LOUISVILLE, Ky. (WAVE) - It's an ongoing myth that cold weather causes the common cold.
While that's not true, the weather does influence how we get a cold.
According to the Centers for Disease Control and Prevention (CDC), an adult in the United States gets an average of two or three colds per year; children have even more.
Rhinoviruses are the most common causes of colds and are responsible for more than half of cold-like illnesses. Rhinoviruses spread through the air as small droplets that are inhaled or by person-to-person contact.
A 2016 study found that a drop in air temperature and humidity over 3 days, in colder climates, preceded rhinovirus infections. This study also found that most infections occurred when the air temperature was below 32°F.
Well, research has found that cold viruses replicate more efficiently in temperatures colder than 98.6° (this is the average human core body temperature). Our nasal cavities are typically around 91.4°, which makes them the perfect location for rhinoviruses to thrive. Researchers have found colder immune cells are less efficient at fighting off viruses. This explains why it is easier for the cold virus to grow and replicate in the comfort of our cooler noses compared to our warm lungs.
Researchers have found that cold weather can impact the immune system, which makes it difficult for the body to fight infections.
Some of those reasons are as follows:
- Vitamin D: Researchers discovered that Vitamin D plays a role in maintaining a healthy immune system. Reduced sun exposure during the winter can lead to lower vitamin D levels.
- Tighter blood vessels: Cold and dry air forces blood vessels in our respiratory tracts to narrow to preserve body heat. This might keep white blood cells from reaching the mucous membrane, which makes it harder to fight off germs.
- More time indoors: More time inside during the winter months may lead to more viruses being spread due to people being in more proximity to one another.
So the cooler temperatures may not be the cause of our sickness, but it can certainly contribute to our body’s ability to fight viruses.