The design of the human body is pretty neat: We are aware of when we are hungry and thirsty. The same eyes that can see clearly in blinding brightness can also see in almost complete darkness. When we cut our finger, the wound quickly scabs over and heals. Our bodies are generally good at fixing problems and recovering from illness. However, while it does more good than harm, flaws in the human body do exist.
The appendix is useless. Many individuals have crooked teeth and poor vision at birth. Women can pass away during childbirth because our hips are better evolved to support our internal organs while walking on two legs. To put it mildly, humans are flawed. These design flaws in the human body put humans at a disadvantage, with some people at a bigger disadvantage than others. Interested to learn more about flaws of the human body, a member of the AskReddit community ketra1504 asked fellow Redditors, "What is the biggest design flaw of the human body?". This, and a similar thread, got plenty of traction and revealed what most people deemed the biggest flaws of the human body. Regardless, we can't claim that evolution has gone wrong or done us dirty. We have changed a lot since our species first appeared. And although the remaining human body flaws are unlikely to disappear in the near future, we can only hope that we will be better at coping with them, which is, again, a massive win for humanity.
Below, we've compiled some of the most spot-on answers from the threads, revealing human body design flaws. As always, upvote the entries you agree with, and let us know, what's the biggest flaw of the human body in your eyes? Share your thoughts in the comments. And if you want to learn more about yourself and your body, check out our recent post featuring interesting facts about the human body.
This post may include affiliate links.
"How in your brain, your amygdala (fight or flight) hasn't learned to respond directly from your prefrontal cortex (the newer, more recently developed in the evolutionary sense part of the brain that you think rationally with). The fact that the amygdala hasn't adopted to modern times.
Amygdala: OMG ARE WE BEING STALKED BY DOZENS OF PREDATORS ABOUT TO KILL US WHILE WERE EXPOSED OUT IN THE OPEN?!?
Prefrontal Cortex: Lol nah bro it's good I'm just doing a presentation in front of my class.
Amygdala: PANIC ATTACK FULL ON SURVIVAL MODE IT IS!!!!"
The amygdala saved my life once, when I was nearly hit by a car and reacted before my neo cortex could respond. However, the amygdala usually causes tragedy. I am still haunted by the account of one father, who came home and his daughter wasn't responding to his calls. He got concerned, got his pistol and went to her room to see what was wrong. She was hiding in her closet and jumped out to scare him and before he had the chance to recognize her voice and face, the amygdala took over and shot her. She died. Now that I think on it though, how paranoid does he have to be to grab his GUN before just walking over to see if she is ok?
"It’s gotta be the female reproductive system. Debilitating pain every month shouldn’t be something that just happens to some women. Pregnancy is also way more dangerous for humans than most animals."
Its more dangerous due to the size of the human brain as I understand it. Maybe we should have evolved as marsupials.
GreedKite said:
"You can bite the inside of your own mouth."
gr8ydude replied:
"Then you proceed to accidentally bite, multiple times through out the day, that lump that develops."
ferox3 said:
"Allergies are basically your body jumping to conclusions about a harmless substance, and flying off the handle for no good reason."
slabby replied:
"So even my immune system has anxiety?"
SpreadingRumors replied:
"In the worst of cases, it occasionally decides to attack your own healthy organs, causing organ failure and requiring a transplant. Which, of course, the immune system will then ALSO try to attack the transplanted organ because it really IS a foreign object.
I hate my immune system."
duermando said:
"There is a fork in the road in our throats. One is meant for food, the other for oxygen. If food goes down the wrong one, you die."
thedomham replied:
"Or you cough heavily for a bit."
Well there is a cover in between that closes off the airhole while swallowing ;)
"Oh you're sick? Better completely block off half your nose so you can't breathe properly."
"That we cannot delete or sort unwanted/not needed info and memories from our brains."
insidli said:
"Vasovagal syncope from pooping."
trackofalljades replied:
"Pretty much everything neuro/muscular that results from putting the pooper right next to the babymaker would be my vote for design flaw numero uno."
"God must be a civil engineer, because who else would run a waste disposal line right through a recreational facility."
I0I0I0I said:
"That you can have excruciating pain from a tiny hole on your tooth, but you can get cancer and not know until it's too late."
eran76 replied:
"As a dentist, to be fair, its only a small hole at the surface but a massive area of decay underneath that's causing pain. Most truly minor decay is also painless."
It's because teeth have nerves to sense if something is wrong but cancer cells are just normal cells with an extra fast spawn time, no nerves to detect that, maybe if that growth starts pressing onto a nerve there would be pain involved
"Men have incredibly sensitive organs that are partly responsible for the procreation of mankind, as well as hormonal balances within the body. Instead of protecting these organs inside a ribcage or something, we dangle them outside our bodies, where they can be sat on, smashed, kicked, or otherwise injured."
