Eyes Burning Hours After Cutting Onions

The Persistent Sting: Eyes Burning Hours After Cutting Onions

Every time I have to cut onions, my eyes burn and water. It's a familiar scenario for many of us. The pungent aroma of onions fills the kitchen, but the tears in our eyes have nothing to do with the delicious meal we're preparing.

Why do onions make our eyes burn, and why does this discomfort linger for hours after we've finished cutting them? In this detailed exploration, we'll uncover the science behind the tearful ordeal and discover ways to alleviate the stinging aftermath.

Plus, we'll introduce you to a promising solution that's in development - "The Laughing Onion."

Why Do Onions Burn My Eyes?

The burning sensation in our eyes when we cut onions can be attributed to a chemical reaction that occurs when the onion's cell walls are damaged. Here's how it happens:

  • When we slice into an onion, we release its volatile compounds into the air.
  • One of these compounds is syn-propanethial-S-oxide, a volatile sulfur compound.
  • When it comes into contact with the moisture in our eyes, it forms sulfuric acid.

This sulfuric acid is the culprit behind the burning sensation. Our eyes produce tears as a defense mechanism to wash away the irritant, which is why they water when exposed to onion vapors.

The Lingering Discomfort

While the initial burning and tearing typically subside after a few minutes, some people experience discomfort for hours after cutting onions. This extended irritation can be attributed to several factors:

  • Exposure to a High Concentration of Onion Vapors: If you're in a small, poorly ventilated space while cutting onions, you're more likely to inhale a higher concentration of onion vapors, which can lead to prolonged eye irritation.

Onion gas causing eyes to burn

  • Sensitivity to the Compounds: Individuals vary in their sensitivity to the compounds released by onions. Some people may be more prone to eye irritation and experience longer-lasting discomfort.

  • Touching the Eyes: Accidentally touching your eyes with hands that have come into contact with onion residue can prolong the burning sensation.

Alleviating the Sting

Here are some practical steps you can take to reduce eye irritation after cutting onions:

1. Wash Your Hands: After cutting onions, thoroughly wash your hands with soap and water to remove any onion residue. This will prevent the transfer of irritants to your eyes if you inadvertently touch them.

Washing hands to prevent burning eyes from cutting onions

2. Avoid Touching Your Eyes: Be conscious of not touching your eyes, even if they start to water. Rubbing your eyes with onion residue on your hands can exacerbate the burning sensation.


3. Use an Eye Rinse or Cool Water: If your eyes are more irritated than usual, consider using an eye rinse or flushing them with cool, clean water. This can help soothe the discomfort.

Wands cupped with water ready to flush burning eyes from onions

4. Consult an Eye Doctor: If the burning sensation persists for longer than a few minutes or if you experience severe discomfort, consult your eye doctor or optometrist. They can assess your condition and provide appropriate treatment.

Consulting doctor if eyes burning for hours after cutting onions

The Laughing Onion: A Promising Solution

While the methods mentioned above can help alleviate the discomfort caused by cutting onions, they don't offer a guaranteed solution to prevent it. That's where "The Laughing Onion" comes in.

A Tear-Free Future

"The Laughing Onion" is currently in development and aims to be the first guaranteed way to stop an onion from making you cry. While the exact details of its technology remain under wraps, it holds the potential to revolutionize the way we handle onions in the kitchen.

Click here to Join the Waiting List

If you're tired of the lingering discomfort and tears that follow the simple act of chopping onions, you can sign up for the waiting list here. Get ready to cut your onions without the burning and say hello to a happier, more enjoyable cooking experience.

In Conclusion

The burning and tearing of eyes when cutting onions are a common culinary inconvenience, but they're not without scientific explanation. The reaction between onion compounds and our eye's moisture leads to the stinging sensation. While this discomfort typically subsides after a few minutes, some individuals experience prolonged irritation due to various factors.

Practical steps like washing your hands, avoiding eye contact, and using an eye rinse or cool water can help alleviate the discomfort. However, the ultimate solution for tear-free onion cutting is still in development with "The Laughing Onion." As we eagerly anticipate its release, the kitchen may become a place of joy, free from the persistent sting of onion vapors. Happy cooking, and may your eyes remain dry!


