It’s winter time and for most of us that means having to put up with a pesky runny nose. Although we tend to put it down as just another seasonal problem along with freezing cold whether and gloomy, dark evenings, there is actually a scientific reason behind having to carry tissues around with you when the temperature drops.
There are two basic reasons why your nose runs double time when the weather is chilly. Firstly, your runny nose is actually protecting your lungs. Think of your nose as a humidifier for your lungs. Your nose breathes in somewhere between eighteen to twenty thousand liters of air each day. Your nasal passages regulate this air by warming and adding moisture to it, making it safer for you to breathe it into your lungs. Extreme cold and dry air can even cause cracks and swelling in the lungs, so your nasal humidifier is helping to make your lungs and bronchial tubes more comfortable, warding off any irritation to their linings. To do this job, the moist tissues inside your nose need to increase fluid production. But sometimes too much fluid can be produced, so the excess drips out, causing a runny nose.
To protect yourself from that brisk winter air and to help combat that drippy nose, wrap your neck with a scarf and bring it up to cover your mouth and nose. This will help warm the air you are breathing as well as keeping it moist with condensation from your mouth breath.
Besides this respiratory biology, there is also some basic thermodynamic physics going on when your nose runs from breathing in cold air. Runny nose reason number two is all down to the warm air coming out of your nose when you breathe out mixing with the cold air outside. Just as a cold front meeting a warm front creates condensation in the clouds causing it to rain, when your warm breath meets the cold winter air, it forms condensation. This condensation accumulates inside your nostrils and they inevitably begin to drip.
So, no matter how healthy you are, the science behind a runny winter nose shows that you can’t escape a runny nose in the winter! The best way to face it is to keep your nose and mouth covered as much as you can when you brave the bleak weather and always keep a tissue handy!