Believe it or not, our relatively tiny human teeth are just as strong as shark teeth. Although a shark’s tooth is made from a harder material, the enamel that covers both a shark tooth and a human tooth is comparable in toughness. Even so, I still wouldn’t recommend getting into a bite-fight with a shark.

When we blush, it’s not just our face that turns red–our stomach will turn red as well. Blushing causes the capillaries in our blood to widen, leading to increased blood flow and the red color that we see on our faces. Sometimes you just can’t hide what you are feeling, your body will give you away.

Our brains can do some incredible things. And these accomplishments are due to the constant barrage of electrical signals and impulses that are being sent between billions of nuerons. If you combine all of these together, you can power a low-watt light bulb.

Having a broken heart is painful. But did you know that your feelings of loss and sadness are actually a legitimate medical condition? It is called broken heart syndrome and it can cause chest pain and shortness of breath. Don’t worry though because the symptoms–just like the pain of your unrequited love–will fade over time.

I’m sure we’ve all made some pretty strange faces over the years, but did you know that we are capable of making up to 7,000 different facial expressions? This is largely due to our plentiful facial muscles. We’ve evolved to have more muscles and less hair on our face than our primate ancestors so seeing these expressions is much easier than it used to be.

Ever heard of exploding head syndrome? Yeah, me neither. Apparently, it causes you to hear a sound like a loud gunshot or an explosion right before falling asleep or as you wake up. It’s estimated to affect up to 10% of the population.

Our hair is stronger than we think. It is resistant to many different types of chemicals and acids and its only real threat is fire. Otherwise, because it decays at an extremely low rate, your hair will stay intact for a while. However, there’s no guarantee that it will stack intact while remaining on your head. Sorry, guys.

I’m the type of person that will eat anything. However, some people suffer from a disease called Gourmand Syndrome. It’s caused by an injury to the right anterior cerebral hemisphere of the brain and will create a preference for eating and thinking about fine foods. In terms of disease, this one doesn’t sound too bad… just as long as you’ve got the money to afford it.

Our stomach acid is no joke. The hydrochloric acid that our body produces isn’t just strong enough to break down food, it is also strong enough to bore through wood. Let’s just hope that our stomachs never spring a leak.

There are many techniques out there for relieving stress. One of the most simple, however, is blowing on your thumb. This cools your thumb down and calms its pulse, which, in turn, causes you to feel more generally relaxed.

Your mouth is home to over 600 documented types of bacteria. They thrive in its warm and wet environment and can number in the billions. That’s why bites that break the skin so commonly become infected, it’s not teeth that you’re getting in there.

Although babies are obviously much smaller than adults, they actually have more bones than we do. This is because humans are born with 300 bones, but over time, many of those bones fuse, leaving us with only 212 once we are fully grown adults.

Our bodies contain a huge amount of blood vessels. We have arteries, capillaries, and veins which all contain them. They exist in nearly every inch of our limbs and if you were to line them up and stretch them out, they would reach anywhere between 60 and 100 thousand miles.

Our eyes are able to see at a resolution of 500 megapixels. To be clear, this estimate includes our entire field of vision spanning 180 degrees. Most cameras would be unable to match this–only a very high definition one could. Because of this, our eye is superior to most other devices.

Our skin accounts for about 16% of our body weight. That means for the average adult, their skin weighs about 20 pounds. If we could peel that off and line it up, it would cover around 22 square feet.

Believe it or not, we have mites living on our eyelashes and other hair follicles. The type of mite that inhabits our hair is known as Demodex. They are also considered to be a possible culprit for the various skin disorders that exist in people.

We often think of bones as being complete in their development. But bones are constantly regenerating. So much so that every ten years, the human skeleton completely regenerates itself. This process never stops but it does slow down as we get older.

The heart is a powerful muscle. It is so strong and creates so much pressure, that it can squirt blood up to 30 feet. And it needs to be that strong because the heart is tasked with pumping 2000 gallons of blood every single day.

Our eyes are closed 10% of the time that we are awake. This is mostly due to blinking, which we do a lot. It may seem like just a split-second closure, but the average person blinks about 15 to 20 times every minute. That starts to add up over the course of a day.

Even when our hearts leave our bodies, they can continue to beat. This is the main reason why we can do heart transplants between people. Doctors will keep the heart beating while it is transported to the patient–this procedure is done almost 5,000 times every day.

