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The Health Benefits of Eating Onions

Nothing to cry about

As we’ve discussed here before, garlic has numerous health benefits. The onion is no slacker, though. Research has shown onions to have strong anti-bacterial, anti-inflammatory, and anti-allergic actions, which could be why they are the starting point of choice for the cuisine of so many cultures around the world.

There is also a wide variety of onions, and a recent study shows that all onions are not equal when it comes to their healthful qualities. Researchers sought to determine which varieties had the highest antioxidant qualities, as well as the ability to inhibit cancer cell growth. The varieties included in the study were: shallot, western yellow, New York bold, northern red, empire sweet, western white, Peruvian sweet, Mexico, Texas 1015, Imperial Valley sweet, and Vidalia. (I didn’t even know there were so many.)

The winner was the shallot, a staple in Asian, Mexican, French, and Mediterranean cooking. Shallots had the highest antioxidant activity among the 11 varieties tested, with six times more phenolics than the lowest-ranked onion, the Vidalia.

The shallot also had the greatest effect against liver cancer cell growth, along with the western yellow and the New York bold, although the latter two were the highest ranked against colon cancer cell growth.

Onions get a bad rap for their effect on breath, and their ability to induce tears during meal preparation, but this shouldn’t keep them off your shopping list. To combat the tears when slicing and dicing, chill them for about an hour or so before cutting. This slows the activity of the enzyme that produces the allyl sulfate, which is what causes the tears.

As for that infamous “onion breath,” chew a sprig of parsley after any onion-containing meal.


Bursting the bubble

Q: My husband and I don’t drink soda because we know that the sugar in it is bad for us, but we do drink quite a bit of seltzer water as an alternative. Lately, though, I’ve heard that carbonated drinks are bad for your bones — especially in women. Do I need to kick this habit, too?

JVW: Carbonation is generally not the culprit when it comes to your bones. It’s the phosphoric acid and caffeine in colas and other soft drinks that cause the body to secrete calcium, thereby pulling it out of your bones.

Carbonated water, also known as seltzer water or club soda, is another story. Seltzer is made by infusing the gas carbon dioxide (CO2) into plain water. Once in the water, a mild acid, carbonic acid, is formed. Much of this acid is released when the cap is removed and the pressure is let off. While some of the carbon dioxide escapes with the bubbles, the remaining CO2 is ingested with the water. More CO2 will also exit the body in the characteristic belch associated with drinking any carbonated beverage.

While carbonated water itself does not pose the same risks as soda, it can contain some ingredients that may surprise you. Some flavored seltzer contains sweeteners, and many have added mineral salts to balance the pH. The primary mineral salt is sodium bicarbonate, making it higher in sodium than you might think.

For the most part, an occasional drink of carbonated water is not a problem, especially if it is a brand with no added ingredients. On the other hand, it’s possible that long-term consumption of large quantities (even without the added ingredients) may pose a health problem down the road. Although it may be boring advice, moderation is generally the key to safeguarding your health, even with more benign habits. Alternate your consumption of carbonated water with what the Europeans call “flat” bottled water and you should be fine.


What is…quercitin?

Quercitin is the natural flavonoid behind onions’ anti-inflammatory and anti-allergic effects. It can also improve cardiovascular health, prevent the oxidation of LDL (bad) cholesterol, and even reduce risk for cancer.

The anti-inflammatory action of quercitin is caused by the inhibition of enzymes, such as lipoxygenase, and the release of histamine, which causes congestion. Dr. Wright includes quercitin in his list of supplements to arm you against the risk of prostate, ovary, breast, and colon cancer at a dose of 1,000-1,500 mg/day. Some more aggressive anti-cancer plans have suggested taking as much as 1,500-3,000 mg/day. Check with your doctor if you’d like to increase your quercitin intake.

Yours in good health,
Amanda Ross
Managing Editor
Nutrition & Healing

Yang J, Meyers KJ, van der Heide J, Liu RH. “Varietal differences in phenolic content and antioxidant and antiproliferative activities of onions.” J Agric Food Chem 2004; 52(22): 6,787-6,793.