The Meaning of Yawning - Step To Health

The Meaning of Yawning

Yawning can have multiple causes. Today, we'll bring together 5 of the most common ones supported by the scientific community.
The Meaning of Yawning

Last update: 10 January, 2022

Yawning is often thought to express boredom, inattention, and drowsiness. Although this theory is very popular, scientists actually believe it to be the least likely reason why we yawn. In fact, dozens of theories about the functions of yawning have been proposed so far without enough evidence to consider any of them to be 100% the answer.

In other words, researchers have not found the exact reasons why we yawn. However, they have learned a few things about yawning, so the following article summarizes the most accepted theories. We can promise you two things: the first is that some of them will surprise you, and the second is that before you finish reading this article, you will yawn at least once!

Why do we yawn?

As we’ve already pointed out, scientists still haven’t agreed on the reasons why we yawn. This is partly because the hypotheses put forward have an equal number of points for and against them. Yawning is in itself a mystery – one that we also find in animals.

Indeed, as the evidence shows, most vertebrate species yawn. They do so from the fetal stage (something that also happens in humans) to old age. However, since the theories outlined for humans don’t always apply to animals, some experts suggest that yawning has multifactorial implications in different species.

Because of this, there’s no single reason why yawning exists. Animals and humans yawn for different reasons, so the action may be motivated by other elements at the same time. With this in mind, here are some of the most interesting hypotheses.

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1. We yawn because of stress and fatigue

El bostezo y el estrés
According to some scientific studies, the origin of yawning could be related to stressful situations and cortisol levels.

A study published in 2011 in the journal Medical Hypotheses pointed out that we yawn due to increased cortisol levels in our bodies. Cortisol is a hormone produced in the adrenal gland when we’re stressed and fatigued. So, this would explain why we tend to yawn in these contexts.

Although there’s no strong evidence that yawning helps control cortisol levels, it’s thought to be a kind of alert to take appropriate action. In small doses, cortisol is healthy, but it can cause heart problems, sleep disorders, and impair the immune system when out of control.

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2. It’s a natural way for the body to cool the brain

Another of the best-known hypotheses why we yawn is that it has a thermoregulatory function on the brain. In fact, animal studies and research have been done that support this theory. It appears that the frequency of yawning increases as the temperature is higher, and this helps to reduce the temperature in the vicinity of the brain significantly.

Evidence indicates that this also plays out in humans. A study published in 2007 in Evolutionary Psychology tested the frequency of yawning while participants held hot and cold compresses to their foreheads. In the second case, the action was much more frequent, which gives us supporting clues for this hypothesis.

3. Yawning helps relieve ear discomfort

Also, yawning is thought to help alleviate hearing problems experienced during changes in altitude (flying in an airplane or using an elevator, for example). Theoretically, this would be achieved by the opening of the eustachian tubes that are generated following a contraction of the tensor tympani muscles when yawning.

Studies have supported this hypothesis, so it’s one of the reasons why yawning frequency increases during rapid changes in altitude. It may also have implications for sharpening auditory sensitivity or alleviating any discomfort felt throughout the auditory sensory plane.

4. We yawn because of boredom

El aburrimiento y los bostezos
The clearest association made with yawning is that of boredom and monotony. While this is true in some cases, it’s not the only explanation.

Experts have found several physiological changes before, during, and after yawning. It’s known that just after yawning, the heart rate increases, the eye muscles tense, and lung capacity is enhanced. The sum of all this produces general arousal in the body.

What is the reason for this arousal, and what is its function?

Well, some researchers have theorized, in line with popular belief, that boredom may be the reason. Indeed, we yawn in contexts where our attention or interaction is minimal (watching TV, for example), so this reaction could help motivate us to stay awake or enhance our attention.

5. We yawn to promote social interaction

It is well known that yawning is contagious. This has led some experts to claim that yawning has an empathic mechanism with pro-social consequences. The levels of empathy may even be higher than those achieved during laughter interaction.

Therefore, this mechanism may have evolved as a tool to promote teamwork, otherness, group bonding, and as a method of social insertion. The social aspect of yawning is by far the most intriguing possible theory to scientists.

Of course, there are dozens of other theories as to why we yawn. These five are the most reputable – at least considering the current research landscape. Remember that there may be many causes, so you don’t yawn for just one specific reason.

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Why Are Yawns Contagious?
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Why Are Yawns Contagious?

Why are yawns contagious? Almost two thirds of people are sensitive to the contagion of yawning which means they'll yawn too!

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