Why do people yawn?

Possible causes of yawning include the following: 1. When the inhaled air lacks sufficient oxygen, the brain sends a signal to yawn in order to increase oxygen intake. 2. Yawning can help relax muscles and make it easier to fall asleep. 3. Yawning often occurs when feeling fatigued, helping the body to relax and restore energy. 4. Sometimes, yawning serves as an emotional expression; yawning during periods of irritability or restlessness may help release emotions. If yawning occurs frequently and is accompanied by other symptoms, prompt medical consultation is recommended.