ONIONS – and their outstanding health benefits | Blog | Foodwise

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ONIONS – and their outstanding health benefits

Onions contain organic sulfur compounds that have powerful antioxidant, detoxifying and anti-cancer properties. But to reap the maximum benefit you should be eating them raw – at least part of the time! That’s because sulphur compounds are partly destroyed by heat.

Detox Power

They also contain specific amino acids methionine and cystine that, among other things, are very good at detoxifying your body from heavy metals. In fact, they are chelators, compounds that can latch on to mercury, cadmium and lead and escort them out of the body.

Vitamin C

Onions are also an excellent source of vitamin C – effective in removing lead, arsenic and cadmium. The flavonoids in onion tend to be more concentrated in the outer layers of the flesh. To maximize your health benefits, peel off as little of the fleshy, edible portion as possible when removing the onion's outermost paper layer.


Polyphenols are one of the largest categories of phytonutrients in food and onions have lots! The total polyphenol content of onion is not only higher than the other allium vegetables, garlic and leeks, but also higher than tomatoes, carrots, and red bell pepper. In the Mediterranean diet, only six vegetables (artichoke heart, parsley, Brussels sprouts, shallot, broccoli, and celery).


Onions are a good source of quercitin is a flavonoid that is anti-inflammatory, antibiotic, antiviral, thought to have diverse anti-cancer powers. It is also a sedative. Quercetin has been shown to thin the blood, lower cholesterol, raise good-type HDL cholesterol, ward off blood clots, fight asthma, chronic bronchitis, hay fever, diabetes, atherosclerosis and infections and is specifically linked to inhibiting human stomach cancer.

Clever Tip: When onions are simmered to make soup, their quercetin does not get degraded. It simply gets transferred into the water part of the soup. By using a low-heat method for preparing onion soup, you can preserve the health benefits of onion that are associated with this key flavonoid.

Interested in improving your overall health through diet and lifestyle? It’s easy with the Foodwise Immune Boost Plan: https://www.foodwise.life/program/immune-boost


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