Why Do We Yawn?

Why Do We Yawn? 2

There are many things that trigger yawn. People yawn when they wake from a deep sleep, and when they are tired. People also yawn when they are bored, hungry, anxious, or about to begin a fresh activity.

It is interesting to note that some people who skydive yawn right before jumping.

Some police officers even say they tend to yawn while entering a tense situation. People tend to yawn when they see other persons yawning, as well. However, the physiological purpose of such an act is still unknown. 

Why Do We Yawn?

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Yawning Facts

It is a known fact that yawning is transferable in humans. You tend to yawn whenever you notice someone next to you does this act. A study conducted in 2017 shows that the primary reflexes in the motor cortex of the brain are responsible for yawning.

The study also shows that people have limited ability to resist yawning when somebody near them yawns.

Yawning can be transmissible between humans and pet dogs. Most surprisingly, a dog tends to yawn as soon as he hears his owner yawn. Yawning is tied to social interaction and empathy.

Hence, it underlines the fact that humans have a close connection with this domesticated companion species for a long time. 

Yawns last for about 6 seconds. On average, it has been noticed that women have a shorter duration of a yawn as compared to men. During the 6 seconds, your heartbeat can raise by 30% than normal.

Another interesting fact about yawning is that it helps to calm down an agitated brain. A cool brain helps you to have a better understanding of the present situation.

When you begin to yawn, the powerful stretch of your jaw increases the flow of blood in the head, face, and neck. The deep breath while yawning forces the blood from your brain and spinal fluid downwards. The cool air makes these fluids cool.

The whole process works like a radiator. 

What are the causes of yawning?

Yawning is a great example of fatigue, which indicates that you are ready to sleep. But it may necessarily not be a symptom that you are exhaust. Here are some other potential causes.

It is contagious

When you see or think about yawning, you do it yourself. It is an involuntary imitation that relates to the evolution of yawning. It indicates that it’s time to relax.

Over time, this trait has been selected because it helps people to accept a changing environment such as the absence of a menace or darkness. The reason is more social rather than a biological one. 

You are bored 

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Young bored man on couch using TV remote control zapping for another movie or show late at night. Looking disinterested and sleepless. In entertainment People insomnia and Sedentary lifestyle concept.

When the temperature of your brain rises, you tend to yawn. A hot brain signals your body to open the mouth and breathe deep. It helps to flex the walls of the sinus cavity and cools the other important organs. 

You are about to move 

 Yawning is linked with some actions in your body such as joint movement, increased heartbeat, and muscle stretching, it acts like a part of your body, which is preparing itself for an activity. 

What happens when you yawn?

The answer to this question of what happens when you yawn is straightforward. Your mouth wide opens, and you inhale the deep fresh air, and end with a brief exhalation. At this time, your skull muscles contract and expands while you take in air. 

New and cool blood is pushed towards your skull and warmer blood is pushed downward. Secondary behavior like pushing your head back or stretching your arms wide apart acts as cooling techniques when ambient air hits your underarms. 

The full-body stretch prepares your muscles for the quick action and contributes to pushing yourself towards alertness that results because of a cool brain.

It has also been found in many studies that brain temperature rises right before yawns and the brain cools down soon after a yawn. 

Researchers have found that frequent yawns are because of high brain temperatures. Brain thermoregulation is an important element as far as the study for the evolution of humans exists.

But the hypothesis for thermoregulation explains only the root cause, which is spontaneous yawning. 

Most of the research is done on spontaneous yawning. It is an occurrence in which you tend to yawn while watching other people yawn. It may also arise when you think, or someone mentions about the action. 

Is yawning a sign of lack of oxygen to the brain?

It is not understood the exact reason for yawning. This action may not be the only sign of tiredness, but it may be the changing conditions within the body that causes yawning.

Several studies show that people yawn when they are experiencing fatigue and when they are awake. 

