25 Weird And Interesting Facts About The Human Body And Brain
Let’s face it: Human bodies are weird. They’re also an endless source of fascination for kids, given the plethora of strange and gross stuff going on inside of us at any given moment. Should your kids know everything there is about their boogers, brains, and bodies? Of course they should. Give the weird facts about bodies to them straight. Our bodies are strange, sure, but they’re part of our world and every fact about it, no matter how gross, is a lesson in celebrating both science and ourselves. It may get weird, but don’t hesitate to share — think of it as a celebration of our wild and wonderful body after all.
1. You’re Taller in the Morning
You may not be at your best first thing in the morning, but you are at your tallest. While we stretch out to sleep at night, gravity gradually compresses cartilage in our spines and knees throughout the day, bringing us down. Interestingly, when astronauts come back from space, they are a few inches taller because of the lack of gravity they were exposed to, before gradually returning to their own size.
At 5’ 7”, that explains why Jeff Bezos went to space, and why you should measure your kids for their latest height notch on the wall before breakfast.
2. You Can Pinch a Weenus as Hard as You Want
Forget occupying your kid with a book or screen. There is no better juvenile distraction than playing with your weenus. The extra skin on your elbow, known scientifically as olecranal skin or colloquially at the weenus, is basically nature’s Silly Puddy because there are fewer sensory neurons located there. That means you can keep kneading it all day long, and as hard as you want. That’s not to say that you can’t injure your elbow in other ways like playing tennis or overdoing it at the gym, but treating your extra skin like a stress ball is fair game.
3. Your Brain Is Fat
Your brain is the fattiest organ in your body, composed of approximately 60% fat. And that is exactly how voluptuous it should be, because the brain needs essential fatty acids in order to perform adequately, and imbalances could increase the risk of developing neurological diseases such as ADHD, Alzheimer's, schizophrenia, and depression. So instead of worrying about belly fat, praise your fat operating system upstairs for keeping your body in check. Perhaps rappers should’ve been praising your juicy cerebrum all along.
4. But It Shrinks When You Become a Parent
Scientists believe that having a baby changes the brain of new mothers, resulting in less gray matter in areas of the brain involved with responding to social signals and general processing. However, new research recently revealed that dads experience similar shrinkage in their brains in regions related to executive functioning and visual processing.
In both experiments, the researchers concluded that all of these neurological changes are normal and likely a biological response to enhance different parenting roles. So bring on that baby brain.
5. Your Brain Starts Slowing Down at 24
If you were worried you peaked in high school, add about a decade to that and scientists would agree. A study of 3,305 people ages 16 to 44 first detected declines in cognitive speed at age 24, which dropped by about 15% for every 15 years after that. If you’re closing in on 40, these numbers may take a bit longer to crunch, but it adds up to your quickest days being behind you.
6. You Lose Bones as You Grow
Babies are born with about 300 bones in their bodies, but as we grow up and mature, this number gets whittled down to about 206 bones. So what the hell happened to turn your skeleton into a bone vortex? Here’s the thing. Infants are made up of many smaller bones and more cartilage so they can bend and adjust to the womb and birth canal. But as they grow, these bones fuse together, decreasing the number of bones overall. So baby bones aren’t up and disappearing; they’re just teaming up.
7. Your Pinky Is the Strongest Finger
Despite the notion that the pinky contributes half of our grip strength, it’s closer to a third, which is still pretty impressive for the tiny fifth finger. Research shows that the pinky and ring finger account for about 54% of grip strength, but of the powerhouse pair, the pinky accounts for 33% of that strength. So it’s still the strongest of all five fingers overall, and arguably worthy of every ring put on it.
8. A Quarter of Your Bones Are in Your Feet
For only making up a small portion of your body, your feet contain 26 bones per foot, 52 total, accounting for about a quarter of the bones in your entire skeletal structure. Between the14 phalanges, 7 tarsal bones, 5 metatarsals, and 2 sesamoids, on top of over another 33 joints and hundreds of ligaments, your feet are far more than a few little piggies who went to the market. They are 52 out of 206 bones all together, or one fourth of your bones. They should be respected as such — even if they are ticklish.
