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Does An Onion A Day Keep The Doctor Away?

The same compounds that make people cry when slicing into an onion may also make them a healthy choice.

Onions and garlic are both types of alliums, a genus boasting some 750 different species.

Have you ever wondered why your eyes water when you chop onions?

Like Tear Gas

A misconception is that the smell of onions is not what makes most people cry. An onion gets it distinctive taste from compounds that contain sulfur atoms. When an onion is sliced into, its cells are damaged. That cut triggers a chemical reaction that converts these compounds into an acid that acts like tear gas.

At the same time, the byproducts of this reaction condense to form the molecules responsible for the onion’s pungent odor. In other words, the same chemical reaction that makes people weepy also releases the onion’s smell.

Garlic And Health Benefits

A similar thing happens when garlic is chopped. When it’s still in bulb form, garlic doesn’t smell like much. When it’s minced or diced the garlic’s cells trigger a chemical reaction releases the smell we associate with garlic.

However, no one cries from slicing garlic. This is because the byproducts of the chemical reaction that takes place in garlic are different from the byproducts in onions.

Research suggests that the same chemical that gives garlic and onions their distinctive smell helps them fight off bacteria and fungus and parasites. There might be something after all behind all those reports that garlic and onions are good for people.

Read More:

  • Why Do Onions Make You Cry (YouTube)
  • Exploring The Stinky Science Of Alliums (NPR)

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