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there are lots of creepy things about humans you might not have realized
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35 Creepy Facts About Your Body You Probably Never Knew

Ever thought about how much your skin weighs?

by Lauren Schumacker
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The human body is an amazing thing. There are so many different things your body does (or can do) on a regular basis that you might not even know about. But there are also some things about your body that are weird or even downright creepy. Some of the creepy facts about humans and their bodies will likely surprise you a bit, while others, though strange, really do make sense if you think about them. As interesting as the human body tends to be, it's also awfully mysterious, so if this isn't something you've studied extensively, there are a lot of facts that are fairly unknown to many people.

Even if you think you know a lot of weird and maybe even slightly disturbing facts about the human body, there's always much always more to learn. Not only that, but some conventional wisdom about human bodies is actually more old wives' tale-like than actual, true fact. Though knowing some of the stranger, scary facts about humans may not really have that much of an impact on your day-to-day life (and some of them will probably gross you out a little bit), they can definitely make you more in awe of all that your body is and can do.

1A quarter of your bones are in your feet

It sounds like it can't possibly be true, but it is. Dr. Sarepta Isaac, DPM, a podiatrist in Atlanta, tells Romper that you have 26 bones in each foot, which means you have 52 in both feet. And since you have just over 200 bones in your body, that's roughly a quarter in just your feet.

2Mites might live in your eyelashes

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As gross as it sounds, it's true. Mites really might live in your eyelashes. In fact, many people have mites living in hair follicles. In one 2014 study published in Archives of Medical Science that sought to study the prevalence of these mites, research showed that 41% of the people had them hanging out in their eyelashes. Typically they're not that big of a deal, but they can sometimes cause some irritation.

3Women’s hearts beat faster than men’s

There’s a noticeable difference in heat beat rates between men and women. The average human adult male heart rate is between 70 and 72 beats per minute, while the average for adult women is between 78 and 82 beats, which is significantly faster, according to a 2014 published in the Journal of Clinical and Diagnostic Research. This difference is most due to the fact that female hearts are generally smaller, and thus pump less blood with each beat and need to beat faster in order to reach the a stable heart output. However, it’s not only due to size differences, either — the study states that women actually also have a different intrinsic rhythmicity to the pacemaker of their hearts, causing them to beat faster.

4You make up to 30 gallons of tears per year

Tears serve many purposes and are caused by many things — working through breakups, dicing onions, watching the movie Up, seeing Harry Styles live, and so on. Your eyes are basically producing them all the time. In fact, according to the American Academy of Ophthalmology, you make 15 to 30 gallons of tears each year, which is an insane amount when you think about it.

5Fingerprints form around 23 weeks in the womb

Your unique finger markings actually form about halfway through your time spent in the womb. “Typically fingerprints are established around week 20 to 24,” Dr. Roohi Jeelani, FACOG, a reproductive endocrinologist and infertility specialist, previously told Romper. Around the same time, a baby’s feet will also begin to form the indentations and lines that will eventually make up their footprints.

6Your tongue print is individual

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You know your fingerprints are unique, but, as it turns out, so is your tongue print. A 2017 paper published in the Journal of Oral and Maxillofacial Pathology noted that it is useful in biometric authentication and could be helpful for other identification purposes.

7Blood pressure rises hours before you wake up

It makes intuitive sense that your blood pressure decreases while you're asleep. Interestingly, though, it starts to pick up steam a couple hours before you even wake up, not just getting higher when you're actually awake. According to a 2018 study published in Free Radical Biology & Medicine, this is because blood pressure is regulated by our innate circadian rhythm and internal clock.

8Your lungs aren’t the same size

You might think that your lungs would be the same size, but that's actually not the case. In fact, the right lung is bigger and weighs more than the left lung. Since your heart tilts to the left, the left lung is smaller and has an indentation called the cardiac impression to make room for your heart. At the same time, the right lung is bigger but also shorter because of the placement of your liver.