9. The Strongest Muscle in the Human Body Is the Jaw
Forget working out your lats, biceps, or glutes. You were already exercising the strongest muscle in the human body when you were housing a burger and talking trash with your buddies, because the strongest muscle in the human body is the masseter, aka the jaw. A healthy jaw is capable of closing a set of teeth with a force of up to 200 pounds, according to the Library of Congress. If you were looking for an excuse to refer to snacking as “strength training,” now you have it.
10. There’s a Difference Between a Grower and a Shower
It’s not just an expression about boners. One study found that some penises experience notable size changes over four centimeters — the minimal cutoff for being considered a “grower” — whereas some guys experience very little size changes when aroused, regardless of what they were working with to begin with. They also found that “growers” tended to be younger men, so it’s possible to age into being a “shower.”
11. Vaginas Change Size Too
Dudes aren’t the only ones experiencing fluctuating genitals, and given the logistics of sexual intercourse, this makes some sense. Research shows that vaginal depth ranges from 2.7 to 3.1 inches. But in a state of sexual arousal, this can increase to a range of 4.3 to 4.7 inches. So while men are growers and showers, ladies appear to have more depth.
12. Vaginas Are Like Wine — They’re Acidic
A pH value is meant to measure how acidic something is, which is important for anyone with a vagina because that score could leave you susceptible to a number of uncomfortable infections. However, there’s one relatively easy way to remember the healthy pH level for a vagina, which is around 4.5 — it's a similar pH range as wine. Of course, sharing this information will probably make any wine tasting or prenatal appointment very weird. But that doesn't mean you’re wrong.
13. Stomach Acid Can Melt Metal
If you’ve ever had heartburn so bad that it felt like your burps could melt faces, you might be onto something. The digestive juices in the gut contain hydrochloric acid, which can dissolve certain metals like zinc and falls just below battery acid on the pH scale. One study found that gastric acid could even partially break down razor blades, but not copper, so it’s a mixed bag. But you may want to pack Tums just in case.
14. Your Intestines Are Always Moving
If you’ve ever wondered why your stomach makes noises, the grumbling is likely a result of a process called peristalsis, an automatic and continuous wavy movement of the muscles that line your gastrointestinal tract, which aids in digestion. (Or when the vomiting reflex is triggered, and muscles move the food backwards, up the esophagus and out the mouth, it’s known as reverse-peristalsis.) So if your gut is making noise, it’s also probably doing the wave as well.
15. Some People Can Give Themselves Goosebumps
Goosebumps are caused by tiny arrector pili muscles that contract and raise the hairs on your skin when you're cold, being tickled, or experiencing other types of sensory stimuli. This is known as piloerection, which is a fun enough word in itself. But even creepier, there are some, albeit a small amount of people, who can contact these muscles consciously and can give themselves goosebumps on command, like a deranged party trick. Maybe that’s what R.L. Stine was writing about all this time.
16. You Produce Up To Four Pints Of Spit Per Day
Saliva serves an important function of neutralizing harmful stomach acid, killing germs, and helping prevent tooth decay, gum disease, and bad breath, so it’s a good thing that you make a lot of it. Although the commonly circulated figure is about two full swimming pools of spit in a lifetime, or 25,000 quarts, this doesn’t appear to be verified in any scientific way. However, Live Science estimates that the average person produces about two to four pints of spit per day. Cheers to the foam on your beer for not being that.
17. The Human Body Technically Glows In The Dark
Similar to glow worms and fireflies, humans are bioluminescent, meaning we emit light. This is mostly as a result of a metabolic reaction in which free radicals are produced through cell respiration, causing us to glow. The big difference between humans and fireflies is that the light we produce is about 1,000 times weaker than the human eye can detect. However, at least one study has captured the glow though ultrasensitive cameras. It’s worth noting that researchers found that the light was at its highest in the afternoon and was the brightest in the cheek, forehead, and neck areas — in case they ever make a blacklight for that.