User No 1 said:
"The need to sleep for at least 1/3 of the day."
MarcusQuintus replied:
"Humans are on the low end of the scale for sleep. Many animals spend >80% of their day sleeping."
leagueofuchiha also replied:
"I once read somewhere also that the state of sleep is lifes standard and primary state. We only wake up to nourish ourselves with food, water, and s**, and then return to our primary state. Were made to exist just so we can procreate."
Maybe its because we spend 80 percent of our time on the internet instead?
"Chronic pain. Yes I know my head hurts and my head will always hurt there is nothing I can do about it so shut the f**k up brain."
Mountainbranch said:
"Eyelashes falling loose and ending up in the one place they're supposed to prevent s**t from falling into."
Vaguely-Azeotropic replied:
"Oh hell, this. I take chemo shots every week for an autoimmune disease, and the worst part isn't the exhaustion, mouth sores, or easy bruising and bleeding - no, it's all the freaking eyelashes falling in my eyes the day after the shot. It's like the sad little Christmas tree in Charlie Brown where all the needles come loose after one good shake. And I'm on a low dose, so there are enough left for the same thing to happen the next week. Serious design flaw."
I was annoyed that my hair didn't come back in curly after chemo. Bummer.
etymologynerd said:
"Pimples."
_userlame replied:
"Speaking of pimples, why do we have to get acne on our faces more than anywhere else, the face is the absolute worst place for that s**t, I would 100% prefer to have pimples on my knees or elbows or forearms or anywhere other than the god damn face."
etymologynerd also replied:
"Clearly you're not speaking for my back here."
strykazoid said:
"The Obstetric Dilemma. Basically, the human body isn't built for easy birth."
RIPMYPOOPCHUTE replied:
"Also the fact that bleeding still happens in the first trimester, and the bleeding can follow the regular cycle or you can have spotting every week in the first trimester. My BIL’s girlfriend would have like a period the first 4 months of pregnancy. It’s wild, it’s terrifying, and it’s stupid."
User No 1 said:
"The spine seems to be ridiculously fragile. As does the neck."
Redditor replied:
"Having performed multiple cadaver dissections and seeing the spectacularly strong reinforcement of the spine that requires a bone saw to cut through, I beg to differ. Most spinal injuries take place via brutal shearing or compressive forces like those seen in car accidents or falls from a distance.
For day to day activities, the spine is wonderfully adapted to normal use for a lifetime."
well my spine decided to not be normal so here i am living with constant pain in my neck, shoulders, and ribs
"We have incredible cellular machinery designed to repair DNA, replicate DNA, and proofread DNA and destroy DNA if it's wrong.
But we have things at the end of our DNA called telomeres that get shorter throughout our lives. They get shorter and shorter and shorter. And that's how we age and eventually die (oversimplification).
Oh, and we have an enzyme that actually does replicate the telomeres, we just don't use it in the majority of our cells."
It's so we *can* die. From an evolutionary & environmental standpoint, all sexually reproducing organisms must.
"Erections. They're like neon signs pointing to things I'd rather keep private.
'No. I am not turned on... ignore that.'"
User No 1 said:
"That we lose a pretty good set of teeth at the age of 6. This would be so much more useful down the road, maybe at age 50 or 60, not 6, that's just dumb."
gigisilver replied:
"We would have to have a 3rd set for this to make sense due to head growth. Could you imagine how creepy and ineffective adult heads with those tiny baby teeth would be? Losing them young allows for bigger more efficient teeth to grow into the new jaw space."
"You can kinda just die at any moment from a brain aneurysm, even if you're perfectly healthy."
Gorf_the_Magnificent said:
"We have to wipe ourselves after we poop. No other animal has to wander through the forest looking for something soft and absorbent."
User No 2 replied:
"They have to lick themselves, though. At least we don't have to do that."
Young_Toast also replied:
"When we were actually being humans like, pre civilization, we ate very fibrous diets, leading to clean poops. Also squatting to take a s**t might've helped a bit."
ThePierceIsRight said:
"Our pelvis is extremely small and leads to a lot of complications when it comes to childbirth."
RebelStarPilot replied:
"I read somewhere it's bc human heads kept getting bigger (to support our big 'ol brain) not that the pelvis was too small to start."
terabytes27 also replied:
"Combination of both. Pelvis adapted to accommodate us going bipedal. Evolution-wise, the advantages of being bipedal were greater than complications during childbirth."
And the pelvis can't just get wider, because the internal organs would fall out. Even now some women have to deal with prolapses of pelvic structures, like the uterus
"We've evolved for millions of years with the sun always being there. Yet we get burnt and skin cancer from too much exposure. Dark skinned people are slightly better designed than the fair skinned ones."
