We all have fond memories of being told we'll 'catch a chill', or worse, if we go outside without a coat, but can you actually catch an illness from the cold?
We all associate winter with colds and the flu, and that is for good reason. But it's not actually the lower temperatures that directly cause an illness. While people do tend to catch viruses leading to a cold more often in winter, it is largely to do with the effect the weather has on our behavior, rather than the weather itself.
When the temperature drops and snow or rain arrives, we are more likely to spend time indoors with others, increasing the risk of infection.
Cold weather may also reduce our first line of defense - our nostrils. Viruses often get trapped in the mucus inside our noses, with the tiny hairs.
These tiny hairs, called cilia, work to prevent viruses penetrating any deeper. However cold weather can make cilia less efficient, and they actually stop 'beating' entirely below 39.2 F.
Additionally, when you are cold, especially in your nose, blood vessels constrict, reducing the ability of white blood cells from our immune system to wipe out viruses. So while you can't catch a chill, the cold weather does indirectly make catching an illness more likely.