25 Popular Medical Myths Debunked

Are you ready to discover your college program?

Search Colleges
TheBestSchools.org is an advertising-supported site. Featured programs and school search results are for schools that compensate us. This compensation does not influence our school rankings, resource guides, or other information published on this site.

Continuing in our series on myths, there are many medical myths that scream for attention. Some myths are harmless fun, but many of these myths are downright dangerous. Medical myths can be as complex as the psuedosciences like phrenology (#24), or as simple as a food myth like "Coffee Dehydrates you" (#5) or "You shouldn't swim less than 30 mins after eating" (#4). Read on and see if you have fallen for any of these medical myths.

Forensic Myths

1. Truth Serum

There is no such thing as truth serum. There are, however, a number of ways to get intoxicated. And drunk people are known to speak unguarded honest truth if they are willing.

Since getting "smashed" or "wasted" reduces inhibitions, such people are more prone to say things they otherwise would not. There is a history of military, police, and clandestine services that have used Sodium Pentathol, Sodium Amytol, and Scopolomine with the hope of eliciting confessions or secrets from suspects. But the barbiturate effect of the drugs often made them so relaxed and pliable they'd tell the questioner whatever they want to hear.

“Truth serum” induced confessions, as such, are not legally admissable in court. And that's the truth. [Source]

2. One's Hair and Nails Continue to Grow After Death

fingernails-after-deathThis misunderstanding has an easy explanation. At death, the body begins to dehydrate. The moisture from the body gradually seeps out or dries up. The inner organs and skin shrivel and contract. It's like the skin is pulled back tight over the scalp, hands, and feet and this can give the appearance of continued growth of the nails and hair. They only appear to grow. In fact, they are not growing, unless you are a vampire. [Source]

3. Natural Blondes Are Going Extinct

blondQuick, mate with as many blondes as you can so we can “Save the Blondes!” No. don't do that. Blondes are not going extinct. A few details have been tied to this myth to make it sound plausible but it's still a myth. Some say men are more attracted to artificial blondes (“bottle blondes”), so they select mates who are bleached brunettes instead of natural blondes. Also, blonde hair is a recessive gene and supposedly, recessive genes are evolutionarily deprived. They're naturally inclined to exit the gene pool over time. Some even say that the World Health Organization (W.H.O.) first issued this report. But the W.H.O. did no such thing. Genes for blonde hair have always been recessive and there's been no measurable decline in blondes so far. If anything, the fact of “bottle blondes” testifies that blondes do have enough “fun” (Dating? Sex? Partnering? Marriage?) to where brunettes mimic that appearance. Meanwhile, men are liable to mate with women of all sorts of hair colored women. Bleach blondes and natural blondes are still collectively attractive in their own way so that there's no disadvantage whatsoever when it comes to baby-making. Anecdotally speaking, blonde hair, especially natural blond, is a commodity in places where blond hair is rare. That spells an evolutionary advantage; blond girls (or guys) are desirable to potential mates seeking someone with a striking or foreign appearance.

Food Myths

4. You'll cramp if you swim less than 30 minutes after eating

swim-crampUndoubtedly, a few people have experienced cramping in the pool or lake soon after eating. But the two don't seem to be related. More likely, alcohol was involved and drinking alcohol is known to cause cramping by dehydrating your body. Go ahead and finish your hoagie on the high dive, but you should save your beer for later.

5. Coffee Dehydrates you

coffee-dehydration-mythThe caffeine in coffee has a diarrheic effect and can raise your heart rate and energy level, hence you expend water. Water, by the way, is the chief conduit for all your metabolic processes, and it's a big part of your sweat. But coffee is also mostly water. Overall, coffee doesn't dehydrate you. Nevertheless, if you need fast effective hydration, it's hard to beat a tall glass of water. If you need fast energy, try shotgunning a Starbucks™ doubleshot.

6. Your Stomach Will Explode if you Eat Pop Rocks and Drink Soda at the Same Time

This one isn't even a little bit true. That famous candy, Pop Rocks™, does crackle and pop in your mouth and a stomach full of Pop Rocks and soda pop might give you indigestion but that's about it. According to legend, little Mikey from the iconic Life Cereal™ commercials, died of a pop rocks and soda overdose. Supposedly, his stomach exploded after he drank a six pack of Pepsi™ and six packs of pop rocks. That event never happened, and Mikey is alive and well. But even if someone tried this, the worst he'd get is a stomach ache and tooth decay.

