Rich source of antioxidants. Red onions contain a higher amount of antioxidants and flavonoids than the yellow or white onion, and they’re a rich source of quercetin. Quercetin is a powerful antioxidant with anti-inflammatory properties that may help fight chronic diseases such as heart disease and cancer and it is beneficial for eliminating free radicals in the body. It may also prevent the release of histamine, making onions a natural antihistamine.
Antibacterial. Onions may act as powerful anti-bacterial by inhibiting the growth of harmful bacteria such as E. coli, Helicobacter pylori and S. aureus (staph) and Cholerae.
Anti-inflammatory. Onions act as powerful antioxidants which stimulate immune responses and reduce inflammation in our bodies.