We've all heard expressions and stats that just seem to "make sense," so we don't bother to check them out. It turns out there are a lot of misconceptions floating around. We're here to break down a few examples of what we like to call "B.S." That's...Bad Science!
Myth: Humans Use Only 10% of Our Brains
Myth: Clouds are Weightless
Myth: Sunshine is Yellow
Myth: You Should Drink 8 Glasses of Water a Day
This is more about using a one-size-fits-all rule of thumb than it is a hardcore myth. The fact is, almost everything we eat and drink contains some amount of water that helps hydrate our bodies, so you can stop worrying. According to a New York Times article by pediatrician Aaron E. Carroll, the persistence of this myth in spite of the lack of scientific evidence is remarkable given the number of studies that have shown otherwise. There are several possible sources of this popular myth; often readers have paid attention only to the first part of a recommendation (e.g., "2 liters of water per day") and ignored the second half (e.g., "most of which comes from food"). In any case, unless your doctor specifically tells you to, you can stop worrying about counting your daily ounces.
Myth: Gum Takes 7 Years To Digest
Have you ever been told not to swallow your gum because it will stay in your stomach for years? While this bit of folklore has been around for decades, it's simply not true. Although many of the ingredients in gum are not digestible (which is why gum doesn't just dissolve when you chew it), they just pass through your system like anything else (ahem, corn), and are usually gone within a few days. That's not to say you should swallow your gum -- if you're in the habit of eating other foreign objects while chewing: this Scientific American article cites a Pediatrics case study about a small child who swallowed lots of coins along with her gum, and the whole wad got stuck in her esophagus. So go ahead and swallow your gum if you want, just don't do it while eating pennies. Or rocks.
Myth: Camels Store Water in Their Humps
Actually, camels’ humps store fat, not water, according to the Library of Congress website. Camels rely upon that fat for nourishment when food is scarce, such as on a long trek through the desert. As the fat is depleted, a camel’s hump will become limp, and actually droop toward the ground. Once the camel starts eating again and gets sufficient rest, the hump gradually will fill up again and return to its normal look. When it comes to water, though, camels can go for long periods without drinking. That’s because when they have the opportunity, they drink huge amounts—up to 20 gallons at a time--and their because bodies use water super-efficiently and have a high tolerance for dehydration. According to a 1958 scientific journal article, one camel survived 17 days in direct summer sun without drinking water, and eventually recovered without ill effects. A human, in contrast, would have perished on the second day.
Myth: Dogs Have Cleaner Mouths Than Humans
Okay, admit it. You often let your dog give you a smooch on the face, or even the lips sometimes. And what’s the harm, you think, because after all, you’ve always heard that a dog’s mouth actually is cleaner than a human’s. The usual explanation is that canine saliva contains special chemicals that act as a sort of natural antiseptic, warding off infections. But as pediatricians Aaron E. Carroll and Dr. Rachel C. Vreeman explain in their book Don’t Swallow Your Gum: Myths, Half-Truths, and Outright Lies About Your Body and Health, all saliva—including human saliva—contains infection-fighting enzymes, and dogs’ drool isn’t special in that regard. And dogs don’t really have cleaner mouths, either. That misconception may stem from old studies showing that bites from human mouths were more likely to become infected than dog bites. But as doctors Carroll and Vreeman explain, one reason for that is that human mouths contain human bacteria, which is more likely to cause infections in people. In truth, dogs have more than 600 different types of bacteria in their mouths, according to the American Kennel Club’s website. That’s comparable to the 615-plus types that humans have.
Myth: Birds Will Die From Eating Wedding Rice
There’s a persistent urban myth that the celebratory custom of throwing rice at a bride after a wedding puts wild birds in danger, because the rice supposedly will expand inside the birds’ digestive tracts and cause them to explode. According to the science enthusiast website Live Science, the myth became more prominent in the 1980s, after a Connecticut legislator proposed a law banning rice throwing, and advice columnist Ann Landers published a letter from a bride-to-be who was concerned about the risk. While Landers later retracted her advice to avoid wedding rice for birds' safety, she seems to have forgotten and reprinted it nearly 10 years later. In 2002, however, University of Kentucky biology professor Jim Krupa had his undergraduate students test the myth, after discovering that nearly half of them believed it. They performed experiments in which they looked at the expansion rate of rice and the strength of the birds’ digestive tracks. The study, published in 2005, found that the only type of rice that possibly could pose a danger was instant rice, which isn’t usually tossed at brides. Subsequent research found that even instant rice grains didn’t harm wild birds.
If you'd like to learn more about Krupa's experiments, see (paywall) A Classroom Exercise for Testing Urban Myth: Does Wedding Rice Cause Birds To Explode or Were Ann Landers, Martha Stewart & Bart Simpson Wrong?
Myth: A Penny Dropped from the Empire State Building Will Kill You
You may heard somewhere that penny, tossed from the top of a tall building by a careless or malicious person, can become a lethal projectile by the time it reaches the ground. Rest assured, though, that when you’re walking around Philadelphia’s Center City district, you can feel free to look up and admire the sights without fear of that happening. As detailed in an article published in 2012 in Scientific American, University of Virginia physicist Louis Bloomfield did experiments in which he used wind tunnels and helium balloons to simulate what would happen if a penny was tossed from a skyscraper. As it turns out, the small, flat coin is cushioned by air resistance on the way down, so that it flutters to the ground the way a leaf would. If it did hit you in the head, you might feel a light impact, but that’s about it. If the air resistance somehow was miraculously eliminated, the penny would accelerate to a speed of slightly more than 200 miles per hour—which might cause some damage, but wouldn’t penetrate the hardness of your skull.
Myth: Peanuts are Nuts
Considering that there’s a "nut" in the word peanut, it’s easy to make the mistake of thinking that peanuts are nuts. Actually, the website of the Peanut Institute explains, peanuts don’t grow above-ground on trees the way that walnuts, almonds, and other true nuts do. Instead, peanuts -- along with beans and peas -- are legumes, which are edible seeds enclosed in pods. Peanuts are produced by plants that have green, oval-shaped leaves and yellow flowers and stand only about a foot-and-a-half in height. When the flowers are pollinated and lose their petals, the budding ovaries of peanut plants grow downward, and the peanuts develop under the ground. It takes about four to five months for peanuts to develop. But even though they’re not nuts in a biological sense, the Institute notes, peanuts are considered a nut for nutritional purposes. As such, the legumes actually are the most popular nut in the American diet, with peanuts and peanut butter amounting to about two-thirds of consumption.
Myth: House Flies Only Live For One Day
The common house fly, Musca domestica, which originated on the plains of central Asia, has adapted well to being around people, and feeds on our food and garbage, in addition to other even more disgusting stuff that we won’t get into. In addition to annoying us with their buzzing, though, house flies are a potential health threat, because they spread diseases ranging from dysentery to tuberculosis by picking up viruses, bacteria and other pathogens and transmit them to our things that we eat, according to the website of the University of Florida’s department of entomology and nematology. House flies can survive in climates ranging from tropical to temperate, and thrive in both urban and rural environments, so it’s pretty tough to avoid them. Maybe that’s why we like to console ourselves with the thought that they’re punished for the unpleasantness they cause with a tragically short lifespan of just a day. The problem is, though, that isn’t really the case. According to the World Health Organization, house flies typically live for two to three weeks, but in cooler climates, they can survive for as long as two to three months.
Stay tuned for more #BadScience myth-busting!