Onion is a powerful anti-septic that is rich in vitamins A, B and C. It is a potent source of folic acid, calcium, phosphorus, magnesium, chromium, iron and dietary fiber.
Ancient records reveal that onions have been used as far back as 4000 B.C. as a cure-all for many illnesses. Even now, we find many medicinal properties from this dynamite bulb.
For an amazing and extensive list of the onion's beneficial properties as an anti-coagulant, anti-infammatory, anti-septic, in treating anemia, high blood pressure and high cholesterol and many other health benefits, including that the onion is a potent aphrodisiac, see here.