This article explains the theories and reasons behind yawning and why it can be contagious.
However, when experts measure blood oxygen and carbon dioxide, they find little correlation with yawning.
Yawning increases lung capacity and improves blood flow to the heart, benefiting respiration.
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Researchers also believe yawning repositions muscles to widen the airway, increasing oxygen in organs and tissues.
Arousal
Some believe yawning is anarousaldefense reflex occurring when people are bored or sleepy.
Body Temperature
Researchers have proposed that yawning cools the brain.
Research has also found that yawning is associated with outdoor air temperature.
Why Do We Yawn After Seeing Someone Else Yawn?
Have you ever seen someone yawn and suddenly have the urge to yawn?
Contagious yawns have been observed in humans, other mammals, and some birds.
As a result, you may yawn for different reasons.
Researchers believe this could increase heart rate and stimulate hormone release.
People yawn when they’re tired because yawning promotes arousal and activates the brain.
Similarly, when you first wake up, yawning has the same effect.
Summary
There are several theories as to why people yawn.
Healthy sleep habits are an excellent place to start, but see a healthcare provider if it continues.
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