system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do we get a sore throat after being in the cold for a while?
gpt
Well it depends on what kind of cold. But often the air is very dry when it is cold, meaning a low humidity. This means it is easier for water to evaporate into the 'dry' air. What you should also know is that water evaporates at all times but the speed at which this happens differ depending on temperature and humidity. Higher humidity meanind lower evaporation and vice versa, and also a higher temperature gives a higher evaporation and vice versa. Now to why you get a sore throat. Your body is around 37C on the inside and every time you breathe out some water from your throat is evaporated and taken with the air, removing it from your throat. Normally this evaporation happens at a speed that your body can keep up with by 'refilling' the water that's lost. However when the air is really dry, like with cold weather, the evaporation happens at a faster speed and your body can't keep up. This results in your throat quite literally drying up and gives you the sore throat feeling.
Also this process happens faster when you breath through your mouth, so to prevent this happening as much as possible try to breathe through your nose. As there is more resistance that way which will recapture some of those water vapors.