Science, Now + Beyond

These 13 facts about the human body will both amaze and gross you out

If ever you find yourself stumped for icebreakers, throw some of these human body facts into a conversation.

The human body is an intricate, fascinating, and complex thing. Its many detailed systems work together in complete symbiosis for us to function properly. Yet, we’re barely aware of our own body’s minutia and its capabilities.

Relatively speaking, these details could be construed as beautiful… or gross. Interesting nonetheless!

1. There are mites living in our eyelashes

A microscopic image shows a worm-like organism with a long end, eight tiny legs in front and a small head.
[Image description: A microscopic image shows a worm-like organism with a long end, eight tiny legs in front and a small head.] Via K.V. Santosh on Flickr
Yup, there are insects on your lashes rn.

Fear not though, as they’re just chilling and munching away on the dead cells. It’s a natural occurrence. However, if you start noticing sudden roughness, itchiness, and redness, a trip to the GP would be best as there might be an outbreak.

2. We produce between two to four pints of saliva a day

An animated clip shows a balding yellow man. His head droops back as his mouth falls open and drool collects.
[Image description: An animated clip shows a balding yellow man. His head droops back as his mouth falls open and drool collects.] Via GIPHY
That’s about one to two liters of spit. Daily.

Saliva may be mostly water but it plays an important role. Not only does it keep your mouth moist and comfortable but it helps ease digestion by softening your food, otherwise it would feel like sandpaper on your esophagus. The enzymes in your spit are also crucial for fighting off infections and bad breath.

3. Your heart pumps with enough pressure to squirt blood 30 feet across a room

An animated clip shows a heart pumping.
[Image description: An animated clip shows a heart pumping.] Via GIPHY
That’s about a four-story height. The reason why the pressure is high is because the heart needs to get the oxygenated blood through the human body while fighting resistance from muscles and tissue.

With that in mind, it’s important to seek immediate medical attention in case of serious cuts as the pressure is enough to lead to quick and large amounts of blood loss.

4. There are more bacteria living in your mouth than there are people on Earth

A microscopic image shows strings of light green, worm-like organisms.
[Image description: A microscopic image shows strings of light green, worm-like organisms.] Via Gerd Altmann on Pixabay
There are just over seven billion people on Earth and between 20 to 100 billion bacteria in any one person’s mouth alone.

In fact, your weight consists of two to six pounds of bacteria. Those who practice regular oral care will find 1,000 to 100,000 bacteria on each tooth surface, and those who don’t might find between 100 million to one billion growing on each tooth.

5. The stinkier your fart, the better you’re supposedly eating

A cartoon clip shows a blond teenager fart in the form of green gas. He looks embarassed as he tries to wave it away.
[Image description: A cartoon clip shows a blond teenager fart in the form of green gas. He looks embarassed as he tries to wave it away.] Via GIPHY
Bonus fact: everyone farts around 20 times a day.

However, not all farts are equal. Some should come armed with a hazard sign and gas mask. Fiber-rich foods make you fart more while high-protein ones contain a higher sulfur composition ipso facto stinky farts – good gut health though!

6. If all your blood vessels were laid out, they’d circle the globe at least twice

A microscopic image of inside a blood vessel is shown. Red Blood Cells - tiny, circular discs - are floating.
[Image description: A microscopic image of inside a blood vessel is shown. Red Blood Cells – tiny, circular discs – are floating.] Via Arek Socha on Pixabay
There are three types of blood vessels – arteries, veins, and capillaries. If they were laid out end-to-end, a child’s blood vessels would stretch over 60,000 miles while an adult’s would be over 100,000 miles. In a lifetime, your body pumps near one million barrels of blood – that’s enough to fill more than three supertankers.

7. There is a kind of tumor which can grow hair and bone, sometimes in the form of teeth

The image shows a tumor. It's browning and shows bone growth in the form of teeth.
[Image description: The image shows a tumor. It’s browning and shows bone growth in the form of teeth.] Via phys.org
As if the concept of cancer wasn’t already terrifying.

This type of tumor is called a teratoma and typically forms in the ovaries, testicles, and tailbone. There are two types, mature and immature, with the latter being more at risk of being cancerous. The etymology of the word can be traced back to Ancient Greece, and means “monstrous tumor”.

8. After the age of 40, it’s typical to lose a half-inch in height every 10 years

An animated clip shows a blonde girl drink a potion and then shrink down considerably.
[Image description: An animated clip shows a blonde girl drink a potion and then shrink down considerably.] Via GIPHY
When our body is young, it’s good at building bone mass. Though as we age, it seems like the human body deems it’s time to close up shop – typically around 35-40 – and bone breakdown happens quicker than growth.

It’s even worse after menopause or if you have osteoporosis.

9. The first part of a baby developed in the womb is the anus

A lit-up outline shows a fetus floating against a black background with an umbilical cord attached.
[Image description: A lit-up outline shows a fetus floating against a black background with an umbilical cord attached.] Via Raman Oza on Pixabay
What better way to humble oneself than hearing that we were all little assholes at the start. It’s not as disturbing as it sounds though. Our first few weeks in the womb were as a small group of cells – scientifically known as a blastula. This bursts creating an opening called a blastopore which is, unfortunately, a tiny anus. 

10. Your pinky finger is just as important as your thumb

Two people are holding hands via their pinky fingers. One has a navy sleeve and leather watch, the other is sporting a denim sleeve.
[Image description: Two people are holding hands via their pinky fingers. One has a navy sleeve and leather watch, the other is sporting a denim sleeve.] Via Ryan Franco on Unsplash
Turns out, your pinky finger has more importance to it than just making promises.

In fact, losing a pinky is like losing 50 percent of your hand strength. Do a little experiment right now – grab whatever is closest to you with your pinky, then without, and you’ll notice a considerable difference in grip strength.

11. Your brain can, theoretically, hold up to 2.5 petabytes of information

The image shows a number of lit-up spiky organisms. These are neurons.
[Image description: The image shows a number of lit-up spiky organisms. These are neurons.] Via Gerd Altmann on Pixabay
That’s over a million gigabytes.

This vast storage space comes from neurons combining together to sustain memories, exponentially increasing our brain’s capacity to store. It’s the equivalent of over three million hours of television. We could even fit the Internet in our noggins!

12. When you blush, your stomach does too

A blonde woman in a white dress blushes as she smiles and looks away shyly.
[Image description: A blonde woman in a white dress blushes as she smiles and looks away shyly.] Via GIPHY
Isn’t that just cute?

It happens because your sympathetic nervous system starts producing adrenaline which gets the blood flowing throughout your body, and as a result, your stomach reddens. One can’t help imagining an anime stomach being embarrassed and flustered – adorable!

13. The cornea is the only part of the human body which receives no blood supply

The image shows a colored sketch of an eye with a blue-green iris.
[Image description: The image shows a colored sketch of an eye with a blue-green iris.] Via InspiredImages on Pixabay
It gets oxygen directly from the air as there are no blood vessels on the cornea (the transparent bit of the eye), the growth of which are prevented by the large stores of protein present on the cornea. This bit of discovery launched a number of researches on how to slow down/stop vessel growth which led to the anti-angiogenic drugs which slow down tumor growth.

If ever you find yourself stumped for icebreakers, throw some of these human body facts into a conversation. Numbers 1, 7, and 11 are sure to get a discussion going.