Plant foods like onions have many possible health benefits including reducing the risk of obesity, heart disease, and cancer. There is so many benefits but makes us cry, Why? Let's continue.
Onions are known to make you cry when chopping them. Onions, along with many other plants in the Allium species (garlic is another populer one), absorb sulfur from the soil. When onions are chopped, it ends up breaking cells within the onion, which releases certain enzymes. These enzymes then react with the sulfur, creating amino acid sulfoxides. These, in turn, create the highly unstable syn-propanethial-S-oxide, which is a combination of sulfric acid, sulfur dioxide & hydrogen sulfide. When this Substance, in a gaseous state, comes in contact with the moisture in your eye, it triggers a burning sensetion via the ciliary nerve. When the brain gets a message that threre is an irritant in the eye, such as the above, it then kicks the lachmal glands into overdrive, trying to flush the irritant out of your eye(s) with tears.