For centuries, people have pondered why we yawn at all. The answer in folk wisdom was often simple: we yawn when we are tired, bored, or lacking oxygen. However, new research shows that there is something more interesting and even more important for our health behind it than we might think.

Large-scale study on animals: who yawns the longest?

Did you know that giraffes do not yawn? Researchers from the Utrecht University in the Netherlands collected 1,290 instances of yawning, not only in humans but also in animals. They observed 55 mammal species and 46 bird species, from small mice to majestic giraffes and eagles. They found that animals with larger brains also yawn for a longer period of time.

Looking at the numbers:

• a mouse yawns on average only for 0.8 seconds,
  
  
• a human yawns for as long as 6.5 seconds.

The difference is evident and not random. Furthermore, a similar rule applies to many animals. With larger brains, it takes more time for them to cool down, hence the yawning is longer.
This confirms the hypothesis proposed by American researcher Andrew Gallup in 2007 that yawning is a natural way to cool the brain.

Why would the brain need cooling?

Our brains are like a computer. When they work too hard, they heat up. The body has various ways to cool them down. One of them is yawning. When we take a deep breath of cool air and stretch the muscles around our mouth, blood flow to the head increases. This allows cooler blood to reach the brain and cool it down.

Looking at birds, which generally have a higher body temperature (around 41 degrees Celsius), the difference with the outside air is greater compared to mammals. Hence, a shorter yawn is enough for them to achieve the same effect. For mammals, with lower body temperature (around 37 degrees in humans), it takes longer to achieve a similar effect.

In 2016, researchers examined yawning in 205 instances across different species, including humans. The same rule was once again confirmed: larger brains, longer yawns.

How often do we yawn in a day?

On average, a human yawns between 5 and 10 times a day, which may sound like a small number. But considering that we live an average of 80 years, that amounts to over 250,000 yawns in a lifetime. It's no wonder that in the past, people attributed a special meaning to yawning.

In folk beliefs, yawning was often associated with the soul. In some cultures, it was believed that when yawning, the soul leaves the body, so people would cover their mouths and even pray to remain protected while yawning. This habit still continues today, although we no longer think about the spiritual background.

Why is yawning contagious?

Have you noticed that you start yawning when someone nearby yawns? This is not just a coincidence. Scientists believe it is a kind of social bonding. When one person yawns, others often start yawning too, as if the group wants to synchronize their rhythm: whether for sleep, relaxation, or attentiveness.

This contagiousness has also been studied in animals. For example, dogs often start yawning when their owner yawns, indicating a close emotional connection between humans and dogs. Similar observations have been made in chimpanzees: yawning spreads within the group, which can aid in group synchronization.

Although it's not entirely clear why this happens, research suggests it's likely a combination of biology and social behavior.

Can we cool our brains at home?

When we talk about yawning, we are actually discussing one of the cheapest and most natural ways to regulate the body. It costs nothing, happens spontaneously, and serves a purpose. However, there are a few more things we can do to help our brains stay in optimal shape.

• Cool air: Opening a window or going outside for fresh air on hot days can trigger the body's natural cooling process.
  
  
• Water: The brain is composed of over 70% water. Dehydration can lead to impaired function, slower thinking, and fatigue. Drinking enough fluids is the simplest way to cool down and keep the brain functioning well.
  
  
• Rest: Lack of sleep is a major reason why we yawn frequently. Studies show that just 1 hour less of sleep per night can increase yawning frequency by almost 20%.
  
  Folk remedies and practices related to yawning
  
  In folk medicine, yawning was often understood as a sign that the body needs rest. Grandmothers would say that if a child yawns frequently, it's time to take them outside for fresh air or give them a warm cup of tea.
  
  Interestingly, some herbalists believed that more frequent yawning could also mean that the body is seeking balance. They would recommend teas made from lemon balm, chamomile, or valerian, which calm the nervous system. Today, we know that these herbs indeed contain substances that affect muscle relaxation and reduce tension.
  
  In 2020, when the COVID-19 pandemic changed our habits, scientists observed an interesting phenomenon. People working from home and spending more time in front of computers often reported increased yawning. This was associated with less movement, poor circulation, and increased fatigue. A study on 1,500 individuals in Europe showed that 68% of respondents reported more frequent yawning during the lockdown.
  
  But in 2025, researchers went even further. Using smart watches and sensors, they monitored breathing and yawning in thousands of volunteers. The results suggest that the length of yawning could even help predict brain fatigue and decreased concentration. This means that yawning could become a natural alarm in the future, alerting us when it's time to rest.
  
  What do modern findings mean for us?
  
  Although yawning may seem unimportant, it actually tells us a lot about our bodies. It tells us when we're tired, when we need fresh air, and when our brains are overloaded. The length of a yawn is closely linked to brain size, making it one of the longest in the animal kingdom for humans.
  
  It's important not to try to suppress yawning. It's a natural reaction with a purpose. Although sometimes not the most appropriate (in a meeting, at the theater), it's good to allow the body to do what it needs.
  
  Conclusion
  
  Yawning is not just a sign of boredom or tiredness. It's part of our biology that allows our brains to remain cool and efficient. The length of yawning reveals more than we might think. In humans, it is on average 8 times longer than in mice, highlighting the importance of this process for our complex nervous system.
  
  If we add folk wisdom to this, we can say: when you yawn, listen to your body. It might be telling you that you need a break, fresh air, a sip of water, or a few minutes of rest. This is the cheapest and most natural remedy that we all have at our disposal, or rather in our lungs...