Ever Wonder Why Noses Run, Stomachs Growl, and Yawning Is Contagious?

Why do these strange, frequently annoying phenomena happen in our bodies?

Let us dissect it and reveal the intriguing science underlying three commonplace physiological mysteries.

1. What Causes Your Stomach to Growl, Especially in Extremely Silent Conditions?

We often attribute it to hunger, but borborygmi, or stomach growling (yes, it has a name), is more than just a sign of hunger.

What is Actually Taking Place?

Peristalsis is the term for the muscle contractions that propel food, gas, and liquids through your digestive system as your stomach and intestines move continuously.

Those contractions can be more intense when your stomach is empty or almost empty, and they reverberate if there is no food to absorb the sound.

The noise is simply your digestive system working, much like a washing machine in the middle of a cycle, even though it frequently occurs while you are hungry.

Fun Fact: You can temporarily stop the growls by drinking water or eating anything tiny, but they will return. It is the background music of your gut.

2. What Causes Your Nose to Run When You are Emotional, Cold, or Sick?

That runny, dripping nose? It is essentially a defense mechanism, not merely a cold symptom.

This Is the Reason Your Nose Runs:

Tiny glands that create mucus, a sticky, germ-trapping super hero, line your nasal passageways. Your body produces more mucus when you are ill, exposed to chilly air, or even while you are sobbing.

Catch viruses and bacteria

Wet the arid air.

Eliminate irritants

The innumerable tissues are caused by an excess of this protective fluid when your immune system is overactive, such as when you have a cold.

Hold on—Why in the cold?

Your body produces more mucus to warm and humidify the air you breathe before it reaches your lungs because cold air irritates the tissues in your nose.

3. What Causes Yawning to Spread?

Before you know it, you are yawning too after seeing someone else do it. 

Although scientists are not quite certain, this is the main theory:

It is possible that yawning developed as a social bonding trait. It is believed that empathy and mirror neurons—the brain circuits that enable us to imitate the emotions and behaviors of others—are linked to contagious yawning.

Humans and primates are the most likely to yawn, and we are more likely to "catch" one from a familiar person.

In summary, your body is strange—and amazing.

Our bodies have many peculiarities that appear random, but typically have a clever function, such as synchronized yawns, snotty noses, and rumbling stomachs.Therefore, do not feel ashamed the next time you yawn because someone else did, your nose runs on a date, or your stomach growls during a Zoom call.