Popular beliefs

Cracking your knuckles has consequences, but not the ones you think

You’ve heard it before: Don’t swim after eating. You’ll lose most of your body heat through your head. Swallow a piece of gum, and it’ll stay in your body for years. Many of these common beliefs that parents or teachers have told you repeatedly over the decades are simply not true. Here are 10 everyday myths that science has set straight, and the real stories behind them.

The myth of carrots providing a better sense of vision in the dark became especially popular during World War II, when the British government promoted this idea to help explain the success of its pilots while keeping its new airborne radar technology a secret. It was just a myth, although there was a scientific explanation to back it up.

Carrots are rich in beta-carotene, which your body converts into vitamin A, an important nutrient for healthy vision. If someone is deficient in vitamin A, eating more of it can improve their eyesight. But for people who already get enough of the vitamin, extra carrots won't suddenly make it easier to see at night.

You hear footsteps in the middle of the night and find a family member quietly wandering through the house while asleep. Your first instinct is to wake them up, but remember you’ve been told it’s dangerous. That’s just a myth, so go ahead and wake them.

The person may be startled, confused, or briefly disoriented, but there’s no evidence that being awakened causes physical injury. The bigger concern is that someone suddenly pulled from sleep may react unpredictably or accidentally lash out because they don’t understand what’s happening. For that reason, sleep specialists usually recommend gently guiding the person back to bed if it’s safe to do so, rather than abruptly shaking them awake, but there’s no intricate danger to waking a sleepwalker.

Almost everyone has heard the sharp popping sound of someone cracking their knuckles, followed by another person saying, "Keep doing that, and you’ll get arthritis."

Researchers have been looking into that claim for decades, and the evidence simply doesn’t support it. The popping sound comes from tiny gas bubbles forming and collapsing inside the fluid that lubricates your joints, not from bones grinding together. Multiple studies comparing habitual knuckle crackers with people who never crack their knuckles have found no higher risk of developing arthritis. Some research has suggested that frequent knuckle cracking may slightly reduce grip strength or cause temporary swelling in a few people, but it has not been shown to damage the joints. So while the sound may bother the people around you, it isn’t likely to lead to arthritis.

Most of us have heard someone say, "Imagine what you could do if you used the other 90 percent of your brain." The truth is that modern brain imaging has shown that virtually every part of the brain has a purpose.

Even when you’re resting, different regions are constantly working together to control movement, memory, breathing, emotions, vision, and countless other functions. While not every area is active at the same moment, there is no large section of the brain sitting permanently unused. Scientists aren’t exactly sure where or how this myth started, but your brain is one of the busiest organs in your body. Even while you’re asleep, it’s hard at work keeping you alive and processing the day’s experiences.

If a child accidentally swallowed a piece of gum, some adult would inevitably claim it would sit in the stomach for the next seven years.

The warning, even if a myth, contains a small grain of truth. The gum base isn’t fully broken down by the digestive system the way other foods are. But that doesn’t mean it stays behind. Instead, it moves through your digestive tract along with everything else you eat and is naturally eliminated within a few days. So while swallowing pieces of gum isn’t something doctors recommend making a habit of, there’s no need to worry if it happens by accident.

After lunch at the lake or a backyard barbecue, the adults would insist everyone, especially the kids, stay out of the water for at least an hour. The idea was that digestion would pull blood away from your arms and legs, causing severe muscle cramps that could make you drown.

Medical research, however, has found no evidence that eating before swimming creates that kind of danger. While vigorous exercise immediately after a very large meal might make some people feel uncomfortable or sluggish, a normal swim after eating is generally considered safe for healthy individuals. The "wait an hour" rule probably prevented plenty of cannonballs during nap time over the years, but it wasn’t based on scientific evidence.

If you ever left the house on a cold winter morning without a hat, chances are someone reminded you to wear one since "most of your body heat escapes through your head." The belief became widespread after military studies conducted in the 1950s observed significant heat loss from uncovered heads. What they didn’t notice was that the subjects were bundled up everywhere else. Naturally, their only exposed body part lost the most heat.

In reality, your head loses heat at about the same rate as any other uncovered area of skin, depending on its size. A warm hat is still a smart idea on a cold day, but only because it covers exposed skin, not because your head has some special ability to leak away most of your body heat.