7. The Average Human Ingests 8 Spiders a year

eating-spidersUnless you are on the caveman diet, this just doesn't happen. This myth says that people accidentally swallow spiders while sleeping. While we sleep with our mouths open, so the story goes, a dangling spider drops down on a line or crawls on over to investigate that warm cave (your throat). Woops! We swallow the curious little critter. The problem is that spiders don't do that. Spiders avoid humans since we give off a lot of vibrations—beating heart, breathing, moving—which signal “danger” to timid little spiders. They have every reason to avoid our lumbering landscape. We're so big and threatening, we don't represent any helpful target for them. That's why in scary movie scenes, when you see cob webs it signals a dead, abandoned place, devoid of human life. Spiders generally avoid contact with humans wherever they can. Now if you like the taste of spiders you can eat however many you want. But the rest of us need not fear accidental arachnid ingestion.

8. Chewing gum stays in your stomach for up to 7 years

Bubble-gum-mythYou should see a doctor if food or candy stays in your digestive tract for longer than 24 hours. It is true, however, that chewing-gum doesn't digest totally. But it will pass through your digestive system within 24 hours and no longer than 48 hours. If gum were to stay in there longer than that then it's constipation and that's not unique to gum. Now if you were to have a large wad of gum, perhaps, I don't know, because your fraternity brothers made you swallow 17 packs of gum to prove your loyalty to the frat, and that baseball-sized gummy wad is clogging up your "pipes", then maybe you can get your fraternity to pay for your surgery, and prove how loyal the frat is to its brothers. Meanwhile, normal amounts of chewing gum pose no real threat.

Contagion Myths

9. Eating Chocolate and Fried Foods Gives You Acne

Acne is common to teenagers, and teenagers are known to for their voracious appetites, including chocolate and fried foods. But other than that connection, there's no evidence that the two are related. Acne happens when the skin has too much of a waxy natural oil called sebum. Hormonal teenagers tend to have this problem, so some scientists think that hormones are the culprit but no one really knows just yet why teenagers get bad acne. Eating chocolate and fried foods can however circulate oils in the body and cause distention in the skin. It's called getting fat.

10. If you handle frogs or toads you will get warts

You may handle frogs or toads and you may get warts, but the two aren't normally connected. The wart-like lumps occasionally found on frogs aren't warts at all, they are glands. And amphibian glands aren't contagious. Warts are contagious though, but not like that. Warts are a viral infection transmitted by skin-contact, such as when broken skin or a wound comes in contact with the human papilloma virus. Common skin warts are from any of 100 different types of HPV. Frogs aren't particularly clean though. And there are a lot of germs and bacteria you can get if you handle frogs on a regular basis. So it's still a good idea to wash your hands regularly, whether you've been playing around with lumps of HPV or with a bunch of frogs.

11. You can catch an STD (Sexually Transmitted Disease) from a Toilet Seat or Bus Seat

Venereal diseases cannot live long outside of the body, and especially not on a cold hard toilet seat or bus seat. Some diseases can spread by skin to skin contact however like herpes, genital warts, and pubic lice (crabs). And some diseases like herpes, oral gonorrhea, and chlamydia can by caught from kissing (including deep kissing) since kissing can transfers saliva and trace amounts of blood. Now, bathrooms aren't exactly sanitary, especially handles and floors. But surprisingly, the toilet seat is the cleanest public thing in the bathroom. You could eat off of it, not that anyone in their right mind would do so.

Myths About Injuries and Inconveniences

12. Shaving causes hair to grow back thicker

shaving-mythThis myth seems to have arisen among women and pubescent boys; the women because they didn't want their body hair to grow back in thick stubble and the boys because they do want thick stubble. In fact, shaving or cutting the hair does nothing to thicken the individual hairs. Instead, the hair regrows at the same regular rate and shape each time. The hair may feel thick or tough when it's stubbly because it's still imbedded in the skin and less flexible than the portions of hair further removed from the follicle. Even if your leg hair is so tough you need a weed-eater, rest assured that shaving won't make it worse.

13. Your heart stops beating whenever you sneeze

heart-stop-sneezeSneezing seems to pause everything in your body, but not even a big sneeze can keep your heart from beating. The electrical signal telling your heart to beat works just fine while you are sneezing. Sneezing can however cause a momentary irregularity in your heartbeat since sneezing affects blood flow and that may be how this myth arose. Now, you can confidently say, even after a violent sneezing fit that "My heart will go on."

