When I was a college student doing homestay in Tokyo, I mentioned to my host mother one day that some if my classmates had been passing a cold around, and I hoped I wouldn’t catch it too. “Oh, you should gargle,” she told me.
I was a little skeptic, and not just because she had previously told me that there was a pressure point in my ring finger that would make me feel warm during the winter, which she demonstrated by squeezing it with all her might (it worked in the sense that pain produces a sensation similar to heat). I’d never heard of the theory that just gargling, even with ordinary tap water, would keep you from catching a cold, but it turns out this is a pretty common belief in Japan, which some researchers say is scientifically sound.
The custom of gargling to prevent sickness goes back centuries to the Heian Period, which lasted from 794 to 1185. In Japan, it’s considered to be one of the two common sense ways of not getting sick during the winter, along with washing your hands.
It’s a practice that’s continued through to the current day in Japan, even if it’s something that adults are more likely to conscientiously do. “When I was in elementary school, I hardly ever washed my hands or gargled,” recalled one online commentator, “so obviously, I caught a lot of colds.”
▼ Pictured: Only two of the three components of good, clean fun
“This is something people only do in Japan,” offered another. “In other countries, it’s considered vulgar behavior, and there’s never been any custom of doing it.”
This is sort of a half-truth. Even as a young kid growing up in California, my parents would tell me to heat up a cup of water, sprinkle in some salt, and gargle if I had a sore throat, and it actually did wonders. Gargling with lukewarm tap water is a surprise for many new arrivals to Japan though, and I admit that in the building I used to work in, it freaked me out when employees from other companies would do this in the rest room we all shared, often without bothering to rinse the sink out that thoroughly afterwards.
But could this seemingly odd custom actually be effective in preventing colds? After all, I used to think wearing a cotton mask in public was laughable overkill, but after finding out just how big a difference they make when you’re dealing with hay fever, I literally went out and bought a whole box of the things.
For years, medical researchers have mostly held that gargling wouldn’t do much to prevent a cold, as the viruses that cause the sickness were unlikely to be washed away before being absorbed into the body’s cells. Oddly enough, though, no experiments were done to test the effects of gargling until 2002, when a group of researchers led by professor Takashi Kawamura from Kyoto University decided to evaluate the ingrained home medical practice.
The study participants were separated into three groups, one that gargled with water, another that gargled with an iodine solution, and a third that did not gargle at all.
▼ Warning: Before you agree to spit for some guy and let him take notes on the results, make sure he is in fact an actual scientist, and not just some weirdo.
During the year-long investigation, the third group showed the highest propensity of colds, with a rate of 26.4 infected per 100 individuals. The group that gargled with the iodine solution did only slightly better, with a statistically insignificantly lower infection rate of 23.6 people per 100. However, the group that gargled with water was dramatically more resilient, with only 17 per 100 becoming sick.
Similarly dramatic results were achieved by Tatsuya Noda, a researcher from the Hamamatsu University School of Medicine. In his work with elementary school children, he compared the rate of cold infection among groups that did not gargle and those that did with tap water, a slat solution, and green tea.
Once again, the group that didn’t gargle was the most likely to get sick. Tap water garglers had a lower infection rate, and the salt solution group’s was lower still, but the least likely to become sick were the children who gargled with green tea, as they caught colds at a 70 percent lower rate than those who didn’t gargle at all.
▼ Considering the scalding temperate hot green tea is usually served at, we’re hoping they gave those kids the iced version.
However, the researchers haven’t definitively determined why they got the result they did, so right now the data is circumstantial. Still, it appears there may be some merit behind coming home from the office and gargling after you change out of your work clothes.
But while gargling might be helpful in warding off a cold, there’s still nothing that shows it’s effective in keeping you from getting hit with a case on influenza. The heavier hitting influenza viruses can be absorbed into the cells of the respiratory tract in just 20 minutes, so if you’re planning to keep them at bay through gargling, you’ve got a pretty intense schedule to keep up.
▼ If you insist on going that route, you might want to just keep a spittoon by your desk.
To prevent influenza, doctors are still recommending the things they always have. Get vaccinated, avoid crowds, get sufficient rest and nutrition, observe “cough etiquette,” and keep your hands clean. Although honestly, if you’re old enough to be concerned about catching the flu, you’re old enough to know you should cover your mouth when you cough and wash your hands.
▼ Believe it or not, this man is not necessarily a brain surgeon.