Many tongue illustrations show the tongue divided into neat sections, with one area for sweet foods, another for salty flavors, and others for sour and bitter. The famous "taste map" came from a misunderstanding of research published in the early 1900s.

While some parts of the tongue may be slightly more sensitive to certain flavors than others, taste buds across nearly the entire tongue can detect sweet, salty, sour, bitter, and umami, the savory taste found in foods like mushrooms, cheese, and broth. The old diagram appeared in textbooks for decades, making it one of the most successful scientific misconceptions ever taught in classrooms. Today, we know the tongue is much more versatile than that simple map suggested.

If you grew up in the age of bulky television sets, you may remember a parent telling you to back away from the screen before you damaged your eyes. That warning became especially common in the 1960s when early television models were found to emit unusually high levels of radiation because of a manufacturing defect. Those sets were quickly recalled, but the myth lingered long after the problem disappeared.

Modern televisions don’t pose that risk. Sitting very close to the screen may leave your eyes feeling tired or dry after a while, but it doesn’t cause permanent damage to your vision. Even if screen time is not recommended for children up until 7 years old, the screen itself isn’t likely to be the cause of poor eyesight.

Everyone learned about the five senses at some point: sight, hearing, smell, taste, and touch. That lesson dates back more than 2,000 years to the ancient Greek philosopher Aristotle.

However, modern science paints a much more intricate picture. In addition to the five traditional senses, your body constantly relies on other senses that work without you even noticing them. These include your sense of balance, your awareness of where your arms and legs are without looking, your ability to feel pain, temperature, and more. Depending on how they’re classified, scientists recognize anywhere between 10 and 20 different senses.

CULTURAL INFLUENCES

Konichiwa! Discover Ten English Words With Surprising Japanese Origins!

Image: David Edelstein

Japan, the "Land of the Rising Sun", is definitively a faraway land. While the past few decades have seen a surge in the integration between our two cultures, few languages seem to be as distant and at odds with English as Japanese is: After all, they have completely different writing systems, pronunciations, and sentence structures.

And yet, you might be surprised to learn how many words we use daily, come directly from the Japanese language. We have compiled ten of our favorite words ranging from logical loan words to surprising ones. Enjoy!

Image: Hunters Race

We’ll start with one of the most surprising entries on this list. What image comes to mind when you hear the word "tycoon"? Perhaps a 20th-century top-hat-wearing business magnate like Cornelius Vanderbilt, John D. Rockefeller, or even the Monopoly Guy (whose name is "Rich Uncle Pennybags", by the way). However, if the Japanese roots of tycoon are to be believed, this word refers to a different kind of leader.

In the 19th century, the Japanese shogun, the country’s leader at the time, opened business relations with the West. During his first government meeting, the American consul to Japan, mistakenly addressed the shogun by the title of taikun, a disused term that loosely translates to "great prince." In time, the word morphed into the "tycoon" spelling we now use, and by the 1920s it was commonly used to describe someone with great wealth and power.

Image: Clay Banks

The preferred resting place for every college student, futons are a comfortable and simple piece of furniture beloved by millions of Americans. Most futons are filled with cotton and are either used as a mattress directly on the floor or framed and used as a sofa or bed. While they might seem like an inexpensive way to decorate an apartment, in Japan futons are a centuries-old tradition that is still maintained by millions of Japanese households.

A traditional Japanese futon consists of a foldable mattress and a duvet, which are both flexible enough to be able to be stored away in a closet during the day. In the 80s, American futons started becoming increasingly popular, although they presented a key difference: most presented a wooden frame, that allowed the mattress to also be folded into a sofa.

Image: rishi

If you ever visited New York City, you have probably seen more than a few rickshaws (or as they are known in America, pedicabs) swiftly dodging traffic and diligently carrying tourists throughout the many streets of the Big Apple. And while most U.S. states have at least one city in which pedicabs are prominent, this environmentally conscious mode of transportation first gained traction in New York City during the '60s.

Interestingly, the word "rickshaw" comes from the Japanese word jinrikisha, which literally translates to "human-powered vehicle". The origins of the rickshaw are still debated, but most sources indicate that it was invented in Japan during the 19th century.

Image: Pablo Zuchero

This one is slightly controversial since the origins of this popular expression are still unknown. However, one of the most accepted theories indicates that at least half of this expression comes from Japan, or at least from American sailors trying to communicate in Japanese.