13. Your eyes will pop out if you sneeze with your eyes open

eyes-pop-out-sneezeSneezes can erupt at a speed of 200mph but eyes and nose aren't connected like that. That pressure won't affect your eye socket. The pressure can affect your nose, throat, sinuses, and lungs but your eyes are too secure in their eye sockets to go anywhere. If you don't believe me, you can test this myth too by sniffing inside a used vacuum cleaner bag till you start sneezing. But I wouldn't recommend it.

14. Brain cells don't regenerate

brain-cells-don't-regenerate Your body has a remarkable ability to regenerate cells. Every 30 days or so, your epidermis replaces every surface cell of your skin. Intestinal lining, and some "high use" areas can regenerate even faster. Other organs aren't as quick to reproduce. But, for whatever reason, the rumor has spread that brain cells don't regenerate. Perhaps this myth arose to scare rascally youth away from various brain-damaging revelries. It has been proven however, by Researchers at Cornell University, that brain cells do regenerate at least in the portion of the brain responsible for learning and memory: the hippocampus. Now the study only demonstrated regrowth in one portion of the brain. This breakthrough is no cause for drunken revelry.

15. Men Don't Get Breast Cancer

bra-cancer-mythThis myth suggests that men can't get breast cancer because they don't have breasts. It is true that men don't get breast cancer as often as women. However, men do have mammary glands and some are fairly developed due to a condition called gynecomastia. In rare cases, some men are even able to lactate. So men do have some breast tissue wherein breast cancer can occur. Almost 2,500 men in 2016 were diagnosed and almost 500 died from breast cancer. However, breast cancer is far less common among men than women (about 100 times less common) since women tend to have more developed mammary glands and more breast tissue. Women also tend to undergo more hormonal and physiological changes to their breast tissue in the course of their lives. Known risk factors for breast cancer include such gender-specific factors as early menstruation, certain oral contraceptives (birth control pills), late pregnancy (after age 30), non full-term pregnancy, estrogen replacement therapy, dense breasts, and post-menopausal obesity. [Source]

16. You shouldn't "lick your wounds"

dont-lick-woundsYou've probably done this before: thumbing through papers you accidentally cut your finger and instinctively you put your finger in your mouth. Why do we do this? Conventional wisdom says that the mouth is a dirty place and we wouldn't want all the bacteria from our mouth to infect that new cut. In this case, however, conventional wisdom is wrong and your instincts are correct. Sure the mouth has bacteria, but it also has saliva. And in your saliva there is a special protein called histatine which acts as a disinfectant and it boosts healing. That means, it does not just clean the wound, it speeds up the repair process too. For minor cuts, scrapes, and injuries it is a perfectly natural and helpful response to suck on it. But, to be fair, you should go on a "case by case" basis here. Histatine is not a miracle drug. It's fine to suck your hand or finger after a small cut, but that's probably not a good idea for large cuts, scabs, poison ivy, or any run-ins with a garbage disposal.

Folk Remedy Myths

17. Inner ear (“daith”) piercings cure migraines

Daith_PiercingThis one falls under the category of “questionable medicine.” Daith piercings puncture the hard cartilaginous nodule covering your ear canal. Supposedly, this brand of piercing helps reduce or eliminate migraines. This piercing treatment may sound more plausible alongside of acupuncture, another disputed form of alternative medicine. Both generate pain with a prick or puncture and both are thought to have medical benefits. However, there just isn't any reproducible, extensive, or otherwise well-demonstrated proof that this sort of piercing works to reduce migraines. The only evidence so far offered is anecdotal, and doesn't rule out the placebo effect. Perhaps in the future extensive testing will demonstrate some low-grade benefit here, but so far there's nothing of the sort. You'd do better to cancel your Piercing appointment and take an Advil. Daith piercings do correspond with ear pain, probably because they put a hole in your ear.

18. You Shouldn't Sleep After a Concussion

concussion-mythThere is some wisdom to this, but it's a bad general policy since sleep is the main way your body heals. This medical myth stems from a justified fear of comas. Most concussions are minor, can be treated at home (after a doctor's visit), and have little chance of major complications like a coma. Overzealous friends or family, can do a lot of harm if they don't allow the concussion victim to sleep. The fear is that if a person suffered a concussion, for example from a football injury, they think he shouldn't be allowed to sleep because he might slip into a coma and never wake up. The person may or may not be at risk of a coma, but that's why he needs to see a doctor immediately anyway. Otherwise, if we play doctor and do not allow him to sleep--when he's stable and well enough to sleep--we are denying him the chief means of recovery. Lack of sleep can worsen symptoms like sensitivity to light, lethargy, confusion, headaches, etc. Under a doctor's care, medical staff can evaluate whether he has internal bleeding, swelling, or any factors that might trigger a coma, in which case he can be checked in, observed, and treated. But even then, the doctor will allow him to sleep, while monitoring his vital signs, or waking him every so often. When the doctor determines he is stable and otherwise a low risk for a coma, normal concussion protocol includes lots of sleep.

