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In Japan it is sometimes said that to cure common cold a remedy is to wear a warm green onion (Allii Fistulosi), around the neck. This practice is not as popular as before, but still many other articles about the topic can be found on the Internet.

風邪 長ネギ 首

Any study proving how effective this is?

The theory is for instance reported in a guide by mainstream media company OKwave:

ネギには硫化アリルという成分が含まれており、抗菌・殺菌作用があるんだそうです。 首に巻くと、硫化アリルが口や鼻から吸収されて、鼻やのどを殺菌してくれるのだそうです。


"Green onion cures common cold": The old saying is actually true!
It is said that in green onion there is an allyl sulphuration component, which has an antibacterial/antimicrobial and bactericidal/germicidal action, and by wrapping it around the neck, the allyl sulphuration is absorbed via the mouth and nose, which sterilizes the nose and throat.

Another article focuses on simply alleviating the symptoms of common cold:



Most people think that wrapping a green onion around the neck means that substance gets into the threat by contact, but in fact the most efficient way the substance enters the body is by gas from the wrapped green onion. The scent of the green onion has components that act as anti-inflammatory and sterilizer, allowing nerves to relax allowing better sleep.

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Are you looking for the specific treatment in question, or just scallions in general? – rjzii Apr 3 '12 at 16:54
@RobZ: specifically about warm ones around the neck. – nic Apr 4 '12 at 1:13
The article says, "to soothe the nerves to induce to sleep": so perhaps the claim is that it 'alleviates symptoms' of a cold, not that it 'cures' a cold. – ChrisW Apr 13 at 10:05
The claim is not that leek cures common cold, but that helps healing. Seems like nitpicking but this difference makes the current answer off topic. Please do not misquote claims – Sklivvz Apr 13 at 13:03
You can fix this question in one of two ways. Provide evidence that it is believed that warm green onion is believed to cure the common cold or modify the question so it correctly represents the beliefs it questions ("Does leek alleviate common cold symptoms?" or similar). – Sklivvz Apr 13 at 13:06

2 Answers 2

up vote 1 down vote accepted

See Common Cold Centre at Cardiff University which says

There may never be a cure for the common cold!

It is very unlikely that we are going to see a cure for the common cold because of the following problems-

• Common cold is not a single disease but a syndrome of symptoms caused by many different viruses. Defeating smallpox with a single vaccine was a relatively easy task compared to developing multiple vaccines for common cold

• By the time you know you have a cold it is probably too late to treat, as antivirals need to be taken 24-48 hours after onset of symptoms

amongst other reasons.

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I don't think a categoric answer on the common cold helps here. It would be more interesting to know about the actual effects of green onions. – Christian Jun 4 '13 at 12:08

The best I can say, is that there are various studies regarding the anti-inflammatory and analgesic properties of all the allium family, including the scallion.

analgesic and anti-inflammatory effects of the Allium Ascalonicum (scallion)

In conclusion this study has shown that the acqueous and methanol extracts of Allium ascalonicum have mild analgesic activity and strong anti-inflammatory activities.


Antioxidant, anti-inflammatory, and antimicrobial properties of garlic and onions (abstract only)

Findings – Both garlic and onions exert their effects on human health via multiple different functions, including antioxidant, anti-inflammatory, and antibacterial properties. The organosulphur compounds in these spices scavenge oxidizing agents, inhibit the oxidation of fatty acids, thereby preventing the formation of pro-inflammatory messengers, and inhibit bacterial growth, via interaction with sulphur-containing enzymes.

Smelling, so inhaling the fumes of onion and garlic is essentially inhaling the volatilized chemical componds, expecially if the scallion or onion is minced and warmed.

That's not very different from the way commercial products like Vicks VapoRub works, as the "Vapor" part is essentially inhaling menthol and camphor fumes, and both have analgesic and anti-inflammatory effects.

Those analgesic and anti-inflammatory properties are going to help with the symptoms of the cold (as Avrohom Yitzchok has said, right now you can't really cure the cause of the cold).

Adding to that, the anti-microbial and anti-bacterial properties may help curing eventual bacterial complications caused by the cold.

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Is there any reason to believe that any species of green onion, also called "scallion", "negi", "spring onion", or a number of other common names, exhibit the same anti-inflammatory and anti-bacterial characteristics as garlic and onions? They lack the developed bulb structure the common onion has, and are eaten for their green stalks instead. – Yamikuronue Dec 12 '12 at 17:06
Furthermore, is there any research to indicate that breathing anti-bacterial or anti-inflammatory substances provides the same effect as consuming them? That second link is hardly scientific proof, it's a claim you appear to be taking at face value without any evidence. Furthermore, the page you linked to indicates that it's the vitamin C content, again without any evidence that vitamin C kills cold virii. – Yamikuronue Dec 12 '12 at 17:09
Thank you, Point taken, seems I left out some passages. What I was trying to say, is that there isn't any research regarding this particular case. But the anti-inflammatory properties are common to all the Allium family, and the smell of onion and garlic is primarily because of chemicals like thiosulfinate, and that's the main anti-inflammatory compound you're inhaling. The second link is not any scientific proof, it was only to say that using onions aganist the cold is common in different cultures. I'll try refining the answer soon. – Duralumin Dec 13 '12 at 8:41

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