The "hunky" part of this expression comes from the Dutch word hunk, which means "home". By the 19th century, the adjective hunky had migrated into English, meaning "all right" or "safe". While the reason why this word was partnered with "dory" to form this expression remains a mystery, some believe that it comes from the Japanese word dori, which translates to road. This theory states that American sailors looking for places on which to have a drink combined hunky (which could also be interpreted as "satisfactory") and dori.

Image: Markus Winkler

The universal language of the internet, emojis have been extremely popular since the emergence of the online era. These symbols, first known as "emoticons" in the 80s, were comprised of cleverly placed keyboard characters. By the 1990s and early 2000s, the first specially crafted images for online messengers and cellphones were introduced, and their name quickly morphed into the now ubiquitous "emoji".

What’s surprising is how such a silly-sounding word as "emoji" can so perfectly describe what these little smiling pictures mean. It comes from the amalgamation of the Japanese word moji, meaning "letter" or "character", and the prefix e, which means "drawing" or "picture". Therefore, an emoji would literally mean a letter formed by a drawing, which perfectly encapsulates what an emoji actually is.

Image: Brooke Lark

Just like with "tycoon", the word "honcho" is sometimes used to describe a prominent boss or leader. While it might have fallen into disuse now, this word was insanely popular in the United States for a while. You might be surprised to know that this word not only comes from Japanese but that it is rather a fully-formed word that found its way from Japan into the American vocabulary.

By the time World War II was coming to an end, American war prisoners came back home after being held captive by the Japanese forces. They brought back the word honcho with them since it is commonly used in the military to refer to squad leaders. The 1950s are probably the time period in which the words "honcho" and "head honcho" were most popular. Famously, General Eisenhower was called the "chief honcho" by a prominent newspaper in 1952.

Image: Caroline Attwood

In American English, "Skosh" is a funny-sounding word used to describe a tiny amount. You can add a skosh more of salt to your food, you might feel a skosh tired after a long walk and you might ask someone to move a skosh to give you some more space on the couch. This word is sometimes spelled "skoosh", although this is far more popular in the United Kingdom.

Just like with "hunky-dory", skosh was brought back to the States by American soldiers after WWII. It comes from the Japanese word sukoshi, which translates to "a tiny or small amount". The earliest account of this word being used in English comes from 1952.

Image: Nikola Đuza

Karaoke might be one of Japan’s most iconic contributions to the world. Something is fascinating about how this form of entertainment combines the perfect dose of fun and personal embarrassment. It gives us both a safe space to make fun of ourselves, and a wonderful stage on which to perform our favorite songs.

While karaoke is definitively a loan word, it has found its way into every single English dictionary. It is definitively untranslatable: Karaoke is derived from the Japanese words kara (empty) and ōkesutora (orchestra). Curiously, this Japanese staple is so beloved by American culture that the United States holds the world record for the most people singing karaoke when over 160,000 people sang Garth Brooks’ "Friends in Low Places" in 2009.

Image: Sailko

Just like with karaoke, tsunami is a Japanese word that can’t really be translated. Well, it technically can be translated to "harbor wave" but let’s be honest: Tsunami has a way better ring to it. In English, this word is mostly used in a metaphorical sense, usually to describe a big and sudden influx. For instance, a restaurant could experience a tsunami of bad reviews, or someone facing a big decision could be met with a tsunami of advice.

While tsunamis are definitively a disheartening natural disaster, they have been featured in many pieces of Japanese art. Most famously, 19th-century Japanese artist Hokusai created an iconic woodprint called "The Great Wave off Kanagawa" depicting a tsunami, which is now synonymous with traditional Japanese culture.

Image: Vinicius Benedit

We’ll end this article with what’s probably the most beloved Japanese icon in modern times. Sushi has become an absolute staple in world cuisine, up to the point that you would have an insanely hard time finding a major city anywhere that doesn’t have at least a few sushi restaurants. The United States quickly embraced sushi since its rise in popularity in the 1960s, and it even introduced its own signature pieces like the California or Philadelphia rolls.

For such a simple word, sushi has a rather interesting etymology. It is mostly derived from the Japanese word su, which means vinegar. The meaning of the suffix shi is debated since no one really knows how it got attached to su to form the word sushi. However, some believe that shi might mean "to fix" or "to control", which makes sense considering how every sushi piece is meticulously crafted and arranged.