19. Feed a cold and starve a fever

feed-feverColds and fevers dehydrate the body. Dehydration worsens when you refuse food or drink. Not to mention, your body's normal nutritional needs are met with food and drink. "Starving" a fever really starves the fevered body, when, instead, the body needs nourishment to fight whatever is causing the fever. It's fine to adjust the quantity and kinds of food and drink in your diet, as flu-like symptoms set it. Nausea or appetite loss might divert you from that Eel Sushi. Rather than ditching all fluids and nutrition to "starve" your fever, instead heighten your fluid intake for example, with chicken noodle soup and a cup of hot herbal tea. The fluids will fight dehydration, and the steam will open your nasal passages to help you breath better. The broth can help coat your throat like a cough drop. And tests have shown that chicken noodle soup slows down neutrophils, the white-blood cells responsible for upper respiratory symptoms. You can also sip some ginger ale to ease an upset stomach. There's still no "cure" for the common cold, but you can treat the symptoms (including fever). I find that reruns of X-Files help a lot too, but that's just me.
[Source, Source]

Psychology Myths

20. Schizophrenia is multiple personality disorder

multiple-personalityThose are two different disorders. The term schizophrenia does translate, literally, as “split-brain” but that refers to “a disruption between the usual balance of emotions and thinking” (Source: Mayo Clinic). Schizophrenics may experience a felt separation from reality, along with hallucinations, delusions, confused thinking and speech. It's a lifelong disorder. Meanwhile, multiple personality disorder—now termed dissociative identity disorder—is an extreme form of dissociation marked by a radical break on one's personality into two or more personalities. It can be lifelong, but with intensive therapy has been known to recede or disappear altogether. If the voices in your heard aren't yours, you're schizophrenic. If the voices in your head are yours, and yours, and yours, then you have multiple personality disorder.

21. Men think about sex every 7 seconds

men-sex-7-secondsThis statistic plays to our ignorance and low view of men. There are however actual pathological sex addicts whose focus on sex is so consuming and distracting they have lost the ability to function in life. Perhaps some of them achieve this ridiculously high rate of dirty thoughts. But according to a 2012 Ohio State study, the tested numbers are more like 1 to 388 times daily for men. That is 1 sexual thought every 223 to 86,400 seconds. That ranges from almost 4 minutes to 24 hours, on average. Men still think about sex more than women. For women it's up to 140 x's per day, compared to men, (up to) 388 times daily. This myth speaks to some truth, but it exaggerates that claim beyond reason. To be fair the testing methods in that 2012 study were fairly imprecise—participants were to keep personal record using “click-counters” and submit their totals at the end of the day. That study needs repeated findings from other studies to round out that research and verify their conclusion. Taken on its own, it proves very little, especially since the test subjects were all 18-25 years old. Um, methinks we have a biased sample. This “averaging” also gives the misleading impression that men are roving sex fiends who can't sustain a focused thought more than a few minutes. A better way to interpret this data, supposing that it's correct, is that men often concentrate for long periods on other things besides sex, but when they do think about sex it tends to be longer or include more distinct thoughts than it does for women. Either way, men might be prone to naughty thoughts but probably not every 7 seconds. Good grief!

22. You shouldn't wake sleepwalkers.

sleepwalkingThere's no great risk or harm in waking up a sleepwalker. The clinical condition of somnambulance, walking and talking (etc.) while sleeping occurs in stage 3 sleep; that's deep sleep. So it may be difficult to waken a sleepwalker. If you do wake them up they can be startled, disoriented, and agitated but there's no health risk there. Sleepwalkers are sometimes known to do dangerous things like try to cook or handle tools. In those cases, you should wake them up so they don't hurt themselves. The worst that will happen, if you wake a sleep walker, is that they get startled and they push or hit you on accident. The greater danger is that a sleepwalker trips down the stairs or leaves the stove on. Don't be afraid to rouse a sleepwalker, especially if it's going to be really funny.

23. Dipping people's hands In warm water, while they sleep, will make them wet the bed.

This practice will wet their hand, but not their bed. This myth was tested on Mythbusters and certifiably busted. It sounds plausible enough, but it just didn't seem to work, at least not on the adults tested. Perhaps this trick works well at preteen campouts, but then again, you can't tell if they were going to wet the bed anyway. Either way, it's best not to be caught sleeping in the presence of mischievous preteens.


