The World's Healthiest Foods

More About Onions From Our Newsletter

Did you know that different varieties of onions vary greatly in the amount of health-promoting benefits they deliver? Onions are a major source of both phenols and flavonoids, two types of phytonutrients that numerous population studies have found help protect against cardiovascular disease, cancer and asthma. Recent research shows that the variety of onions you choose, and the way you prepare them, can make a huge difference in the amount of beneficial compounds, and the antioxidant and anti-cancer effects, you receive. In general, the more pungent onions deliver many times the benefits of their milder cousins. Among varieties of onions commonly available in the U.S., shallots were found to have the most phenols, and Western Yellow onions the most flavonoids, such as quercitin, which is noted for its asthma-protective effects. When tested against liver and colon cancer cells, Western Yellow, New York Bold and shallots were most effective in inhibiting their growth. Purple onions also contain anthocyanins, the same compounds found in cardio-protective purple grapes, berries and red wine. Although still good for you, summer onions (such as Walla Walla, Vidalia and Maui Sweet Onions), have a higher sugar content and a lower phytonutrient content, so do not provide the same level of health-promoting properties. (For more on The difference between storage onions and spring or summer onions Read more . Onions