Onions Fact Sheet

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Onions are members of the Allium family, together with garlic, shallots, chives and leeks. It has been used as a food source for thousands of years and is a dominant vegetable crop in most countries across the world, and has numerous health benefits.


Health Benefits of Onions

Onions are low-calorie vegetables that contain vitamins and minerals: B vitamins, vitamin C, phosphorus, and potassium. The green tops of spring onions are a good source of vitamin C and beta-carotene.

Onions contain adenosine, a substance that can prevent blood clotting, which may help prevent heart disease. Onions also contain quercetin, a potent antioxidant, as well as sulfur compounds, which help lower cholesterol.

The more phenols and flavonoids onions contain, the higher antioxidant and anticancer activity they provide.

Buying and Storing Onions

Look for onions that are heavy in your hand, and very firm to the touch. They are the freshest. Then, smell the onions: if they have a strong odor, they may have passed their peak and will probably not be very tasty.

Very cheap onions are often spread with pesticides and are of a low quality. Prefer quality conventionally grown onions or organically grown ones.

Onions can be stored in a cool, dry and dark place for several months if they are organic, and for about 2 to 3 weeks if not.

Once they are cut, wrap leftovers and store them in the refrigerator. They will keep for a couple of days.

Preparing Onions

Onions make you cry when you cut them because they release sulfur compounds and enzymes that form sulfenic acids, which cause our lachrymal glands to become irritated.

Fortunately, there are ways to cut down on the tears:

  • You can use a very sharp knife, which will limit cell damage and the release of enzymes.
  • You can chill onions prior to cutting them; this will prevent enzymes from activating.
  • Last, you can cut onions in water, which will prevent irritating gas from reaching your eyes. Simply wearing a pair of glasses may also help by providing a protecting screen to the eyes.

Onions can be eaten raw or cooked. They can be paired with garlic, ginger or tomato. They can be added to salads and sandwiches, to all kinds of dishes including soups, stews and stir-fry dishes.

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  1. Hi, Anne,

    I have a question but I am afraid its not about onions.

    “Is it safe to eat (or drink juice of) raw beat roots ?”
    how much of it is safe and what do we get out of it?
    Thank you.

    • Hi Dorah,
      I have some good info about beets here but my answer to your Q. is this: eating raw beet root is great, up to one per day, grated, is fine. You can make a salad with other veggies, too. Juicing raw beet root may not be such a great idea because of the sugar in beets, that could cause spikes in blood sugar. I’m not a huge fan of juicing unless it’s for medical reasons. Much better to grate your beet, you get all the nutrients including the fiber, which we all need more of anyway. Hope this helps.


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