Why do we yawn?

Like many of us, you probably think that people yawn when they are hungry or tired. Actually, this is not exactly true! After many studies, all scientists do not explain this phenomena the same way.

A whole family happily yawning together

Yawn to make our brain colder

One of those theories is the one of Dean Falk, an anthropologist. He think that we yawn for make our brain colder. Indeed, when we are tired our brain is warmer than its normal temperature. But as a computer, the brain work better when it is not too warm. When we yawn, air go into us by our nostrils and our mouth, making the blood in our head colder, and so our brain colder. It is also a good way to be more concentrated and attentive.

It has been thought that yawning increased the level of oxygen in the body, but studies have shown that is wrong. Indeed, we do not yawn more when we do sport, whereas it is exactly the moment when our body need more oxygen.

Yawn to be under less stress

It allows to relax face muscles and breath deeply. It is by the way recommended to voluntary yawn through the day, especially when you feel stressed, tired or upset.

Yawn is contagious

Scientists discovered that this phenomena concerns only humans and primates, but when you see someone yawn, you will probably yawn too. Maybe even just by reading this text, you are likely to yawn yourselves. However, some people are less susceptible to contagious yawning than others. It depends on our capability of empathy. The more you demonstrate empathy, the more you are susceptible to contagious yawning.

You can check how susceptible to contagious yawning you are by watching this video!

Did you know?

On average, we yawn around 240 000 time in our lives. We yawn even as fetuses, in our mother's wombs. Moreover, all mammals yawn.