Sorry: Onions won’t prevent the flu

It sounds like such a simple solution for fending off the dreaded flu: Leave a peeled onion around your house, and it’ll absorb any flu virus that’s flying around.

Not so much, says Kim Reddin, the director of public and industry relations at the National Onion Association (yes, it exists). She says the rumor is an old wives’ tale that has taken on new vigor in the wake of this year’s flu epidemic.

“For you just to cut an onion open and have something leap onto it, germs don’t behave that way,” she says. “They have to live in some moist environment. There isn’t any food product that’s a magnet [for] bacteria.”

Reddin is quick to dispel a chain letter that’s currently circulating, saying that the “facts” in it — that leftover onions are poisonous and that leaving them out is a way to fight off the flu — came from different sources. The idea of leftover onions being poisonous came in 2008 from a blogger who had her facts wrong about food safety. In 2009 or 2010, Reddin says, the second claim was added to the letter: that a peeled onion can absorb the bacteria that leads to the flu.

“There’s no scientific evidence that this really works,” she says. “This stems from a very old wives’ tale, before people even had discovered what these bacteria were. They believed that putting garlic and onions in your home was a way to fight off evil spirits, vampires and illnesses.”

We double-checked with Massachusetts-based microbiologist Dr. Ted Myatt, who was quick to second Reddin’s thoughts.

“[It's] pure fiction, as you might imagine. The thought [was] that the plague was caused by ‘noxious air’ and that the onions absorbed the bad air. After the plague, this same remedy was used for smallpox and influenza. But unfortunately, onions do not absorb microorganisms and can not ‘purify’ the air.”

But there is one piece of information in the aforementioned chain letter is indeed true: that onions are harmful to dogs.

“Dogs and cats can get extremely ill if they eat onions, and the bottom line is your pets should not eat table scraps,” Reddin says.

Now, she is working to reach as many people as possible to clear up the other myths:

“It just ended up turning into something that I don’t think anybody could have possibly imagined, but that’s what happens sometimes with the Internet,” she says.