This action may be triggered sometimes when the alertness seems to change. However, it is understandable that the action is contagious. There are plenty of theories that have been presented over several years regarding the occurrence of yawning. 

For several years and after many types of research, it was thought this action brings in more air to the body. The probable reason is the low oxygen levels that were sensed in the lungs.

But after a few studies, it became clear that the lungs do not sense decreasing oxygen levels in a normal way.

Moreover, fetuses tend to yawn in the uterus, yet their lungs are not ventilated. In addition to that, the different regions of the brain use to control breathing and yawning.

Still, low levels of oxygen in PVN (paraventricular nucleus) present in the hypothalamus of your brain can influence yawning. Hence it is seen that the popular theory about yawning may not be true. 

Why do we yawn when we are tired?

When you feel tired, your brain cells are deprived of the requisite amount of oxygen. When you feel drowsy, bored, sleepy, or tired, you breathe slowly and end up taking less oxygen. Hence, you open your mouth wide and take oxygen to fulfill your needs for breathing. 

One of the most popular hypotheses about yawning is that it occurs when a person becomes too tired or bored. This action is considered an involuntary process, where the mouth opens wide and breathes in oxygen deeply. It fills the lungs with sufficient air. 

Yawning is a very natural process in response to tiredness. In fact, yawning gets triggered because of fatigue and sleepiness. It occurs when you talk or think about it. It may even start when you see someone doing it. 

When the body gets tired, the energy levels become significantly low. This means the body will need more oxygen to perform well in all the activities. When you yawn, your body will receive more air. As such, the body cells will receive more oxygen. 

With sufficient air in place, your body can keep going until your next sleep. Yawning is considered as a sign from your body to take rest or indulge in a deep sleep. You may have noticed that you tend to yawn for some time, and it vanishes for a while.

It comes back after a few moments. This way, your body keeps the oxygen supplemented through yawning.

How do I stop yawning so much?

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yawing handsome man manager sitting at working place in office looking tired at the end of day. multitasking, work concept.

Researchers are not sure why people yawn. It tends to occur when we are stressed or tired. However, there are certain ways to suppress whenever you feel to have such a moment. 

Breathe through nose 

Some studies highlight that people yawns because of the lack of oxygen. Hence, taking a few deep breaths when you sense a yawn coming, can help you to stop it before it arrives.

You should take in fresh air through your nose and release out the air through your mouth. When you breathe, try to pull the air in your stomach and lower abdomen instead of your chest.

Take a cool beverage 

A cool body can be helpful in suppressing a yawn. When you feel that it may come in a while, try to have a cold drink. You can drink cool juice, ice water, or iced coffee or tea. Carbonated beverages can stop it, but they will give rise to gas or another discomfort. 

When you are attending a class, meeting, or some other activity where this act would be rude, you can bring a drink with you if allowed to. A bottle of cold water close to your hand can save you from having a yawn if it happens to come.

Eat chilled foods 

Quite similar to the cold drinks, chilled foods can help you in preventing a yawn. Eat cold foods such as refrigerated veggies, fruits, yogurts, and cheese. Avoid foods rich in sugar like ice-cream, because will have a reverse effect.

Sugar will make you feel tired. As such, there could be more yawns. Make a selection of healthy foods when it is about eating chilled foods.

Use cold compress 

When food and water aren’t giving you the desired result, make use of a cool compress. Take a clean towel or cloth and run it with cool water. Place it on your head. Within moments you will begin to yawn less.

Why do your eyes water when you yawn?

When you notice someone yawn, you may do. But something else happens. You may shed a tear or a few more after repeated yawns. However, it is not a sign that you need a quick nap. When you yawn, the muscles surrounding your eyes begin to pull tight. 

This puts pressure on the lacrimal glands. These glands are tucked away deep under the upper eyelids below your eyebrow bones. The glands produce the watery element to your eye’s natural tears.

They are responsible for producing and releasing tears in small amounts throughout the day. 

