Why do we catch colds more easily in winter? Scientists finally know why!

At the risk of being accused of raking up old controversies, I would like to once again draw attention to the phenomenon of wearing face masks.

As it happens, two different points of view recently crossed my paths once again with regards to the pros and cons of wearing face masks when you want to protect yourself against a virus. Ardent proponents continue to express the government's position that face masks are useful in preventing infections.

Rereading thos pros and cons more or less coincided with rereading the first book "Gifbeker" by Jan B. Hommel (a pseudonym) with a collection of columns he wrote during the pandemic. These columns can also be consulted online for free.

The column I am specifically talking about has the title "#mondkappennou" a combination of the word 'mondkap' (face mask) and the expression 'kappen nou' (stop it). As a neurologist, it was very difficult for him to diagnose patients , who wore a face mask, because so much of the facial expressions can no longer be observed, from which a lot can be read. He explains this in his blog.

These personal considerations are of course only a fairly small individual matter. The more important question in regards to the general public who are either forcefully or voluntarily wearing facemasks is how useful face masks actually are.


Let us first note that until recently in the Western world, face masks were worn almost exclusively by medical professionals such as dentists and surgeons when they come into close contact with patients and mainly serve to prevent that splashes from the patient end up on the professionals face.

In terms of protection against a coronavirus such as SARS-Cov2, a face mask had no added value. At least, that was until (non-medical!) face masks were suddenly made mandatory. Before they became mandatory, mr Van Dissel (head of the National Health Institute RIVM) stated they are ineffective.
After all, the pores of a face mask are an order of magnitude larger than a virus. A virus is so incredibly small that it can only be observed with electron microscopes. Therefore, the comparison is often made of chicken wire through which mosquitoes can fly easily.

Only recently it became apparent the Ministry of Health actually knew and acknowledged how useless non-medical face masks were, but that the requirement by the general public to wear non-medical face masks was very consciously used to influence people to change behavior (nudging).
Moreover, this way it was more easily possible to single out contrarian thinkers who refused to participate in this circus and make them the targets of ridicule and harassment by obliging mask wearers or public servants.

During the period when face masks were made mandatory, I was usually willing to wear them, even though I personally found it extremely annoying because it became very difficult to understand someone well, since as a hearing-impaired person I partially rely on lipreading to understand what people say.
My partner was a lot more rebellious, partly because he wears glasses and was bothered by the warm air that escaped around the edges of a non-working face mask caused the glasses to fog up.

In short, we have all been deceived and become victims of a great behavioral experiment, haven't we?

Imagine my surprise when DrBeen (Mobeen Syed), a medical doctor who is highly respected by critical thinkers, reported an interesting new finding, which allows no other conclusion than to establish that wearing a mask wasn't entirely useless in preventing viruses to enter your body, even though they can easily slip through the pores of a mask!

How is that even possible? Of course not by actually stopping the virus with the mask itself, but because the nose, which is the very first line of defense against viruses and bacteria, can do its job better when you are wearing a face mask or scarf! At least, it can make a difference when you are in a cold environment.
In this video, DrBeen explains the findings of a study by researchers from Egypt and Harvard University, who have finally discovered why we are more susceptible to the flu and colds when the weather turns cold.


Listen and watch for yourself: Groundbreaking Study Shows Why Is Our Immune System Knocked-out In Winter?

While extremely insightful, drBeen's explanation is also fairly technical , it may be easier to read the article below by CNN which consulted various rhinologists , among which Benjamin Bleier who conducted part of the research.

Scientists finally know why people get more colds and flu in winter

A chill is in the air, and you all know what that means — it’s time for cold and flu season, when it seems everyone you know is suddenly sneezing, sniffling or worse. It’s almost as if those pesky cold and flu germs whirl in with the first blast of winter weather.

Yet germs are present year-round — just think back to your last summer cold. So why do people get more colds, flu and now Covid-19 when it’s chilly outside?

In what researchers are calling a scientific breakthrough, scientists behind a new study may have found the biological reason we get more respiratory illnesses in winter. It turns out the cold air itself damages the immune response occurring in the nose.

