[There's a competition involved! Find the bonus item at the end for more details.]
At Mytour, we’re no strangers to persistent myths that just won’t die. We’re constantly debunking them! From the infamous five-second rule to the false belief that bats are blind, these misconceptions have spread worldwide, despite being completely disproven. It’s not that people are unintelligent, it’s just that most of us don’t bother researching until something personally impacts us. It's a pattern we see time and time again, especially in political discussions—often it’s simply easier to stay uninformed and mutter ‘Ok boomer’ instead.
While most myths are just harmless misunderstandings that we never bother to correct, some have more sinister origins. Many commonly accepted 'facts' exist because of targeted campaigns by advertisers and big corporations, with little to no scientific backing.
While Sigmund Freud was absorbed with exploring women's penis envy, his perhaps less altruistic nephew, Edward Bernays, was busy devising ways for impersonal corporations to get their hands on your hard-earned cash— all with your consent. So, here are ten widespread myths that owe their existence entirely to those who profit off them. Each entry also includes a fun related video—perfect for a weekend watch.
10. Diamonds

Diamonds have long been hailed as a woman’s ultimate companion, though we’ve never quite defined why. We’ve been told they are rare, and that scarcity contributes to their high demand and price, but this is misleading.
While diamonds are undeniably beautiful and serve important roles in various industries, they are not as rare as we’ve been led to believe. This misconception was carefully crafted through a decades-long advertising strategy by De Beers, which controls about 85% of the global diamond market. While diamonds were once scarce, the discovery of vast reserves in Africa during the colonial era changed that. With supply no longer an issue, demand would inevitably fall. Instead, De Beers and other key merchants formed a monopoly that successfully perpetuated the illusion of rarity, maintaining high prices and demand for years.
9. Sugar Vs. Fat

In 1968, Senator George McGovern, a Democratic representative from South Dakota and future presidential candidate, initiated the 'United States Senate Select Committee on Nutrition and Human Needs.' This committee, despite resistance from the American Medical Association, concluded that 'meat was bad, bread was good,' which ultimately set in motion the obesity crisis that plagues us today.
The McGovern report—an influential set of recommendations regarding public health and nutrition—declared that all fat was the leading cause of malnutrition. However, the sugar industry played a major role in shaping the conclusions of this report. They actively funded scientists and launched large advertising campaigns to shift the blame from sugar to fat. It’s safe to say it worked, as many people still believe fat is worse for us than sugar, despite recent studies contradicting that assumption. Thanks, sugar lobby.
8. Orange Juice Is Better

In America, breakfast often comes with a glass of orange juice, a tradition unique to the country. It’s frequently considered a healthier option than the fruit itself, and many even argue it’s superior. However, when you realize that no other nation shares this passion for orange juice, you begin to wonder what’s behind it.
The truth lies in advertising. The idea that orange juice is a better choice was popularized by a clever campaign from a copywriter working for the California Fruit Growers Exchange (later known as Sunkist) in the early 20th century. Faced with declining demand, the growers needed to boost orange sales. The catchy 'Drink an orange' slogan became a game changer. Before the 1920s, orange juice was virtually unknown in the U.S., but by the early 1930s, it became the second-most consumed beverage in the country.
7. Coca Cola And Santa

Coca-Cola has consistently made headlines for a multitude of reasons—from their enduring rivalry with Pepsi, which has resulted in some amusingly intense advertising, to their involvement in controversial activities such as funding death squads in South America. Yet, their most significant claim to fame is the belief that they created Santa Claus. According to the company—and the many who still hold this view—their campaigns from the 1930s are credited with shaping the image of Santa as we know him today.
In reality, Coca-Cola’s connection to the creation of Santa Claus is as tenuous as Nestlé's claim to have invented water. The modern-day figure of Santa is derived from a blend of historical figures, both mythical and real, and has undergone numerous transformations over the centuries, largely independent of Coca-Cola's influence. Furthermore, an image of a red-and-white clad Santa, looking much like the one we recognize today, was published in Harper's Weekly about 40 years before Coca-Cola's famous campaign.
6. Everything You Should Know About Teeth

If you follow the advice of 9 out of 10 dentists, as seen in countless ads, you’ll supposedly avoid cavities and dental issues. Surely, it’s a surefire science-backed solution, right?
In truth, we still don’t fully understand how to maintain perfect dental health. Despite flossing and brushing twice daily, it’s entirely possible to develop cavities just like those who neglect such practices. This isn't because dentistry is some kind of magic, but because there are numerous unknown factors that affect the health of our teeth.
Pharmaceutical companies, however, continue to assert that they have all the answers. The reality is that much of what we think we know about maintaining clean teeth, as portrayed in advertisements, is little more than an educated guess at best and, at worst, could be harmful to your dental health.
We continue to believe that vigorously brushing our teeth and scrubbing away the film that causes cavities helps reduce them, even though numerous studies show that the bacteria responsible for cavities primarily thrive in cracks and fissures. A balanced diet plays a far more significant role in dental health than the latest toothpastes or fancy brushing techniques (thanks again, Mr. McGovern, for messing up the sugar debate). Essentially, eating a large steak might not be any worse for your teeth than using all those so-called miracle toothpastes.
5. Casual Fridays

