Why is it that if you sleep with cold air blowing on you at night you wake up with a cold or a sore throat?

Because the moving air causes water to evaporate from your nose, throat, eyes, etc. more quickly while you sleep. Usually (as in, awake) you compensate for this by blinking more, swallowing more, etc. But you are unconscious, so you don't do these things. Your eyes may stay partially open without moving for long periods of time drying them out. Likewise, your throat dries out due to not swallowing, which is worsened by increased drying effect caused by breathing the the moving, drier air. (In a still air situation, you humidify the air near you by exhaling.) The moving air pushes this humidity away and the dry air moves through your respiratory system all night. The skin/membranes in your nasal cavity and throat become brittle as the mucus lining them dries and hardens.

Upon waking up you will inevitably move or pull the skin in these dried areas by swallowing or snorting, and the dry membranes will crack. Once the skin breaks it becomes irritated, and there's your sore throat. This soreness will persist until the torn membranes rehydrate and heal (hours to sometimes days). The dry itchy eyes usually repair/rehydrate themselves in a matter of minutes. The extent to which the damage occurs depends on what position you were sleeping in, and at what point in the night, which is why some days you wake up worse than others.

One way it can be good because the cool air kills those little bugs that give us allergies. Though your immune system can be suppressed if the bodies temperture drops too low therefore leaving you exposed to sore throats and the like.. Make sure that you are warm in bed and you should be okay .. I also use a fan and its not such a bad thing because it does help you sleep by dropping the temperture of your brain.. Are u just useing the fan or do you leave the window open ?? You could be sleeping with your mouth open and its drying out your throat. Is your nasal passage blocked at night ?? if so get something for it.

Colds are not caused by cold air, that is absurd.

However, you could have a sore throat just from dehydration caused by any air blowing over you, hot or cold.

You will never get a cold unless germs are present. Cold air or water might make you uncomfortable but you won't get sick unless you get infected by germs.

NOT me I like my body warm but I need .cool air to breath You will only get a cold if your immune system is already down.

I have same problem. Do u use ceiling fan or table fan? if u use ceiling fan turn the speed low. If use table or stand fan make sure it doesn't blow direct to ur face. Turn ur face away from direct blow or u may want to cover face with blanket or something else. It works for me. Good luck.

The same thing happens to my boyfriend and it bothers me a lot...because He wakes up all moody complaining about his nose and throat..

I not sure but maybe it has something to do with the pores on your body being open.

It can make you sick. It can also give you Bells Pusey.