They cover the surface of your eyes all the time. The tears don’t come only when you cry but they are present all the time and that makes your eyes look glossy. When you yawn, the facial muscles begin to tighten. The lacrimal glands are squeezed and as such, a small amount of tear appears.

The next time when you are about to yawn, pay close attention to the facial muscles surrounding your eyes. You will notice that they tend to become hard and then you will have a watery eye. It isn’t sad, but it’s all about science. 

Is yawning good for you?

It is very difficult to say if yawning is a good thing or a bad one. It is nothing but a physiological response that scientists really don’t understand. Recent research studies show that it increases the flow of blood to the jaw and aids in cooling the brain.

The claim is based on brain temperature when yawn begins. It is natural to yawn more in summer than in winter. For a quite long time, researchers held the belief that the body tends to yawn because it requires a fast influx of oxygen. 

This theory was later debunked after several studies, which shows no increase in the amount of oxygen post yawn. Yawning helps you to regulate brain temperature. But, a lot of research has to be done for attaining the right conclusion. 

As a bodily function, yawning is good for you because it brings in fresh air to the body. This fresh oxygen is good for the throat and lungs to reduce fatigue. As it is contagious, you need to be careful while doing this in public because it is considered vulgar, sometimes.

Can you yawn too much?

A person can yawn too much. It is called excessive yawning where it occurs more than once within a minute. Although excessive yawning usually results from being bored or sleepy, it can be a sign of an underlying medical problem. 

Excessive yawning is the result of a vasovagal reaction. During this period, the vague nerve has increased activity. The nerve runs down from the brain through the throat and to the abdomen. The blood pressure and heart rate drop rapidly. This is because of the activeness of this nerve. 

The exact reason for such a situation is unknown. It can occur because of the following reasons.

  • Fatigue, tiredness, or drowsiness
  • Sleeping disorders like narcolepsy or sleep apnea
  • Bleeding surrounding the heart
  • Side effects of certain medications that are used to treat anxiety or depression

Excessive yawning is very common. But it could lead to serious things like heart attack, brain tumor, multiple sclerosis, epilepsy, liver failure, and inability to control the body temperature. If you notice that you yawn too much, talk to a doctor immediately.

Only a doctor can assure if the problem is because of a medical condition. You might want to try a new mattress!

How many yawns per day is normal?

Humans who sleep for about 8 to 12 hours, alternate between inactive and active periods tend to yawn more frequently through the circadian rhythm. In humans, the frequency of yawning varies from 5 to 15 times a day. 

According to Harvard Health Publications, an average person has about 10 yawns per hour. But frequent yawning can signal periods of tiredness.

This can happen because of depression or insomnia. It can also happen because of the side effects of certain medications, or other medical conditions.

Hence, the exact number of yawns per day which is normal might be hard to get. That’s because a lot of factors act on your body that results in a yawn. And, the fact that it is contagious, the right number of yawns could be a bit difficult.

Why do we stretch when we wake up?

It is the first thing that everybody does in the morning after waking up. You begin to roll, stretch your arms around, and give a good yawn. Then you move out of the bed and do the necessary things in the morning. A good stretch will make you feel so good.

A full-body stretch will wake up your muscles. Your brain seems to be awake, but your muscles are still in inert condition. Therefore, it needs a good stretch for your body to get going. A good stretch realigns and loosens the muscles.

It also helps in the circulation of blood flow throughout your body.

While you are asleep, your muscles lose tone and the fluid pools back around your back. This fluid gets into its normal position with the help of stretching. The muscles protect themselves by hampering the nerve impulses. 

However, after some time this mechanism becomes restrictive. When you stretch, it takes the muscles outside of their normal range. Stretching in the morning gives you a booster shot to set your day in the right way.


So, it is seen that there are many theories that support why people yawn. Various studies have shown that it regulates brain temperature.

You yawn more if you are tired of having less sleep. You can replace your pillow or mattress if you are not having deep sleep. 

I’ve done reviews on different pillow models like best Best Leg Elevated Pillow.

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