The reasons for yawning, people yawn from the day they are born until the end of their lives, why do people yawn? Possible odds are: a. A yawn lasts for about 6 seconds, during which time the person closes his eyes and recuperates, and the whole body’s nerve muscles get completely relaxed, so it can be considered that yawning is the best way to make people get the best rest physically and psychologically, and has an important physiological protective effect on the body. Second, some people believe that yawning is a manifestation of cerebral hypoxia, the human body through the deep breathing exercise of yawning, so that the blood increased oxygen, discharge more carbon dioxide, thus making people more energetic. When people are sleepy, they tend to yawn constantly to remind the body that the brain is fatigued and needs to sleep and rest, so yawning is also a method of hypnosis. When people are about to enter into intense work before, they also yawn, which may be the human body with the help of deep breathing to increase more oxygen in the blood and improve the activity of the brain. The above is for reference only, please refer to the doctor’s face-to-face guidance for specific medication and treatment.