Why do onions make you cry?


Why do onions make you cry? Uncover the scientific mystery behind those onion-induced tears. Prepare to be amazed!


Published: February 8, 2024 · Modified: February 8, 2024 by Jennifer Ryan

Why do onions make you cry?

Ah, the humble onion – a kitchen essential that adds depth and flavor to countless dishes. Yet, for all its culinary charm, there’s one undeniable drawback: the tears. As someone who has battled the stinging sensation and watery eyes while chopping onions, I embarked on a quest to uncover the science behind this kitchen mystery. Join me as we unravel the tearful tale of why onions make you cry and discover some tricks to minimize the waterworks.

Why do onions make you cry?

The Tearful Tale of Onions

The Culprit

At the heart of the onion-induced tears lies a fascinating biochemical process. Onions contain sulfur compounds, which, when cut or chopped, release a volatile gas known as syn-propanethial-S-oxide. This gas reacts with the moisture in your eyes to form a mild sulfuric acid, triggering the eye irritation and the ensuing tear production.

The Eye's Defense Mechanism

Our eyes have a remarkable defense mechanism against foreign substances. When an irritant, such as the sulfuric acid produced by chopped onions, comes into contact with the eyes, tear glands kick into action. The tears are designed to flush out the irritant and protect the delicate surface of the eyes.

Why do onions make you cry?

Minimizing the Waterworks

While we can’t entirely escape the onion-induced tears, there are practical strategies to minimize the discomfort:

1. Chill the Onions

Pop your onions in the refrigerator for about 30 minutes before chopping. The cold temperature slows down the release of the volatile compounds, reducing the intensity of the eye irritation.

2. Use a Sharp Knife

A sharp knife produces cleaner cuts, minimizing cell damage and the release of irritants. Dull knives, on the other hand, crush more cells, releasing more of the sulfur compounds and intensifying the tearful experience.

3. Cut Near Running Water

Position your cutting board close to a running tap. The water helps disperse the irritant gas away from your eyes, providing a makeshift barrier against the tears.

4. Embrace Ventilation

Cooking in a well-ventilated kitchen can help disperse the onion vapors. Turn on your stove’s exhaust fan or open a nearby window to allow the irritating gases to dissipate.

5. Wear Onion-Cutting Goggles

For a foolproof solution, invest in a pair of onion-cutting goggles. These specialized glasses create a barrier between your eyes and the onion vapors, keeping your vision clear and tear-free.

In the grand tapestry of culinary experiences, the onion’s ability to bring tears to our eyes is a quirky but unavoidable chapter. Armed with the knowledge of the science behind the tears and a few practical tips to minimize the waterworks, you can now approach onion chopping with newfound confidence. So, the next time those tears start flowing, remember: it’s not you; it’s the science of onions at work! For more food facts follow us on social media where we share new food content every week.