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10 Superfoods

The potential health benefits of onions won't make you cry.
The potential health benefits of onions won't make you cry.

One of civilization's oldest medicines, onions have also been used to pay rent and congratulate newlyweds. Onions are rich in antioxidants and are possibly one of the best cancer-fighting foods you can eat. Shallots and red and yellow onions are the richest dietary source of quercetin, a potent antioxidant. The numerous anti-cancer agents in onions are effective against:

  • Cancer of the mouth
  • Throat cancer
  • Lung cancer
  • Stomach cancer
  • Colorectal cancer
  • Breast cancer
  • Ovarian cancer
  • Prostate cancer
  • Liver cancer [source: Galeone]

Eating plenty of onions can reduce your risk of throat cancer by 88 percent and prostate cancer by 71 percent [source: La Puma]. People who live in Vidalia, Ga., home of the Vidalia onion, have one-third the rate of stomach cancer as the rest of the U.S. [source: Carper].

They're also good for your heart. Onions lower cholesterol and blood pressure. They contain anticoagulants that thin blood and reduce clogging of the arteries. Onions can even block the blood-clotting activity that fatty foods produce.

Onions are a centuries-old and research-proven treatment for diabetes. Cooked or raw, onions depress blood sugar. The more onions you eat, the greater the effect.

They'll help fight a number of other ailments, too. Onions are naturally antibiotic, antiviral, antiseptic and anti-inflammatory. They help dilate bronchial tubes, making breathing easier for mild asthmatics, hay fever sufferers and people with chronic bronchitis. Onions can even help you deal with stress. Quercetin is a mild sedative that induces relaxation and sleep.

Find out about the health benefits of fish on the next page.