Introduction
The assumption that you can get a cold from cold is traditionally widespread and still holds true today. However, the influence of cold alone cannot cause a cold. If one gets a cold after a stay in a cold environment, a pathogen such as a virus must also be involved. Colds caused by a virus infection occur mainly in the cold months, because the viruses have a better survival in cold air and because the human immune system is weakened by cold and dry air.
Why does a cold give you a cold?
Cold alone is not a direct trigger of a cold. Not every person who is exposed to cold gets a cold and vice versa people also get a cold, although they have not been in the cold before. Therefore a direct connection that only the cold without the presence of pathogens causes a cold cannot be proven.
Rhinoviruses are a common trigger of a cold. These can best survive in cold, wet air. They are therefore supported in their functionality by the cold.
About one fifth of all people have a permanent colonization of the nasal mucosa with these rhinoviruses. With warmth and a functioning immune system, these rhinoviruses are kept in check and no symptoms occur. It is known from research that cold air has an inhibitory effect on the cleansing effect of the nasal mucosa.
The nasal mucosa cleans the air we breathe in and can also eliminate pathogens before they can cause an infection. If the nose is now exposed to the cold, blood circulation is reduced and fewer defense cells reach the mucous membrane to ward off potential pathogens. The nasal mucous membrane is further weakened by the dry air that is typical of the cold.
Drying it out makes it more susceptible to infections with rhinoviruses, for example. Cold is therefore a favoring factor for the causative agents of a cold. Prolonged exposure to the cold can also weaken the immune system.
When it is cold, the entire organism works more slowly and the immune system is also affected. However, this requires intense cold and appropriate clothing can provide good protection against this effect. However, it is not possible to differentiate sufficiently whether the weakening of the immune system is really caused by the cold or whether other factors also play a role.
One of these factors is a vitamin D deficiency, which can be caused by low sunlight in winter. It also leads to a weakening of the immune system. An indirect connection between cold and a cold can be found in that people are more likely to stay indoors during the cold season. Due to poor ventilation and sick people in the vicinity, the cold can spread better and faster. Dry air from heating also plays a role in the susceptibility of the nasal region to infections.
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