From swimming after eating, to getting sick from sitting in a draft, we’re all told myths about what’s good or bad for us.
“I honestly beleave it iz better tew know nothing than two know what ain’t so,” wrote the 19th-century journalist and humourist Josh Billings, in his deliberately eccentric spelling.
The sentiment was repeated often, and eventually became an aphorism apocryphally attributed to Mark Twain: “It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so.”
Here, then, in no particular order, is a list of 10 household myths that may have been drummed into you as a child. All of them are false, mostly false, or misleading.
1. Swimming after eating is dangerous
A 1911 Boy Scouts book warned: “Many boys make the mistake of going into the water too soon after eating.”
I was certainly taught that. The logic was that being satiated diverts blood from the extremities to the digestive system, which could lead to cramps, either of the extremities or of the stomach, which could make swimming difficult, which could lead to drowning.
That’s not true. Let me quote the American Red Cross: “There is little recently published scientific literature or even general information on the effects of eating before swimming or swimming after eating. Several studies were conducted in the 1960s that showed no effect on swimming performance and minimal side effects at several different time intervals after a meal. No major medical or safety organizations make any current recommendations to wait before swimming after eating. No reported cases of eating before swimming causing or contributing to fatal or non-fatal drowning are reported in any of the literature searched. Currently available information suggests that eating before swimming is not a contributing risk for drowning and can be dismissed as a myth.”
2. Cutting hair makes it grow faster
Cutting hair can remove split ends, and make your hair look tidier and fuller, but hair itself is dead keratin that grows only from the follicle. Nothing you do to the extremities of hair will make it grow faster at the base.
3. We eat eight spiders a year in our sleep
Arachnophobia is an evolutionary development in humans, so it’s understandable that people filed away a dubious piece of trivia published in The Guardian 25 years ago. It read: “The average human eats eight spiders in their lifetime after they crawl into their mouths in their sleep.”
The Guardian pilfered this factoid from an article distributed via email, ostensibly published in a magazine called PC Professional, which turned out not to exist, by someone named Lisa Birgit Holst, which is an anagram for “this is a big troll”.
Spiders aren’t stupid. They know they don’t want to be in the mouths of animals that could eat them. Most of us sleep with our mouths closed, anyway. While we probably ingest some spider bits in our food (since regulations generally set a low but non-zero limit to the amount of insect detritus that is permitted in food), there is no record of anyone ever swallowing a spider in their sleep.
4. Playing video games makes children violent
Moral busybodies routinely blame modern media for the wayward behaviour of the youth. Before video games, it was television. Before television, it was comic books. Before comic books, it was radio. Before radio, it was pulp novels.
A significant amount of research, such as this meta-analysis, also suggests that violent video games are associated with increased aggression among players.
However, much of this research is questionable, since it relies on aggression measures that are not necessarily reflected in real-world behaviour. Most of these studies don’t exclude other factors that could influence violent behaviour, and are not designed to demonstrate cause and effect.
The real-world data that does exist is simple: as the popularity of violent video games exploded since the mid-1990s, violent crime rates among youths have actually decreased.
One study notes that it would take 27 hours of game play per day to cause a noticeable increase in aggressive behaviour. Most kids don’t play video games that much.
5. The five second rule
We all know this one. You drop some food on the floor, and some wise mother figure will say as long as you pick it up quickly, it won’t be contaminated with bacteria.
It may be true that dropping food on the floor, in most circumstances, doesn’t immediately make it inedible. If a floor is fairly frequently cleaned, a bit of dirt likely won’t kill you.
However, actual scientists conducted actual science on the subject, and found that the floor surface and food type makes a much bigger difference than exposure time, and bacteria, if present on the floor, can contaminate food instantaneously.
6. The pull-out method
Movies, television shows and social media suggests that there is a widespread belief that pulling out before ejaculation can prevent the risk of pregnancy.
Besides the fact that riding bareback doesn’t help to prevent the transmission of infections, pulling out in time also has limited prophylactic benefits. According to people who study other people having sex, about one in five people who rely on the pull-out method still end up pregnant.
An 80% success rate is extremely low by comparison with any other means of contraception. If you want to be entirely sure, doubling up on prophylactic precautions – the pill plus a condom, for example – is wise. If you want to live dangerously, sure, try the pull-out method.
7. Eating carrots improves your eyesight
This one is mostly, but not entirely, false.
Carrots do contain beta-carotene, which is a precursor to Vitamin A, which in turn is necessary for the body to produce rhodopsin, a protein that is important for both low-light and colour vision. Vitamin A deficiency is a well-known cause of blindness in poor communities around the world.
In a person with an otherwise healthy, balanced diet, however, eating additional carrots will not improve eyesight.
The link, tenuous though it is, made it just plausible enough for the British air force to use it as propaganda.
During World War II, German pilots were amazed to discover British fighters in the air whenever they got even remotely close to Old Blighty’s shores. The crafty Brits spread the word that British pilots could spot incoming raids from miles away because of the superior eyesight produced by a diet full of carrots.
The truth was a military secret: Britain was using a newly-invented technology called radar.
8. Milk with rBST should be avoided
How many times have you heard that cattle treated with growth hormones produce contaminated dairy products that are unhealthy?
What seems like a widely accepted fact is, in fact, a myth.
Recombinant bovine somatotropin (rBST) is a synthetic version of the BST that occurs naturally in cows. In the 1970s, scientists discovered that dosing dairy cows with a little extra BST could significantly increase their milk production.
