Dangerous truths

10 dangerously wrong beliefs—from lightning to antibiotics

Image: Lucian Alexe

We all think we know how the world works, but many "common sense" beliefs are flat-out wrong. From everyday health myths to misunderstood science, these misconceptions can mislead you, waste your time, or even put you at risk. Here are 10 things you are dangerously wrong about, backed by real facts.

Image: Michał Mancewicz

Contrary to popular belief, lightning can strike the same place more than once. Since lightning often targets tall, conductive structures, multiple strikes to the same location are not uncommon.

For example, the Empire State Building is hit an average of 23 times per year. The myth persists because rare events seem unique, but statistics show that repeated strikes are common, especially in high-risk areas.

Image: Roberto Sorin

Antibiotics target bacteria, not viruses. Using them for colds or the flu is ineffective and promotes antibiotic resistance.

Prolonged misuse can lead to resistant bacterial strains, making future infections harder to treat. Correct diagnosis is critical for proper treatment.

Image: Gavia

Bulls are actually color-blind to red. Their reactions in bullfighting are triggered by the movement of the cape, not its color.

The bright red (and similarly striking colors) was likely chosen to make the cape more visible to the human audience from a distance, enhancing the spectacle.

Image: Aman Krishna

Cold therapy offers temporary relief but doesn’t accelerate long-term muscle recovery. Overuse can impair adaptation to training.

Inflammation is part of muscle repair; blocking it too aggressively can reduce strength gains over time.

Image: Janosch Lino

Fluid needs vary by body size, activity, and climate. For some, eight glasses is excessive; for others, insufficient.

Relying strictly on this rule can cause dehydration or overhydration. Thirst and urine color are better indicators.

Image: Arturo Rivera

Even a single sunburn increases your lifetime risk of skin cancer, including melanoma. Peeling skin doesn’t undo DNA damage; it’s actually skin cells committing suicide to prevent the spread of harmful mutations.

Sunscreen, protective clothing, and shade are essential. Ignoring sun safety poses a serious health risk.

Image: Alexey Demidov

Waking a sleepwalker is safe. They may be disoriented or confused, but letting them roam unattended is far more dangerous.

The only real risk is injury from falls or collisions, not the act of waking them.

Image: Myriam Zilles

Fructose in fruit is healthier than processed sugar, but overconsumption still strains the liver and metabolism.

Even "natural" sugars can contribute to obesity, insulin resistance, and diabetes if intake is excessive.

Image: Kelly Sikkema

Sanitizers can’t safely remove all pathogens, especially dirt and chemicals. Washing with soap and water is always more effective.

Over-reliance on sanitizers can actually increase infection risk, particularly during gastrointestinal or respiratory outbreaks.

Image: Precious Plastic Melbourne

Mixing vinegar with bleach, hydrogen peroxide, or other cleaners can create chlorine or peracetic acid fumes—both highly toxic.

Even small amounts can irritate eyes, lungs, and skin. Believing vinegar universally "boosts" cleaning power is dangerous; always read labels and avoid mixing chemicals.

Decoding

Being a "treasured guest" is not a compliment. This is the hidden meaning

Have you ever heard "Code Adam" while shopping for groceries at Walmart? Or maybe you’ve heard how "Dr. Firestone" was being paged during a routine hospital visit. They sound like harmless announcements. But behind these ordinary words are secret codes staff use to signal emergencies without causing panic. From hospitals and supermarkets to airports and Disney Parks, these phrases quietly warn employees that something is happening. You hope you never hear them, but if you do, it helps to know exactly what they mean.

We all love getting special attention at airports or hotel desks, but if you hear the clerk call you a "treasured guest," don’t feel so flattered. You may not be as VIP as one could think.

In the hospitality industry, "treasured guest" has become a humorous bit of industry folklore to describe someone causing trouble. Maybe a customer yelling at staff over expired coupons, demanding impossible accommodations, or throwing a full-blown tantrum at the front desk. Whatever it is, the phrase has become the staff’s secret way to warn co-workers without escalating the situation in front of the customers. Most guests don’t realize the meaning, but once you know it, you may start hearing it more often. We just hope it’s not about you.

Imagine you’re pushing a shopping cart through Walmart when suddenly the overhead speaker announces, "Code Adam." You can easily assume it’s some kind of employee meeting or cleanup request. But when you see them start locking the exits and moving around, you know something’s wrong.

This code was created in 1994 by Walmart in collaboration with the National Center for Missing & Exploited Children (NCMEC), in memory of the tragic case of 6-year-old Adam Walsh. Adam was abducted from a Sears department store in 1981 while shopping with his mother. His father, John Walsh, later became famous for hosting the TV program America’s Most Wanted and advocating for missing children. Even if Adam’s story ended in tragedy, Walmart created the emergency system in Adam’s memory, and other retailers soon adopted it nationwide, intending to have a quick response to missing or abducted children.

You’re sitting in a hospital waiting room during a routine check-up when you suddenly hear "Code Blue, Room 214." Most people immediately know it sounds serious, even if they are not entirely sure why.