Even dark-skinned people can get melanoma; it killed Bob Marley. Basal & squamos seem to be the real "white man's burden". But light skin is a *very* recent evolutionary development.
User No 1 said:
"Still craving sugar when you're already fat."
Silkkiuikku replied:
"This makes sense from an evolutionary point of view. Historically, starving to death has been much more common than being obese. So it makes sense to store as much fat as possible, because that fat may allow you to survive a famine."
Also sugar is addicting and being obese can make you resistant to the hormone that controls satiety (if I remember correctly)
"Having the CDKN2A and p14ARF genes overlapping at the exact same locus. This way, if one of them mutates or gets deleted, the other one does too.
As both of them protect us from cancer, if that happens you lose two cancer defenses at once, which is f***ing st***d."
drygnfyre said:
"Unable to regenerate body parts. You lose an arm or a leg, you can't grow a new one. We can grow hair and nails forever, but not body parts."
Cold-dead-heart replied:
"We go bald over time and if you damage the wrong bit your nails won’t regrow."
oliwoggle said:
"In our eyes, the blood vessels supplying our photoreceptors are in front of them and therefore in the way of the incoming light.
Probably not the biggest and there are some good justifications for it being set up this way. But it still must be such a pain for the brain constantly having to edit these out when forming our visual experience."
Relative-Hour-9359 replied:
"It's amazing how much the brain alters what our eyes actually see. Kinda worrying."
atmel9077 also replied:
"The brain basically has to upscale 480p to 4K. In order to do that it analyses the visual scene and reconstructs it. This is why when you misread a word, you didn't just read it wrong, you actually see it wrong.
Someone couldn't figure out how to build a decent camera but somehow managed to put a supercomputer next to it.
I would guess it's easier to have small eyes and a big brain rather than big eyes and a small brain, this way the eyes can move faster and are less fragile and less susceptible to damage."
"Having something as pressure sensitive as the testicles being in a sack on the outside of a man's body."
It's because to create sperms, the temperature needs to be a few degrees less than the body temperature. Which is achieved outside the body
KARAZINUS26 said:
"Digestive system, regenerative system, immune system. isn't it funny how human body can be fully created in 9 month but a broken ankle will take several years and never fully recover?"
Cold-dead-heart replied:
"To be fair, a human body takes around 20 years to develop. But yes, it’s always open to damage it can’t recover from."
Yeah but that thing we create in 9 months is rather small, to be honest
Frito_Pendejo_ said:
"The design of the knee:
We have 2 of the largest bones in our body and we need to connect them and have them rotate one way. Let's brainstorm!!
Let's put 2 ligaments on the outside and just for kicks, put 2 more INSIDE and cross them.
OK but how do we keep it from going the wrong way??
I know!! Let's put ANOTHER bone on the outside to stop it from bending backward and we will use 2 tendons to secure that in place.
BRILLIANT!!!!"
Autocthon replied:
"Anatomy is iterative.
Also kneeling would be a lot more uncomfortable without that bony plate in the front. And it doubles as a useful weapon in close combat. Which is important when you have a fairly limited number of natural weapons."
Yuppers, torn every single one multiple times until they are severed, nothing like being able to rotate foot °180 and get stuck. No insurance so it's been like that for 25 years
"IMO the whole “we put food into the only air hole we have and can choke and die if we aren’t careful” thing is a pretty big miss."
Appropriate_Gas_3802 said:
"I have autoimmune disease. St***d thing it's hurting it's own body."
Smart-Top3593 replied:
"This is what I was going to say. Allergies and all of the things that your body does TO ITSELF!!"
And BP censors don't care if you're dumb, but you can't be stupid without offending the dumb.
"That a tiny blood clot can kill you at literally any second. And oh yeah anxiety."
deluxejoe said:
"The eyes often suck and need an external lens to be useful."
Eelismon replied:
"Well for example a dog could also have equally flawed eyesight but we wouldn't know of it because:
1. Dogs can't read so they don't need a good eyesight
2. Dogs don't complain about being unable to read.
**I didn't mean to criticize or anything. I just brought up the idea that bad eyesight wasn't cripplingly bad until we learned to write. After that, it can and indeed is considered a major and crippling flaw."
As someone who is MASSIVELY short sighted and astigmatism in both eyes - reading is NOT the problem!?!? Without glasses/contact lenses everything I see is blurry, lights look weird, in a situation where I was in danger, without corrective lenses I am literally a sitting duck. Eyes are for more than reading you dingbat
"The appendix."
Jibber_Fight said:
"A stroke. My aunt had one when she was 31 and the healthiest person in the world. Ran an aerobics class at the Y, just perfect perfect health. Went to Pizza Hut with her the night before, next day, a massive stroke, and almost died, critical surgery, twenty years later she still has trouble speaking. It sucks. There is no reason that should’ve happened. A perfectly healthy person is damaged for the rest of her life. She’s still amazing and lovely and my favorite person but damn is that annoying."
ketra1504 replied:
"It is true. A stroke basically ruined the life of my grandmothers friend. One day she went from a happy and healthy person to one who has to be in a special institution because she can't function on her own, has half her body not responding to basically anything, cannot speak and is extremely frustrated to the point of being violent."
