Finally, researchers have found an answer to why runny noses and the flu occur more often during the winter months.
The reason is physiological. This is demonstrated by an American study published on Journal of Allergy and Clinical Immunology.
“Traditionally, cold and flu season was thought to occur in the colder months because people are indoors more, where airborne viruses can spread more easily,” said Benjamin Bleier of Harvard University. , one of the authors of the study.
“However, our study points to a biological root cause,” he continues.
A fierce battle is fought in the nose
According to the study results, we are at higher risk of respiratory infections such as flu, colds and corona when the temperature drops.
The reason for this can be found in the nose. This is where our body’s first line of defense against invading pathogens that cause disease is found.
When our line of defense in the nose is functioning optimally, a swarm of so-called extracellular vesicles is released, the purpose of which is to capture and attack invading organisms that can make us ill.
But when the nose gets cold, its defenses against external pathogens like viruses and bacteria also deteriorate, the study shows.
More specifically, the researchers exposed study participants to temperatures of 4.4 degrees for 15 minutes. This resulted in a five degree drop in temperature inside the nose.
According to the researchers, the consequence of the drop in temperature was that the participants had a worse immune response in the nose.
The number of the so-called extracellular vesicles, which have the task of defending the nose from disease, thus decreased by almost 42 percent with cold temperatures, while the remaining ones, which were released into the nasal cavity, functioned worse than at warmer temperatures. elevated.
In other words, the riddle of frequent winter ailments is solved.
The question now remains of how best to protect the exposed nose, which, with its protruding position in the center of the face, is particularly exposed to both cold winds and bacteria.
