Why is only half my nose working, when we get a cold or hay-fever? Why does the side you can breathe from continuously switch?
8 out of 10 people experience this and it’s one of the most frustrating parts of having a blocked nose. It turns out your nostrils are trading breathing duty all the time, we just aren’t noticing it until our noses are blocked and there is an obstruction to the airflow. for these people, the trade is due to a swelling in one nostril that swaps nostril every few hours.
This is all to benefit your sense of smell. Your nostrils exist as a pair because making one work while the other rests helps to keep the nasal passages healthy. Inside the nasal passage the nose is lined with cilia, which are the little hairs responsible for blocking and removing nasty substances like dust and mucous from damaging the respiratory tract. These need to rest every once in a while to prevent them from drying out and restricting the air flow through one nostril at a time gives them this chance.
By allowing the cilia to rest, the nose also has a better sense of smell. Some chemicals in the air will bond to cilia well and some will not, by increasing the speed at which they enter the nasal passage, there is better chance of the cilia at the back catching them and detecting the smell. The speed is increased by having this nasal cycle of one nostril working at a time.
Though irritating, having this cycle benefits the advancement of mankind so be grateful for it next time you have a cold.