18. Your Fingernails Grow Three Times Faster Than Your Toenails
The main reason people bite their fingernails more than their toenails may not be because it’s marginally less gross and requires less acrobatics, but because they have more raw material to work with. Studies and dermatologists alike confirm that fingernails grow about three times faster because your hands have more blood pumping through them due to closer proximity to the heart, which facilitates growth. That’s also why your fingernails grow at a slower rate in colder weather — because blood flow is being restricted.
19. Women Blink More Often Than Men
Although blinking doesn’t seem like it should be gendered, women blink about twice as often as men. Specifically, women have been found to blink 19 times a minute compared to 11 times a minute for men. Researchers believe this has to do with the hormone estrogen, which can make the cornea more elastic and change how light travels through the eye, making women more susceptible to blinking. Likewise, as women’s estrogen levels decrease, their rate of blinking also declines. In other words, your spouse may not be batting her eyes flirtatiously, she just has more estrogen than you do.
20. Men Are More Sensitive to Coffee
Sex hormones like estrogen may also be why women appear to be less reactive to caffeine. One study found that men were more responsive to a single dose of 100mg of caffeine in regular coffee than women, whereas women reacted more to decaf coffee. An additional study confirmed that higher levels of estrogen in women were similarly linked with being less affected by caffeine, indicating that estrogen is to blame for this sex difference. Add that to your long list of reasons to never tell a woman she looks tired. It’s not her fault the Starbucks didn’t take.
21. Your Liver Can Regenerate Itself
The liver is the only organ in the human body that can regenerate itself, a phenomenon that’s been recognized since the days of Greek mythology and has since been confirmed by modern science. Although some injuries and diseases can damage the liver beyond repair, the organ has the capacity to regenerate itself even after 90% of it has been removed, according to the National Institutes of Health. That’s why unlike kidney donors who give up one of their two organs, liver donors only have to give up a piece of theirs, which will grow back on its own. Maybe that’s why it’s called the liver, because like Matthew McConaughey in Dazed and Confused, it just keeps on livin’.
22. Pus Is Just White Blood Cells
As disgusting as pus is, it’s an important indicator that your body is working as it should. That's because the gross, white (and occasionally yellow, green, and brown) substance is a product of white blood cells building up, which is a result of a healthy immune system that responds effectively to infection. There are some exceptions, like after major surgery, when pus is a cause for concern and a reason to contact your doctor. But in the case of smaller injuries, pus is a sign of a good and gross job done, in terms of healing.
23. Twins Smell The Same
If having the same DNA weren’t enough, the weirdest thing about identical twins is that even if they don’t share matching outfits, they still share a scent. Studying the scents of identical twins, Swiss researchers discovered that twins smell 10 times more similar compared to non-related pairs. This was expected, as our body odor is thought to be rooted in genetics. But now you know dogs probably can’t tell twins apart either.
24. New Species Of Humans Are Still Being Discovered
As of right now, there are 21 known species of human, and the Homo longi was uncovered as recently as 2018. Scientists have also discovered hybrids of some human species, such as a girl with a Neanderthal mother and Denisovan father known as Denny. In case it’s not clear what species your screaming toddler is, they’re a Homo sapien, allegedly.
25. The Brain Can Survive After Death for Longer Than You Think
Typically, a person is considered legally dead when their heart stops beating. However, science is constantly evolving, and experts are constantly discovering new things about life and death. As pulmonologist and critical care expert Sam Parnia told the New York Academy of Sciences, we used to think a person had a few minutes after their heart stopped before their brain cells died from lack of oxygen and ceased to function, but now we know that’s not true either.
“You have hours, if not days, before the brain and other organs in the body are irreversibly damaged after death,” Parina explained. From there, your brain and cells go through a secondary death process, which is why there are people who’ve been declared dead but came back to life. “So, this accelerated secondary injury process is what we need to combat in medicine now,” he added.
As much as he’s not a fan of the imprecise term “near death experience,” Parina conceded that this phenomenon does occur. And sure, that may be a heavy concept for a kid to grasp, but it could provide comfort to parents that scientists might figure out how to keep the lights on upstairs longer. That way you can regale your great-great-great grandkids with some of the aforementioned facts, which hopefully haven’t changed too much by then.