Your kidneys filter all of your blood at least 25 times every day. This process is crucial to keeping your blood and body healthy and it’s no easy feat for the kidneys. The average person contains seven or eight liters of blood which comes out to about 180 liters of blood being processed every day.

Tumors are commonly found growing on the skin or organs. However, did you know that there is a specific type of tumor that only grows on hair, teeth, and bone? It’s a type of cyst that’s called teratoma and it grows on just these areas of the body.

If you go back far enough along the evolutionary ladder, humans have a common ancestor with birds and reptiles. And believe it or not, we still have some parts of our bodies that are directly related to these ancient ancestors. The pink corner of our eye is actually the remnant of an inner eyelid that is similar to those that birds and reptiles have.

When you wake up in the morning, you are actually taller than you are when you go to bed at night. This is due to the fact that over the course of the day, the gelatin-like material that exists between the discs in our spines become compressed. But once we lay down for sleep, that compression is relieved.

The liver is a super cool organ. If you were to take away 75% of your liver, not only would it survive, but it would also regenerate back to its original size. It’s the only organ in the body that is capable of this incredible feat.

Once you hit 30, you actually start to get shorter. Every ten years you will lose about half an inch off of your overall height. This is due to the fact that the discs between our spine begin to flatten over time. However, don’t be too worried. This happens so slowly that most people won’t even notice your change in height.

Our heartbeats have the ability to change based on the tempo and beat of the music that we are listening to–it will either speed up or slow down. Not only this, but songs that contain crescendos can actually cause the blood vessels in our cardiovascular system to constrict.

Enjoy your favorite foods while you can because they won’t always be as delicious to you as they are now. We are born with about 10,000 taste buds, however, as we get older, our taste buds begin to disappear and things start to taste differently to us. Really, our taste buds only last around ten days before changing.

There are enzymes in our body right now that digest our food. However, these are the same enzymes that digest our body after we die. These microbial organisms will feed on the fluids produced from autolysis which takes place once we die.

Who doesn’t love kissing? Well, if you needed any more reason to kiss your significant other, then this is it–kissing reduces cavities. This happens because when you kiss, your mouth produces more saliva which washes plaque from your teeth. If you have less plaque on your teeth then you’ll have fewer cavities as well.

We are made of billion-year-old stardust and have about 97% of the same atoms as the milky way galaxy. This came to be because when stars explode, the dust forms new planets, and, eventually, people. It is believed that about 93% of our body mass is actually stardust.

Believe it or not, we are actually bioluminescent. This means that we give off light when we’re in the dark. However, the amount of light that we give off is far too faint to see. Other animals like jellyfish and fireflies display their bioluminescence more strongly than we do.

Our hearts are workhorses. They contract over 100,000 times every single day and never stop pumping. So over to the course of our life, our heart will pump through 200 million liters of blood.

During the 1940s, about 75% of Americans claimed that they rarely dreamed in color. This is thought to have taken place because of the black and white films and television that were so common back then. This phenomenon is much less common today.

The heart isn’t the only workhorse in the body, our mouths are working overtime as well. Our salivary glands are super sensitive, producing saliva even when we’re just thinking about food. And when there’s actually food involved, those glands are working even harder.

This reflex is triggered when we are submerged in water. The body shuts down certain areas to conserve energy and these changes can be observed physiologically. It would seem, based on research, that we have had quite a long aquatic history.

DNA molecules are the building blocks of life–and we have no shortage of them in our own bodies. If all of your DNA was uncoiled, it would stretch all the way to the edge of the solar system and back again. We have about 2 meters worth of DNA in every cell of our bodies.

We cry for many different reasons and, like those reasons, our tears will be different as well. In total, we have three different types of tears and the composition of each tear will look different under a microscope depending on why we are crying.

The human body varies greatly, so the number of soap bars it could be made into will vary as well. But on average, our bodies contain enough fat to make 10 bars of soap. Personally, I’d prefer not to use human soap the next time that I take a shower.

Our eyes are one of the coolest parts of our bodies based on how they look. But that’s not the only thing that makes them cool, they also are the only part of the body that doesn’t receive blood and the oxygen that it carries. This is because the cornea receives oxygen directly from the air that it is exposed to.