That's the blood clot from the former post when it reaches your brain
"The fact the brain can not regenerate more cells, but practically everything else can. Even though the brain is the most important."
The brain is a badass in delegating tasks to different parts of the brain if needed, though.
oppapoocow said:
"Rashes... it itches and makes it soothing when you scratch it, but scratching it makes it worse!"
ketra1504 replied:
"My professor once told me why you need to be extremely careful when handling epoxy resin thinners. You can safely assume that everyone is allergic to them and if it comes into contact with your skin it gives you the most horrible rash imaginable, another thing is that washing the rash with warm water feels almost orgasmic the hotter the water is and you have to be very careful not to burn your hands with boiling water. The rash also stays for around a week."
I have contact dermititis and it f*****g sucks...i look at a resin wrong and I get a rash
"Some things take far too long to heal and some things don’t."
"'Nostalgia is the greatest human weakness. Second only to the neck...' - Dwight Schrute"
"Our teeth don't grow back like Shark's do."
The Rise Of Mammals does a really good job explaining this! Basically, one of the great innovations of mammals was the development of teeth with opposing surfaces, for maximum chewing efficiency. Sharks can loose teeth and replace them constantly because they don't chew, they just grab and rip, so it doesn't matter how their teeth meet up. If a human's molars did that, our regrowing teeth wouldn't contact each other the way they need to for us to eat. Elephants do a kind of conveyor belt where only a few of their massive teeth are in their jaw at a time, moving forward as they wear down and eventually falling out to make room for the next set, but once they wear out their last teeth, they die shortly after. Grass-eaters like horses usually have extremely tall hypsodont teeth that gradually erupt out of the gums as the top wears away. And rodents have their always growing incisors. But with mammals, once they actually lose an adult tooth, it's gone.
spit_in_my_eye said:
"The laryngeal nerve that needs only travel a few inches from the brain to the larynx, but goes a long way around under the aortic arch instead. And our sinuses draining upside down."
Chastethrow316420 said:
"The sleep cycle."
WirelessTrees replied:
"Must sleep for a minimum of 8 hours of the 24 per day, and any deviation can lead to exhaustion, even getting more sleep leads to exhaustion. Why??"
Redditor also replied:
"I'm on a weird 12/32 sleep cycle. I'm just slightly off, but because the world doesn't work around that schedule, I effectively have one of the most brutal cases of insomnia of anyone I know."
I am a weird one that functions best when I get 6 hours and can't sleep more no matter what, can even split it up to 2 three hour sessions and be fine
"Eyelashes, designed to keep things out of your eyes but they just fall in anyway."
"The human knee. It is a nightmare of an engineering kludge.
Two rods, the upper and lower legs, balancing on top of each other, supporting the entire weight of the human body. And the only thing that keeps them from bending backwards? A tiny, free-floating thin half-dome of bone not attached to anything at all. And what keeps them from collapsing entirely? A mass of unhealing cartilage and some muscle fibers.
8 pounds (!) of precise force can snap the knee from the side, permanently crippling a person.
It is a ridiculously fragile, slapdash evolutionary kludge of the sort that could only be selected for in a species expected to live no longer than about 25 years.
Only - humans live a lot longer than just 25 years now, but the knee has never changed."
The maximum lifespan for a human tops out at around 125 years under ideal conditions, and that figure hasn't moved much since the Stone Age. The reason we have this narrative about people not living past 25 is because of the confusion with average life expectancy at birth, which includes high infant mortality and childhood deaths into the average.
Lootto said:
"You can close your eyes when it's time to sleep but you can't close your ears. I know it's evolutions way to make sure you wake up instead of just sleep trough any dangers around you, but still. Imagine how convenient it would be to just close your ears."
_goflyakite_ replied:
"So when your newborn is crying it's head off you can ignore it and sleep on."
But you can't smell anything while you sleep so burn to death...if we are made in gods image, God is f*****g stupid
"Being able to sit down on your own balls if you're a dude."
"That your chest f***in hurts when you think about someone too much.
S**t’s making me nauseous, yo."
"That there is a completely unprotected artery in your neck that if cut will kill you in a couple minutes."
Half of these are oversimplifications and assumptions from little knowledge. The human body isn't perfect but it's so damn impressive I could write an essay just from the knowledge I learnt from high school.
Half of these are oversimplifications and assumptions from little knowledge. The human body isn't perfect but it's so damn impressive I could write an essay just from the knowledge I learnt from high school.