3 doctors weighed in:
Why do people yawn? I heard yawning is a sign that your brain isn't getting enough oxygen. Is this true?
3 doctors weighed in

Dr. Kenneth Cheng
Family Medicine
1 doctor agrees
In brief: True
Yawning is a sign of tiredness.
Additionally, when your carbon dioxide (the gas given off with exhaling) level starts to rise in your body, it does stimulate the brain to cause you to yawn. The theory is that the yawning will cause you to take a deep breath and inhale more oxygen and exhale the excess carbon dioxide.

In brief: True
Yawning is a sign of tiredness.
Additionally, when your carbon dioxide (the gas given off with exhaling) level starts to rise in your body, it does stimulate the brain to cause you to yawn. The theory is that the yawning will cause you to take a deep breath and inhale more oxygen and exhale the excess carbon dioxide.
Dr. Kenneth Cheng
Dr. Kenneth Cheng
Thank
Dr. Eric Toloza
Surgery - Thoracic
In brief: Perhaps
Similar to sighing, yawning is a reflex to re-expand your lungs, which may have some of their air sacs not fully expanded due to periods of shallow breathing .
..

In brief: Perhaps
Similar to sighing, yawning is a reflex to re-expand your lungs, which may have some of their air sacs not fully expanded due to periods of shallow breathing .
..
Dr. Eric Toloza
Dr. Eric Toloza
Thank
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