Why do we catch more colds in winter? Above all, can we avoid getting sick?

Cold, the enemy of our immunity

“When it’s cold, our immunity slows down a bit.says Didier Giet. The cold particularly affects the cilia that line our respiratory tracts. These cilia, which act as filters, are less effective at removing microbes when exposed to the cold.” A slowdown that allows viruses responsible for mild viral infections to enter our bodies more easily.

Cold also has a direct impact on the multiplication of viruses themselves. “Viruses, such as the rhinovirus, which causes the majority of colds, multiply better when it’s cold. Conversely, they have difficulty when it’s hot.“.

Another key factor: our winter lifestyle. “In winter, we spend more time in confined, poorly ventilated spaces.” This confinement promotes the transmission of viruses. “When we live in closed environments, we exchange viruses much more easily, whether it’s the cold, the flu or even Covid.” In the summer, our interactions take place outdoors, thus limiting the spread of germs. This is a point that the Covid-19 pandemic has illustrated well.

Can you “catch a cold”?

“Don’t go out with wet hair!” or “Cover yourself up, or you’ll catch a cold!” These are preconceived ideas that are deeply rooted in the collective imagination. However, as Dr. Giet reminds us: “It’s not the cold that gives you a cold, it’s a virus.” So going out with wet hair does not in itself cause a cold.”What is true is that cold can slow down our immunity. But it is the encounter with a virus that makes us sick, not the cold itself.”

Preventing colds

So how do you protect yourself from winter colds? “ Dry air, often caused by heating, dries out our mucous membranes, making them more vulnerable to infections. A humidifier can therefore be a good idea in winter.” Regularly airing out your home is also essential. For the rest, there is no miracle: you need to focus on a healthy diet and restful sleep.Our immunity will be much more efficient if we have a healthy, balanced diet, with fruits and vegetables. It is probably the best medicine! Sleep is also important because it allows the body to find the energy necessary for immunity to start up.”

A cure?

And what about grandmother’s remedies, like inhalations? “These are practices which find a certain justification, since the The warmth and humidity of inhalations can help clear the airways.” In contrast, widely promoted vitamin C supplements have not really proven their worth, he says. “There is no proven benefit to taking large amounts of vitamin supplements to prevent colds. Unless recommended by your doctor, a balanced diet is usually sufficient.”

While vaccination is a valuable weapon against the flu, it remains useless for the common cold. “Unfortunately, there is no vaccine against rhinovirus, as it is a relatively benign virus that mutates a lot. If viruses like rhinovirus or adenovirus did not mutate, we would only catch a cold once in our lives and then we would be fine.”

Finally, in case of a simple cold, there is no need to rush to the doctor. “It is healthy to self-treat minor viral infections, such as colds, and not to carry them to the doctor’s waiting room unless there are warning signs such as a prolonged fever or purulent sputum… You should stay warm and take symptomatic medication.”