The phrase "Code Blue" is used at hospitals to draw the necessary staff and equipment to perform a resuscitation. It was created in the early 1960s at Beathany Medical Center by Dr. Hughes Day. Before then, hospital resuscitations were often chaotic and poorly coordinated. In 1961, Dr. Day received a grant to build one of America’s first cardiac care centers, and he developed both the Code Blue alert system and the modern crash cart to improve survival rates during cardiac emergencies. Today, the system is used in hospitals across the country, sometimes with specialized versions like "Code Blue Pediatric" or "Code Blue Neonate."

Imagine visiting a loved one in the hospital when the intercom calmly announces, "Paging Dr. Firectone to the third floor." Your head surely goes, "Dr. Firestone’s probably having a busy day up there." He is, but it’s not what you think.

The phrase is actually a discreet fire alert used to warn staff about smoke, flames, or overheating equipment without frightening patients and visitors. Hospitals adopted these coded announcements after realizing that openly yelling "fire" over loudspeakers could create panic, especially among patients who aren’t able to move quickly. "Code Red" is an alternative used by many health centers today, but it also hints at the situation while keeping hallways calm.

You’re standing at a checkout counter when the cashier picks up the phone and quietly says, "I need a Code 10 authorization." If you think that’s just another way to get a supervisor’s approval or technical issue, think again. In reality, the cashier may suspect the credit card is stolen or fraudulent.

Code 10 was developed through a cooperative effort between major credit card companies like Visa and Mastercard, along with international standard organizations. As credit cards became more common in the 1960s and 1970s, stores needed a discreet way to alert banks about suspicious activity without directly accusing customers and potentially putting employees at danger. When a cashier requests a Code 10, the bank’s operator begins asking yes-or-no questions to assess the situation and guide the employee on what to do next.

You’ve probably experienced those long airport security lines. The wait is usually uneventful. But sometimes, you can hear "Code Bravo" over the speakers. Maybe it’s a delay, or maybe it’s an issue with luggage. Within seconds, people stop moving, the security line freezes, and exits may even close. It’s something bigger.

Code Bravo is the emergency phrase used by airport security and the Transportation Security Administration to signal a serious security threat, such as an unattended bag, a breach at a checkpoint, or someone slipping into a restricted area. The term comes from the international phonetic alphabet used in aviation and military communications, where "Bravo" represents the letter B. When this is called, security staff immediately lock down affected areas, stop screening lines, and search for the source of the threat. To passengers, it’s sudden and confusing, but to security, it’s a carefully rehearsed response.

You are heading back to your cabin on a cruise ship when the speakers announce, "Code Alpha, Deck 7." You may think Alpha is related to the captain, but that’s not the case. It means someone on board is suffering a medical emergency.

The phrase comes from the NATO phonetic alphabet, where "Alpha" represents the letter A. In maritime emergency jargon, it became shorthand for a Priority A medical situation requiring immediate response. Cruise lines such as Royal Caribbean and Disney Cruise Line commonly use the term, though some ships use variations like repeating "Alpha" three times. Once the code is announced, onboard medical teams rush toward the specified deck or cabin. If necessary, stretcher crews are mobilized, and in severe cases, the ship may even divert course toward the nearest port for emergency evacuation. Passengers are enjoying the views, but the staff is running to save a life.

Anyone who remembers the CB radio craze of the 1970s probably smiles when they hear "10-4." Movies, truckers, and radio fans turned those number codes into a part of American culture. So if you overhear "10-33" on a police scanner, you might assume it’s just another routine message. But it’s not as simple as it sounds.

The 10-code system was first created in 1937 by Illinois State Police communications director Charles Hopper and later standardized by the Association of Public Safety Communications Officials, better known as APCO. Officers needed short phrases they could understand clearly over crackling radio signals. The 10-33 code commonly means an officer needs emergency assistance. In some departments, it also signals radio silence so dispatchers can focus on the crisis unfolding in real time.

Disney World is amazing, the parks offer something for everyone, and there are things to see wherever you look. But that’s exactly the kind of place where a child can easily disappear into a sea of strollers, balloons, characters, and crowds. For that reason, Disney has developed the "Signal 70," which alerts cast members and security that a child has become separated from their family.

The number comes from older police and emergency radio systems, where "70" was commonly associated with missing persons. Disney adopted the phrase because it allows employees to communicate discreetly without frightening or alarming nearby guests. If a member finds the child, they gently -and magically- escort them to Baby Care Center, where they coordinate the reunion.

Cruises are great to relax, enjoying a good book under the sun with a nice drink by the side. Until you hear "Echo, echo, echo" on the speakers. If you do, something is happening somewhere else on the ship.

The code is used among cruise employees to signal that dangerous winds or a navigational hazard are affecting the ship. It comes from the international maritime phonetic alphabet, where "Echo" stands for the letter E. In maritime signalling, the letter traditionally means "I am altering my course to starboard." And, in time, the phrase became associated with urgent ship maneuvers and weather-related warnings. However urgent, the repetition of the word by three doesn’t represent life-threatening situations. It alerts the crew of a certain hazard to prepare while avoiding panic among passengers.