24. Phrenology

L0001965 Phrenological organs, 1887 Credit: Wellcome Library, London. Wellcome Images images@wellcome.ac.uk http://wellcomeimages.org Phrenological organs, 1887 The human nature library. Published: July 1887 Copyrighted work available under Creative Commons Attribution only licence CC BY 4.0 http://creativecommons.org/licenses/by/4.0/
Phrenology is the study of the surface of the human head for the purpose of interpreting one's character and mental abilities. This is not merely interpreting happiness from one's wrinkle lines or brain damage according to head wounds. The theory of phrenology is more complex. First begun by Franz Joseph Gall in 1796, phrenology proposes that the human brain has regions corresponding to different virtues such that the shape of the brain both determines the shape of the skull and it points out different strengths and weaknesses in one's personality. Phrenology was quite popular in the 1800's, in large part because it was very flexible, hands-on, and could be made to support other popular movements at the time such as social evolution, scientific racism, or even eugenics. Where racism was popular, ethnic distinctions in skull shape could be matched with theories about racial superiority or inferiority, and the different "races" could be treated as different species of man in the course of human evolution. The more "white" one's features were, so the theory goes, the more one is prone to intelligence, moral fiber, and even material success. Phrenology played a big role in bolstering the societal push for eugenics (selective breeding for the purpose of improving humanity). In the U.S. several eugenics laws were passed, enabling the state to sterilize certain people deemed "feable-minded" or mentally "defective." In total, about 60,000 U.S. citizens were sterilized, many thinking they were getting an innocent flu shot. Of course, phrenology didn't cause those events. But phrenology was one of the main tools used to lend a scientific air to the idea that black people, poor people, or country-folks were "feable-minded" burdens to humanity. Eventually the eugenics laws were repealed (long after Nazis tried their hand at eugenics in World War II). Phrenology was likewise cast aside. As a "science" it lacked predictive power, failed testing, and was loaded with too many assumptions. Phrenology did however introduce at least one important idea for modern science, and neuropsychology in particular, that human personality somehow arises from features of the brain.

25. Four Humours/Humourism

four-humours-1152x1152The Four Humours Theory, a.k.a., Humorism, is a very old understanding of psychology, medicine, and nature. By this theory, everything in nature, including our personalities are organized around four elements: earth, air, water, and fire. The four personality types are (1) Melancholic—analytic and quiet, (2) Phlegmatic—relaxed and peaceful, (3) Choleric—short-tempered and irritable, and (4) Sanguine—optimistic and social.

Phlegmatic Sanguine Choleric
Humour: Black Bile Phlegm Yellow Bile Blood
Element Earth Water Fire Air
Season Winter Autumn Summer Spring
Life Stage Old Age Maturity Childhood Adolescence
Qualities Cold & Dry Cold & Moist Hot & Dry Hot & Moist
Organ Spleen Brain Gall Bladder Heart
Planet Saturn Moon Mars Jupiter
Now humourism is interesting, and insofar as it's used to help distinguish personality types it's at least a little helpful. Modern personality tests often use this naming system to identify common personality types: "He's choleric," or "She has a bit of melancholy." Disconnected from the larger worldview of humourism, the personality theory is a helpful contribution that's proven useful over many years. But it survives only as a "soft science," in the untestable and conjectural regions of pop psychology. But humuorism is not just a way to categorize temperaments; it ascribes elemental causes to those personalities, and mystically identifies personality with celestial bodies and seasonal changes. It wholly misinterprets bodily organs and fluids and it just can't stand up to the rigor and testing of modern science. It's important to remember that humorism predates chemistry, forensics, virology, genetics, modern anatomy and physiology, modern medicine, psychology and psychiatry, and modern science entire. When humourism was gaining ground in the time of Hippocrates (4th-5th century BCE), autopsies were not allowed, they would cremate bodies without examination. Humourism is an ancient effort to make sense of the world and, perhaps in its time, it was the best that (premodern) science could offer. But it has long since been discredited as a serious medical theory. Humourism has been laughed out of modern academia.

Take the next step towards your future with online learning.

Discover schools with the programs and courses you’re interested in, and start learning today.

Search Colleges
TheBestSchools.org is an advertising-supported site. Featured programs and school search results are for schools that compensate us. This compensation does not influence our school rankings, resource guides, or other information published on this site.
Woman working at desk