Wherever you work in the world, if you’re employed by a corporation, the likelihood is that you’re required to wear formal attire most of the week. That is, except for one day—the often-coveted Casual Friday. For many teams, this day is seen as a chance to relax within the typically strict corporate dress code, encouraging creativity and fostering an out-of-the-box mindset.
While there may be some merit to this idea, the true origin of Casual Fridays lies less in a corporate concern for employee well-being and more in an advertising campaign launched by Dockers in the 1990s.
In the past, casual wear was strictly forbidden in the workplace. However, Dockers, determined to promote their khaki pants to professionals, launched an extensive ad campaign advocating for casual wear at work. They even sent a 'Guide To Casual Business Wear' to around 25,000 HR managers, who eagerly adopted it, and persuaded the state government to implement it in state-run offices. This initiative proved successful, eventually leading to the establishment of Aloha Fridays—a term for Casual Fridays that became widespread in workplaces across America and, eventually, around the globe.
4. Coffee Is Bad

Depending on whom you ask and where you are, the alleged harmful effects of coffee can range from mild constipation to fatal consequences. Numerous bloggers and health 'experts' advise steering clear of it, claiming it causes a variety of health issues.
However, scientifically speaking, there is no evidence that coffee has any negative effects on health. In fact, emerging research on this globally loved beverage reveals that it actually offers several health benefits. The negative myths surrounding coffee can be traced back to anti-coffee ads by a beverage called Postum in the early 19th century. Postum attempted to market itself as an alternative to coffee, though its name and message failed to resonate. Despite its failure, the claims against coffee persisted and were passed down over the years.
3. Cold Beer Is Better

Across different parts of the world, various versions of this myth exist. One widely-held belief is that warm beer is an inferior form of cold beer—not just in terms of preference but also health and hygiene. Many people argue that cold beer is not only more flavorful but also more hygienic and beneficial to the body. This idea stems from the notion that higher temperatures are more conducive to bacterial growth. However, upon closer examination, it becomes evident that all beer is sterilized during production, regardless of whether it's warm or cold. No studies support the claim that cold beer has any significant difference from regular beer, other than its lower temperature.
The true reason why cold beer is so widely preferred (even when it's cold outside) is largely due to the relentless advertising by beer companies, which emphasize the perks of cold beer over its warmer counterpart. From claims about attracting more women to being better for beach volleyball, these advertisements are everywhere. Yet, the rationale behind this aggressive marketing remains unclear, especially since the promotion of cold beer seems to mainly target hot weather, rather than having a direct impact on their sales year-round.
2. Homeopathy

Despite the widespread belief in its efficacy, homeopathy has yet to be scientifically proven to work. One extensive Australian meta-study aimed to put the debate to rest by analyzing over 1,800 scientific papers on the topic. The conclusion was clear: homeopathy does not work. Nevertheless, a significant number of people worldwide, especially in the USA, still believe in its effectiveness. So, how can this persistent belief be explained?
The answer, as we've seen throughout this list, lies in advertising. Homeopathy continues to be viewed by many as a legitimate alternative to modern medicine due to the influence of TV commercials and targeted online ads. The reasons these ads are legally allowed to run are varied, including lax regulations on medical product advertising in certain regions (many countries, in fact, ban medical advertising altogether). Additionally, the high cost of conventional healthcare and factors such as low literacy rates and limited access to medicine in underserved areas contribute to the continued belief in homeopathy.
1. Leaded Petrol

Few examples illustrate the immense power and influence of the advertising industry like the case of leaded petrol. For much of the 20th century, it was sold as an environmentally-friendly alternative to unleaded petrol. Despite the growing awareness of its dangers and its eventual ban in most countries, it remained available for public consumption for an astonishingly long period.
If you're wondering how something as evidently harmful as lead could be promoted as a good thing, the answer lies in the same tactics used in many similar cases: paying government agencies for favorable reports and relying on the power of advertising.
Nearly all oil companies involved in the promotion of leaded petrol—due to its cheaper production and better performance—knew about its detrimental impact on public health, but this didn't deter them. They funded studies that presented leaded petrol as a superior choice, managed to get it legalized through lobbying, and sustained this perception through advertising so effectively that many older people still instinctively seek the 'leaded' sign at gas stations.
Thanks to Big Oil, lead has become an unavoidable part of cities worldwide, along with its lasting impact on public health—an effect we can never fully measure—even though it has been phased out in most countries in the past two decades or so.
It's truly astonishing what the media can convince people of these days. One list from the archives, '10 Insane Ways The Online Media Is Lying To You', explores other ways this manipulation is occurring right now.
+ Contest

It's been quite a while since we hosted a Mytour competition, and what better list to use as the basis for offering a prize than one about the dark side of advertising? The grand prize includes five $100 Amazon.com gift vouchers for the commenters with the most votes by 12:00am on Sunday the 10th (24 hours from the publication of this list). This should help kickstart your holiday shopping!
The rules are simple: your comment must be related to this list. Feel free to ask your friends to vote for you—each comment has a 'share' button, but your friends must be real people, not robots! Additionally, make sure to upvote comments you particularly like. Downvotes are not considered. Moderators and the author of this list are not eligible. Anyone can participate, no matter their country of origin. Best of luck! P.S.: I've hidden a few Easter eggs in this list. Can you find them?
