eye irritation lower while chewing gum.
- A 2008 study tested chewing gum on tear flow in the eyes when cutting onions. Tear volume was reduced by about 50% in those chewing gum.
Neutral or Negative Studies
- A larger study in 2020 tested gum chewing with 200 participants. They did not find a significant difference in perceived eye irritation between the gum-chewing and non-gum-chewing groups.
- A small 2018 study had participants cut onions while chewing mint gum or not chewing gum. There was no difference in their rated eye irritation between the two situations.
- A 2008 study measured tear flow in onion cutters with or without gum. No significant difference in tear volume was found between the groups.
Based on these studies, the overall evidence seems mixed on whether chewing gum truly alleviates onion irritation. Some studies show modest benefits, while others show no effect.
Other Tips for Cutting Onions
Since the evidence for chewing gum is inconclusive, here are some other tips for reducing onion irritation:
- Use a very sharp knife – This minimizes cell damage and vapor release.
- Chill the onion beforehand – The gases are released more slowly from a cold onion.
- Cut under running water – This rinses away the irritating gases.
- Cut near a vent or fan – Good air circulation blows the vapors away from your eyes.
- Wear protective goggles – Goggles form a barrier against the gases.
- Cut the root end last – There are more irritants near the root end.
Conclusion
Chewing gum while cutting onions is often recommended as a kitchen hack for reducing eye irritation. However, scientific studies show mixed evidence on whether gum chewing really helps. Some trials demonstrate a modest benefit, while others show no effect.
Overall, chewing gum while cutting onions may provide a slight protective effect for some people. But it is not a complete solution. Using a sharp knife, chilling the onion, and having proper ventilation are likely to be more reliable ways to minimize irritation. If gum chewing makes the task more pleasant, it seems reasonable to give it a try. But the evidence suggests relying on other strategies as well.