9There are a ton of “foreign” cells in your digestive tract

"There are more foreign cells or bacteria and fungi in your colon than human cells in your whole body," Dr. Glenn H. Englander, M.D., a gastroenterologist, tells Romper. That's something that could definitely creep you out a bit.

10Your stomach lining blushes when you do

When you blush, the lining of your stomach also turns a little bit red — so it's more than just an outward expression. This happens because blood rushes not only to the skin of your face when you blush, but also to the lining of your tummy.

11You can break a rib sneezing

It might not sound like something that's truly plausible — and it is quite rare — but according to a 2015 study published in the Asian Cardiovascular & Thoracic Annals, it’s possible to hurt yourself and even break a rib just by sneezing.

12Your height is approximately equivalent to your wingspan

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Many of your body measurements are approximately equivalent even though you might not expect it. Your height is about the length of both of your arms (your “wingspan”) when they’re outstretched, as exhibited in many studies such a 2020 one published in Journal of Family Medicine and Primary Care. Some professional experts can use these different measurements to put together an idea of what someone from the past might have looked like.

13Your mouth makes a lot of saliva every day

It might seem like way too much, but your salivary glands typically produce anywhere from 0.5 and 1.5 liters a day, according to a 2009 study published in the Journal of Medicine and Life. For reference, that’s over 6 cups of liquid.

14Babies acclimate to taste through breastfeeding

Depending on what a birth giver or breastfeeding parent eats, a baby will actually innately get used to those tastes so they will be tolerant of them in the future. “Some flavors impact the taste of breast milk subtly, very similarly to amniotic fluid that gets swallowed by the baby in utero,” Ashley Georgakopoulos, Motif Medical lactation director and IBCLC, previously told Romper. “It's nature’s way of acclimating baby to foods they may later eat in their culture.”

15You have over 30 joints in your feet

Isaac explains that your feet contain 33 different joints, which seems like an awful lot for such a small area. But if you think about how many bones are in your feet and how they move, it makes more sense that there'd be so many joints.

16Babies have more bones than adults

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To begin with, babies have 300 bones in their body. “Babies are born with more bones than adults because some will eventually fuse together,” Jeelani said. “In fact, some aren’t true bones but are made up of cartilage which will eventually become bones.” Eventually, the bones will fuse together to become the 206 bones that adults have.

17Women deal with many issues due to pelvis shape

Those assigned female are birth are more likely to suffer from some conditions because of the way their pelvis is shaped, which affects how they sit and move during many different activities. In fact, nearly 24% of U.S. women are affected with one or more pelvic floor disorders, according to research funded by the National Institutes of Health.

18The liver can regenerate itself

You may have heard that you can donate part of your liver as a live donor, which you can't do for every organ. That's possible because your liver can then regenerate the part that was lost (and the part of your liver that you donated will grow as well). As recent as 2021, researchers learned more about what exact cells are responsible for liver homeostasis and repair, as published in Science.

19Humans are the only animal that blushes

This isn't just part of a Mark Twain quote — it's also true. As noted in a 2017 study published in Frontiers of Human Neuroscience, no other animal has the same emotional response as that of humans blushing, which can stem from not only embarrassment, but also pride, guilt, shyness, and shame.

20You can detect about one trillion different scents

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You've probably never thought about how many different scents your nose can tell the difference between between, but as it turns out, it's quite a lot. A 2014 study published in Science found that humans can detect about one trillion different scents, but noted that more research is needed and that the number might be even higher.

21You spend about 10% of your time awake blinking

A 2012 paper published in the Proceedings of the National Academy of Sciences reported that people blink about 15 to 20 times each minute, meaning, if you do the math, you spend about 10% of the time that you're awake blinking.

22You're at your tallest when you wake up

You might think you're the same height all the time, but that's actually not exactly true. In fact, laying down and sleeping relieves the compression of your spine, which allows you to "grow" just up to two centimeters taller by the time you wake up, as noted by researchers at the NASA Johnson Space Center's Habitability and Environmental Factors Office.

