Why Do I Cry While Chopping Onions? Here’s The Not-So-Emotional Truth

May 3, 2022 | Eye Health | 0 comments

Onions go great in a lot of things: burgers, salads, chicken pasta…but when you’re chopping them, they can make you cry.

It’s no secret that slicing onions as you prepare your tasty dinner can evoke tears within seconds. But unless you have a strong connection with your vegetables, most people aren’t overly emotional about their onions; there must be something else going on to cause those lids to well up.

The burning sensation is obvious enough once you start cutting onions, and might even feel akin to the symptoms of Dry Eye Syndrome. Are the fumes from chopped onions something to be careful about? Are onions hurting your eyes when they make you cry? Let’s peel the layers off this mystery!

Why Do Onions Make You Cry?

What exactly is in an onion that makes you tear up, and how does it happen?

To understand the cause, we need to don our lab coats and get ready to delve into some chemistry science. Before you bought your onions at the store, they likely started their growth cycle below ground on a farm. While growing underground, onions tend to absorb sulfur from the soil around them to produce amino acids. This helps the plant create amino acid sulfoxides as a byproduct.

a bunch of onions
Fast forward to your cutting board, and something interesting happens when you take the knife to that same onion: as you slice into it, you’re actually cutting into its fibers and letting out the moisture built up inside. This allows enzymes to react with the stored amino acids, ultimately giving birth to a new compound called syn-propanethial-S-oxide. Due to the high volatility of S-oxide, it quickly evaporates into a gas and rises from the onion — right into your eyes!

Once S-oxide encounters your eyes, it mixes with your tears to form a mild sulfuric acid in your eyes. As you might guess, the surfaces of your eyes don’t take kindly to this and seek to retaliate to the burning sensation that soon follows. Your tear ducts then react by producing a high volume of moisture in hopes of flushing out the acidic mixture. Hence, your eyes water!

Are Onions Bad for Your Eyes When You Tear Up?

So then, is the process of crying while cutting onions truly bad for the health of your eyes?

In short, not at all. Although the feeling of onion aroma stinging your eyes isn’t pleasant, rest assured it isn’t doing any permanent harm to your ocular system. Your body is well-equipped to deal with foreign particles and compounds that find their way to your cornea through the air. Nevertheless, the painful burning from onions can certainly aggravate pre-existing dry eye symptoms, leading to quick flare-ups while your meal is in the works. There are a few options to avoid this problem.

half of an onion
Try cutting your onion in a different way to prevent the stinging gases from escaping into the air in the first place. Cutting the vegetable under running sink water works well to keep S-oxide from posing a threat. You can also try using an onion cutter to get the dirty work done with minimal sulfur exposure. Lastly, being careful not to chop the root end of the onion can help protect you, as that’s where the bulk of the sulfuric compounds are usually stored.

If you tend to be onion-sensitive and tear up as soon as you see one, you can always resort to artificial tears to give your tear ducts the upper hand!

Why do I need to attend the onboarding webinar?

 

In the onboarding webinar you’ll learn essential information about using Nanodropper safely and effectively. While the device is simple to use, proper technique is key to ensuring you receive its full benefits. You’ll also have the opportunity to ask our team any questions you may have. We look forward to helping you get started with confidence!

Why do I need to take the onboarding survey?

 

By completing this survey, you’ll provide important information about your current medications, such as cost, bottle usage, and side effects. This helps Nanodropper and MedOne evaluate the program’s success and ensure this benefit can continue to support patients like you in the future. Thank you for your valuable input!

Meet Seema

Scottsdale, AZ

Seema is the Chief Strategy Officer of Kore Power where she leads Strategy and Corporate Development. She previously founded ForeOptics, a management consulting firm specializing in complex transformations; change leadership techniques; and operational turnarounds to help organizations accelerate value capture and unlock business growth and potential. She exhibits deep expertise in designing, streamlining, and managing complex global supply chains and operations.

Meet Chris

Phoenix, AZ

Chris is the Managing Director of Xcellerant Ventures, and CEO of Yoo & Co Accelerators. He is a serial entrepreneur, angel investor, venture capitalist, educator, and developer of new value creation in the Healthcare & Life Sciences industry. Chris has deep knowledge in disruptive technologies and is passionate about seeing great research innovations quickly become fundamental improvements to how we understand health and treat disease.

Meet Katey

Oklahoma City, OK

Katey Letzkus earned her Bachelors in Journalism from Oklahoma State University and is passionate about helping clinics grow and achieve their goals! Through her 14 years of medical sales experience, she has received multiple honors for her work with Plastic Surgeons, Prosthodontists, Oral Surgeons and large med spas to grow their businesses. Her primary goal is to ensure patients with financial hardships receive the eye medications they need while helping businesses save money.

Meet Andrew

New York City, NY

Andrew received his undergraduate degree in Sociology from Temple University in Philadelphia. During his studies, he gained unique insight into various socioeconomic inequities that are affecting our local and global communities. Andrew leverages his diverse work experience to help foster new partnerships and to strengthen existing connections with both patients and eye care professionals.

Meet Brooke

Philadelphia, PA

Brooke received her undergraduate degree in communications and Master’s degree in Public Administration from Florida Gulf Coast University. Brooke was formerly the Executive Director for a Southwest Florida nonprofit offering teen girls leadership and fitness programming. Using her extensive leadership, management, travel and operations experience, Brooke seeks to continue developing new and effective ways to grow the company. Brooke is also leading the charge to build new nonprofit partnerships and expand our mission.

Meet Alena

Washington State

Alena received her degree in chemistry from Western Washington University, fostering her love for all things science and numbers. She uses her analytical background to dive into the data, finding ways to better develop connections with eyecare providers to improve the accessibility and affordability of healthcare.

Meet Robbie

Rochester, MN

Robbie is an entrepreneur and award-winning journalist with a background in marketing and communications. He has contributed to The New York Times, Florida Weekly, and Mayo Clinic's education shield, and was once co-founder and executive editor of a news company in his hometown of Naples, Fla.

Meet Jenny

Tacoma, WA

Jenny’s inquisitive mind and entrepreneurial roots led her to co-found Nanodropper. She recently completed her PhD in pharmacology at the University of Washington, and she has scientific research experience at top academic institutions, including her alma mater Brown University, Harvard Medical School, and UW.

Meet Mackenzie

Denver, CO

Mackenzie is a device design engineer who earned her master’s degree in bioengineering with a focus on technology commercialization from the University of Washington. She is passionate about designing and commercializing solutions to address current healthcare problems, especially to help close health equity gaps.   

Meet Elias

Rochester, MN

Elias is a mechanical engineer specializing in design and prototyping. He loves being involved with startups because they challenge him in new and exciting ways. His broad background includes projects with SpaceX, Spacelabs Healthcare, Kestra Medical Technologies, and McKinstry. His passion is within the biomedical industry, making advances in medical devices.

Meet Allisa

Rochester, MN

Allisa is a physician-entrepreneur and inventor who received her MD from the Mayo Clinic. With a background in Clean Tech, neuroscience, and harm reduction, she is a thought leader in the field of value-based innovation and the visionary behind Nanodropper. Allisa's patient-centered mindset drives Nanodropper's mission. 

Skip to content