Dr. Dean

Why Do I Yawn Even When I'm Not Tired?

Posting Date: 03/31/2000

Lori: Even when I've had a good night's sleep and I'm not tired, I find myself yawning a lot in meetings and at church. Why is that?

Dr. Dean: Meetings are often very unexciting, with church running a close second. It's normal to find them "yawnable."

Visit the Sleep Disorders Center

People have a common misconception that the urge to yawn is triggered by the body's need for more oxygen. Well, according to a doctor who has made the study of yawning his life's work, the yawn is a communiqué.

It warns you that your body has slowed down and that sleepiness might overtake you. The warning is a reminder to prepare to bed down if it's nighttime and you're at home, or to perk up if it's broad daylight and you're in front of your boss or the preacher.

The yawn also communicates impending sleepy time to a group. For example, primates signal each other through yawns that evening time is coming on and they should seek shelter. We human animals too have all experienced being in a room with a yawner whose yawn infects everyone in the room.

A yawn can even be communicated by the eyes alone. Researchers have covered a person's mouth, leaving just the eyes showing, and the invisible yawn will set off yawns among a group of spectators. So a yawn is not communicated by mouth alone.

There is a type of very rare brain tumor and a neurological illness that can cause excessive yawning, but it's very unlikely that you have anything like that.

Maybe sitting in the first row at church will perk you up.