“This is the first time that we have a biologic, molecular explanation regarding one factor of our innate immune response that appears to be limited by colder temperatures.”
In fact, reducing the temperature inside the nose by as little as 5°C kills nearly 50% of the billions of virus and bacteria-fighting cells in the nostrils, according to the study which was published early December 2022 in The Journal of Allergy and Clinical Immunology.

“Cold air is associated with increased viral infection because you’ve essentially lost half of your immunity just by that small drop in temperature”
“it’s important to remember that these are in vitro studies, meaning that although it is using human tissue in the lab to study this immune response, it is not a study being carried out inside someone’s actual nose. Often the findings of in vitro studies are confirmed in vivo, but not always.”

A hornet’s nest

To understand why this occurs, Bleier and his team and coauthor Mansoor Amiji, who chairs the department of pharmaceutical sciences at Northeastern University in Boston, went on a scientific detective hunt.

A respiratory virus or bacteria invades the nose, the main point of entry into the body. Immediately, the front of the nose detects the germ, well before the back of the nose is aware of the intruder, the team discovered.

At that point, cells lining the nose immediately begin creating billions of simple copies of themselves called extracellular vesicles, or EV’s.

“EV’s can’t divide like cells can, but they are like little mini versions of cells specifically designed to go and kill these viruses. EV’s act as decoys, so now when you inhale a virus, the virus sticks to these decoys instead of sticking to the cells.”

Those “Mini Me’s” are then expelled by the cells into nasal mucus (yes, snot), where they stop invading germs before they can get to their destinations and multiply.

“This is one of, if not the only part of the immune system that leaves your body to go fight the bacteria and viruses before they actually get into your body.Once created and dispersed out into nasal secretions, the billions of EV’s then start to swarm the marauding germs. It’s like if you kick a hornet’s nest, what happens? You might see a few hornets flying around, but when you kick it, all of them all fly out of the nest to attack before that animal can get into the nest itself. That’s the way the body mops up these inhaled viruses so they can never get into the cell in the first place.

A big increase in immune power

When under attack, the nose increases production of extracellular vesicles by 160%, the study found. There were additional differences: EV’s had many more receptors on their surface than original cells, thus boosting the virus-stopping ability of the billions of extracellular vesicles in the nose.

“Just imagine receptors as little arms that are sticking out, trying to grab on to the viral particles as you breathe them in. And we found each vesicle has up to 20 times more receptors on the surface, making them super sticky.”

Cells in the body also contain a viral killer called micro RNA, which attack invading germs. Yet EVs in the nose contained 13 times micro RNA sequences than normal cells, the study found.

So the nose comes to battle armed with some extra superpowers. But what happens to those advantages when cold weather hits?

To find out, Bleier and his team exposed four study participants to 15 minutes of 4.4°C , and then measured conditions inside their nasal cavities.

“What we found is that when you’re exposed to cold air, the temperature in your nose can drop by as much as 5°C. And that’s enough to essentially knock out all three of those immune advantages that the nose has. In fact, that little bit of coldness in the tip of the nose was enough to take nearly 42% of the extracellular vesicles out of the fight.
Similarly, you have almost half the amount of those killer micro RNA’s inside each vesicle, and you can have up to a 70% drop in the number of receptors on each vesicle, making them much less sticky.
What does that do to your ability to fight off colds, flu and Covid-19? It cuts your immune system’s ability to fight off respiratory infections by half.”

You don’t have to wear a nose sock

“As it turns out, the pandemic gave us exactly what we need to help fight off chilly air and keep our immunity high.
Not only do masks protect you from the direct inhalation of viruses, but it’s also like wearing a sweater on your nose,”

“The warmer you can keep the intranasal environment, the better this innate immune defense mechanism will be able to work. Maybe yet another reason to wear masks!”
In the future, Bleier expects to see the development of topical nasal medications that build upon this scientific revelation. These new pharmaceuticals will “essentially fool the nose into thinking it has just seen a virus. By having that exposure, you’ll have all these extra hornets flying around in your mucous protecting you.”

Our comment

Of course, masks don't really protect against inhalation of virsuses, unless you are wearing a proper air-tight medical mask, but they do slightly warm up your nose and therefore increase your immunity levels! Better yet to simply wear something more comfortable like a shawl, that is designed to keep your face warm!