Frequently Asked Questions

Question 1: Can onions damage your eyes?

No, but onions can cause eye irritation when chopped or sliced. When you cut into an onion, it releases a gas called syn-propanethial-S-oxide. This gas reacts with the moisture in your eyes to form a mild sulfuric acid, which irritates the eyes and stimulates tears. While this irritation can be uncomfortable, it typically isn't harmful and usually subsides once you're no longer exposed to the onion fumes. Some people end up wearing goggles or chilling the onion before cutting despite these methods not being a the best or most effect way. The Laughing Onion is a product that is the only guaranteed way to prevent onions from causing eye irritation.

Question 2: Why are my eyes so senstive to onions?

Individual sensitivity to onions can vary for a few reasons:

  1. Genetics: Some people may have a genetic predisposition to be more sensitive to the compounds released when onions are cut. This sensitivity can affect how their eyes react to the irritants produced.

  2. Tear production: People who produce more tears or have more sensitive eyes may experience stronger reactions to onion fumes. Tear production can vary from person to person, affecting how quickly the eyes can flush out irritants.

  3. Allergies: While rare, some individuals may have an allergy to onions or to specific compounds found in them. Allergic reactions can vary widely in severity and may include symptoms beyond eye irritation, such as itching, swelling, or difficulty breathing.

  4. Exposure: Regular exposure to onions or other similar substances can sometimes desensitize individuals over time. Conversely, infrequent exposure may make someone more susceptible to irritation.

  5. Environmental factors: Factors such as humidity, ventilation, and the freshness of the onion can also influence how strong the fumes are and how much they affect someone's eyes.

Overall, individual sensitivity to onions can depend on a combination of genetic factors, tear production, allergies, exposure, and environmental conditions.

Question 3: How to stop your eyes burning from onions?

Prevention is the best way to stop your eyes burning from onions. Below is a list of the most common methods people have tried to do so. None of them are completely effective except The Laughing Onion.

There are several methods you can try to reduce or prevent eye irritation when chopping onions:

  1. Chill the onion: Cooling the onion in the refrigerator for about 30 minutes before chopping can slow down the release of the irritating compounds, potentially reducing eye irritation.

  2. Use a sharp knife: A sharp knife causes less damage to the onion's cell walls, resulting in fewer irritants being released.

  3. Cut under running water: Chopping onions under a stream of cold water can help wash away the irritants before they reach your eyes.

  4. Cut near a flame: Some people find that cutting onions near a flame, such as a gas stove or candle, can help neutralize the compounds that cause eye irritation. However, be cautious when using this method to avoid injury.

  5. Wear goggles or glasses: Protective eyewear can create a barrier between your eyes and the onion fumes, preventing irritation.

  6. Use a fan or ventilation: Positioning a fan or opening a window to create airflow can help dissipate the onion fumes, reducing the concentration around your eyes.

  7. Breathe through your mouth: Breathing through your mouth while chopping onions can help reduce the amount of onion gas that reaches your eyes.

Experiment with these methods to find what works best for you. We have tried all of these methods without any significant reduction in our eyes stinging when cutting onions.

Question 4: Why do onions burn your eyes?

When you slice into an onion, you unleash a potent mix of compounds that can make your eyes sting and tear up. This reaction occurs because cutting the onion releases amino acid sulfoxides, which then interact with enzymes to produce sulfenic acids. These acids swiftly transform into syn-propanethial-S-oxide, a volatile gas. When this gas encounters the moisture in your eyes, it forms sulfuric acid, triggering the burning sensation and causing your eyes to water as a protective response. So, why do onions burn your eyes? It's all about the chemical reaction that happens when you cut into them!

Question 5: Can onion gas reach my eyes through my nose and make my eyes burn when I cut an onion?

Yes, it's possible for onion gas to reach your eyes through your nose and cause irritation. When you cut onions, volatile compounds like syn-propanethial-S-oxide are released into the air. These compounds can be inhaled through your nose, and if they come into contact with the moisture in your nasal passages, they may trigger irritation or a burning sensation in your eyes. Additionally, some of these compounds may travel through the nasal passages and reach the tear ducts, further contributing to eye irritation.

Check out our blog post on which onion makes you cry the most.

We bought and tested the three most common onion goggles and wrote a blog about our findings

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