Yawning is a mostly involuntary process of opening the mouth and breathing in deeply, filling the lungs with air. It's a very natural response to being tired. In fact, yawning is usually triggered by sleepiness or fatigue. Some yawns are short, and some last for several seconds before an open-mouthed exhale.

Is yawning good or bad?

Yawning is a normal response by the body to drowsiness or fatigue. Yawning may also be triggered by observing someone else yawning. Yawning excessively may mean taking in this deep breath more often, generally more than a few times per minute.

Is yawning caused by low oxygen?

In addition, different regions of the brain control yawning and breathing. Still, low oxygen levels in the paraventricular nucleus (PVN) of the hypothalamus of the brain can induce yawning. Another hypothesis is that we yawn because we are tired or bored.