Thus, contrary to our impression that yawning is rude and insulting, Dr. Gallup asserts that “yawning is really a compliment, because it suggests that brain mechanisms have kicked in to reinstate and optimize mental processing.”

Yawning is mostly involuntary, meaning you don't have control over it. And most scientists consider it a reflex. However, you can make yourself yawn by breathing in gradually while retracting the tip of your tongue and opening your jaw repetitively. In addition, seeing other people yawning often triggers one.

One is that when we are bored or tired, we just don't breathe as deeply as we usually do. As this theory goes, our bodies take in less oxygen because our breathing has slowed. Therefore, yawning helps us bring more oxygen into the blood and move more carbon dioxide out of the blood.