23Your small intestine is way longer than you are tall

Your small intestine is all coiled up in your abdominal cavity, so it's sort of difficult to grasp just how long it is. However if you stretched out your small intestine, it'd be about four times longer than you are tall. How about that?

24Many people’s mouths are constantly inflamed

"It is estimated that 75% of people have at least mild gum disease, with the most common symptoms being bleeding when brushing, bad breath, and dark and swollen gums," Dr. Ron Baise, a London-based dentist, tells Romper. "The first two of these symptoms are considered normal to a lot of people."

Estimates vary a bit, with some saying about 50% and others saying about 80% of people are dealing with some sort of gum disease. Still, the inflammation that comes along with gum disease isn't normal.

25Your heart might help you in the face of danger

A 2012 study published in Frontiers in Psychology concluded that your heart might be able to anticipate when something dangerous or exciting is going to happen, as your heart rate starts to pick up a bit before the actual event. So if you get that feeling, you might want to listen.

26Humans and chimps have the same hair density

Yes, you read that right. According to a 2018 study published in the Journal of Human Evolution, humans are indistinguishable in terms of hair follicle density from chimpanzees. Guess we’re not that different from primates, after all.

27Your pinkie fingers are super important

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Your pinkie fingers might have more of an impact than you would have thought. According to a 2010 study published in The Canadian Journal of Plastic Surgery, if you didn't have your pinkie finger, the overall grip strength of your hand would decrease by 33%. That's a whole lot.

28Humans give off a light that the eyes can’t see

You might not have realized you actually glow a little bit. A paper published in PLoS One noted that human bodies give off a little bit of light that the eyes can't see, suggesting that the body actually "glimmers."

29Your body smells different at different ages

A 2012 study published in PLoS One found that people smell differently at different ages. Though that characteristic "old-person smell" is well-publicized, you might have never thought that other age groups also have a scent.

30Stomach acid is super powerful

"The acid in your stomach is more powerful than any acidic food you can name," Englander says. You likely knew that stomach acid is relatively strong, but you might not have realized just how strong.

31Hair is really strong

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Though you might not think it, your hair is actually really strong — so strong that research has recommended studying it in order to apply its tensile strength to manmade materials. An entire head of hair can handle about 12 tons, which is, of course, quite a bit of weight. You can thank the long chains of the protein keratin for that strength.

32There are more than five senses

You've been told time and time again that most humans have five senses: sight, hearing, taste, smell, and touch. But that's not exactly all there is to it. The World Economic Forum noted that humans also have senses like proprioception, which is the sense of where your body is in space.

33Your skin weighs about eight pounds

You might not ever consider your skin in terms of how much it weighs, but studies estimate that that an adult's skin can weigh about eight pounds and measure about 20 square feet.

34There are hundreds of muscles, tendons, and ligaments in your feet

When you think about how many bones and joints are in your feet, that helps you better understand just how much is actually going on down there. "Yes, in such a small space, but it makes sense because the feet serve such a large function of literally carrying around the human body each day, from the time we learn to walk as toddlers to the time we become bed-bound in our later years," Isaac says.

35Blood is 10% of your body weight

You probably don't typically think of body weight as having to do with much beyond the muscles and fat stores in your body, but there's actually a lot more to it than you might think. Although the amount of blood in a person’s body depends on their size, blood is approximately 10% of an adult’s body weight, according to the Red Cross.

All in all, the human body is downright weird. But at the same time, it’s fun to learn about all of its intricacies. Next time someone asks you for a strange piece of trivia, hit them with one of these creepy facts about the human body.

Experts:

Dr. Sarepta Isaac, DPM, podiatrist based in Atlanta

Dr. Roohi Jeelani, FACOG, reproductive endocrinologist and infertility specialist

Dr. Glenn H. Englander, MD, gastroenterologist

Ashley Georgakopoulos, Motif Medical lactation director and IBCLC

Dr. Ron Baise, London-based dentist

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