Does onions absorb influenza from the air? Scientists decide it

The pioneers of social networking sites are circulating extensive publications about the ability of onions to absorb the influenza virus from the air, among its many benefits.

These publications recommend placing chopped onions in the rooms of the house to prevent influenza infection. One of the publications also narrates a story that claims that it happened in 1918 during the spread of the Spanish flu, in which it stated that a family survived the flu that killed tens of millions because the head of the family put onions around the house, and when the doctor examined the onions under the microscope, he found that it contained influenza and other diseases. bacteria.

Does onions prevent influenza? There is no doubt that these publications are not based on any scientific background, as they did not distinguish between bacteria and viruses. The talk that onions absorb influenza from the air are just myths that have no scientific basis.

On the one hand, influenza is a viral infection caused by one of the influenza viruses, not a bacterial infection. Influenza is spread by droplets containing viruses in the air between people who are close to each other, and it can also be spread through contaminated hands with the virus.

Recently, many misleading news spread about onions, which prompted several websites to publish denials of them based on expert opinions.

Politifact cited an article published in 2017 by Joe Schwarz, director of the Department of Science and Society at McGill University, in which he denied that onions are a magnet for germs, based on clear scientific evidence.

“Onions are not considered an incubator environment for germs, but rather the opposite, as onions contain sulfur compounds that usually fight germs, meaning they do not absorb them,” Schwarz said.

“Cutting onions releases enzymes behind a chemical reaction that generates propanesulfonic acid, which in turn breaks down to produce sulfuric acid. It is sulfuric acid that causes tears when cutting onions. It inhibits the growth of bacteria,” Schwarz said.

In his article, Schwarz also explained that “when cutting onions, their surface dries directly, reducing the moisture that bacteria need for growth. The growth of bacteria also needs a source. For example, onions may become contaminated from surfaces or dirty hands, but not from bacteria in the air.”

In turn, nutritionist Chantal Hanna told AFP, “Vegetables and fruits are somewhat safe and are not an incubating environment for bacteria unless they are exposed to polluting factors from their source, such as irrigation with contaminated water and not being washed well before consumption, or if they are cut on the same cutting board and consumed without cooking them on High temperature”.

According to Hanna, “the foods that may constitute a favorable environment for the growth of germs are those that contain a high percentage of proteins, such as all kinds of meat and cheese eggs…”, and this is not the case with onions.

In the same context, misleading publications also went on to say that eating onions becomes toxic and causes intestinal diseases due to its absorption of bacteria. But this claim is also wrong and has no scientific basis.

“I am not aware of any case of poisoning caused by the onion itself, and I have never heard of such cases in the French Dietetic Association (…) It seems very unlikely to me,” Xavier Comol, professor of biochemistry and toxicology at the University of Paris, told AFP.

As for the professor of pharmacology at the University of Paris, Sylvie Michel, she gave a definitive answer by saying that she had done research and “there is no scientific evidence to prove that onions become poisonous after cutting.”

“There is no specific type of bacteria” that hits the chopped onions, she said, adding that like other people, she often leaves the chopped onions for food the next day.

On the other hand, the American Onion Producers, Traders, and Distributors Association published a statement on the matter and ranked claims about the toxicity of onions after cutting them at the forefront of “common myths” about vegetables and fruits.

The association said, “Proper handling of onions does not make them toxic, and they can be kept in the refrigerator in a pressure vessel for up to seven days.”