A commercial product was developed and tested for well over a decade, before the US Food and Drug Administration approved it for use.
Critics claimed it was unnatural, of lesser quality, and that it contributed to breast cancer in humans. None of this was true.
Naturalness is irrelevant. Arsenic, cyanide and botulism are natural.
The quality of milk from rBST-treated cows is not statistically different from that of milk from untreated cows.
And the cancer scare is based on slightly elevated levels of insulin-like growth factor 1 (IGF-1), although it would contribute less than 0.1% of the IGF-1 that the body naturally produces already. Such a small change cannot plausibly have the effect of increasing the risk of cancer.
9. Draughts, fans, or cold weather make you sick
This one is mostly false, but also complicated. No, going outside with wet hair won’t make you sick. Sitting in a draught won’t make you sick. Being cold in general won’t make you sick, directly.
Colds and flus are caused by viruses. The viruses make you sick, not the temperature. In the absence of virus particles, no amount of cold weather will cause a cold or a flu (though it could cause hypothermia and frostbite).
Indirectly, however, there are reasons for the association between cold temperatures and viral illnesses.
The most obvious and probably the most significant reason is that when it’s cold, people tend to gather indoors with the doors and windows shut. Viruses spread particularly well in unventilated indoor spaces. (I recall reading that 97.5% of all SARS-CoV-2 transmissions occurred indoors, which is why the ban on outdoor recreation was so absurd).
Viruses responsible for many colds and flus, including rhinoviruses and some influenza viruses, prefer cooler conditions. This isn’t a universal rule, but it could be a reason why they seem more prevalent in cooler seasons and cooler climates.
There is also some research that suggests that the immune system functions better at core body temperature rather than the slightly lower peripheral temperature in the nasal cavity. Rhinoviruses that target the mucous membranes in the nose, therefore, may have a marginally easier time overcoming the body’s defences.
Generally speaking, then, cooler weather creates the conditions that make it easier for viruses to spread, and can make it harder for your body to fight off viruses.
That said, ventilating indoor spaces, even if it is cold, is likely to reduce your chances of catching the viruses that cause colds and flus, so by all means, crack that window and cause a draught. And if you go outside, with or without wet hair or that jumper your mom told you to wear, you’re actually in the best possible place to avoid airborne viruses.
10. MSG is unhealthy
Few chemicals have a worse reputation than monosodium glutamate (MSG), and few deserve their reputation less.
MSG has been used since the 19th century to add flavour to food. MSG has its origins in seaweed extract, which the Japanese have used forever to season bland rice-based dishes.
In the early 20th century, Kikunae Ikeda, a Japanese scientist, isolated it in the hope of making cheap, mass-produced food taste better, and so ward off malnutrition among the working masses.
Other products of this line of research? Beef broth (Bovril) and yeast extract (Marmite). What the scientists found was something called glutamic acid or glutamate, of which MSG is the most common salt.
It is found not only in seaweed, but also in such tasty treats as soy sauce, anchovies, parmesan cheese, tomatoes, mushrooms, meat, walnuts and asparagus. In fact, a typical consumer will ingest 13g of MSG daily from natural sources, and a mere 0.5g from food additives.
Glutamate is responsible for the fifth commonly identified taste sensation, in addition to sweet, salty, sour and bitter. The Japanese call it “umami”, or “the good taste”. We might call it “savoury”.
In 1968, however, one Dr. Robert Ho Man Kwok wrote a letter to the New England Journal of Medicine (NEJM), claiming that shortly after a meal at a Chinese restaurant, he experienced numbness at the back of the neck radiating down both arms and back, palpitations, and general weakness. He said he couldn’t be sure what caused his condition, which he dubbed “Chinese Restaurant Syndrome”, but MSG was one of the possibilities.
Since then, however, MSG has been blamed, entirely anecdotally, for a dizzying array of vague and general symptoms, including headaches; flushing; sweating; face pressure or tightness; numbness, tingling or burning in the face, neck and other areas; quick, fluttering heartbeats; chest pain; nausea; and weakness.
Some studies in animals have found possible associations between MSG and various symptoms, but more recent research points out that negative effects were only detected after giving lab animals extremely high doses of MSG that no human could ever consume.
Unless you’re allergic to MSG (which very few people are and which you’d know by allergies to foods that naturally contain glutamate), there is no reason to believe modest MSG consumption is at all bad for you.
Sixty-six years later, there are still calls for the NEJM to redress the false and racist legacy of their “Chinese Restaurant Syndrome” article.
As a taste enhancer, MSG often replaces salt and fats. There are good reasons to believe that both salt and fats, when consumed to excess, can pose health risks.
So here we have a traditional seaweed extract. It occurs naturally in many tasty foods. It has been extensively researched, but has not been found unsafe to consume in normal amounts. It helps make bland but nutritious food taste better. It cuts down on fat and salt intake.
I can’t imagine a better health food than MSG.
Stay tuned
That’s probably enough for one column. There are plenty more myths on my to-do list, so look out for future articles that tackle some more of them.
Stay skeptical, and keep pointing out myths that people uncritically accept as true just because their parents or grandparents told them so.
[Image: Carrots.webp – Propaganda published during World War II created the impression that carrots could improve night vision. Images: public domain.]
The views of the writer are not necessarily the views of the Daily Friend or the IRR.
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