Why Yawn?

Aaaaa... Why do I keep yawning??? I have been yawning a lot today, so I decided to do some research on what a yawn is, what causes people to yawn, and whether or not they are contagious.

A yawn is a reflex usually known to regulate oxygen and carbon dioxide levels in the blood. It is usually involuntary, meaning we can’t control it.

There is no actual proven reason as to why we yawn, but there is a lot of theories or ideas as to why they occur. There are about 3 main theories:

This theory states that yawning happens when our breathing slows down. Less oxygen is being taken in and less carbon dioxide is being released, therefore a yawn will help stimulate both.
Another theory says that we yawn to stretch our lungs and to redistribute a fluid called surfactant that keeps the lungs lubricated inside and stops them from collapsing. This theory therefore, states it is necessary to yawn.
Others believe that it is just a reflex from the brain telling you to relax or someway to moisten your eyes.

This is an interesting tip -
Is Yawning contagious? You may notice that you yawn when others around you are yawning, or even when you think or read of yawning! It is suggested that we yawn when others yawn because our brain naturally mirrors what others in front of you are doing! Isn’t that fascinating?

Hope you’ve learned a little more on yawning. How many times have you yawned while reading this? :p