COMMON MEDICAL MYTHS THAT JUST WON'T GO AWAY

In the olden days they used to believe that cutting a vein and letting you bleed for an hour or two would cure all sorts of maladies, while as recently as the last century some experts still believed nicotine was good for the nerves. But don't laugh at our ignorant ancestors. We're just as guilty of believing medical myths, even when there isn't a shred of evidence to back them up.

From recommendations of drinking eight glasses of water a day to warnings about staying in from the cold when sick, some medical myths endure no matter how many times they've been disproved. Even doctors still believe some of them.

Here are 27 of the most common medical myths compiled from various sources. (Note: They are not in ranking order).

Myth 1: Starve a Fever and Feed a Cold

It will not help to lower your fever if you do not eat. In fact, limiting your food intake while you are sick hinders the healing process. Don't force yourself to eat if you don't feel good, but don't starve yourself if you're hungry and can't remember "which one lets you eat". It is very important that you maintain hydration by drinking a lot of liquids, as fever promotes the loss of fluids.

Myth 2: You Can Sweat Toxins Out of Your Body

Our sweat is the human body's cooling system. We would overheat and die within minutes without it. The things that strain toxins out of our bodies are the kidneys and the liver, and they do a hell of a job (thanks you guys! - and sorry about last weekend!). Fad exercises that make you sweat are just fads...or a way to lose water weight so you can pretend like you workouts are working better. 

Sweat contains water and trace minerals, and that's it. No toxins, no germs, no bad spirits. Just stinky water.

Myth 3: If you eat less food, your stomach will shrink

Those who are on a diet program are often advised by doctors to slow down on their food intake, for it is believed that in so doing, the stomach size will shrink. Don’t be fooled by this notion! The amount of food intake has nothing do to with the size of our digestive system, it will always maintain a constant volume throughout life. The only benefit of eating less is that it will help in weight loss.

Myth 4: Milk Generates Mucus

In a study of 330 patients, nearly two out of three believed milk increases phlegm production. But it's not true. In one experiment, volunteers were infected with the cold virus, and some of them drank a lot of milk as well. The weight of the nasal secretions did not increase in those who drank more milk, nor was it associated with cough or congestion.

Myth 5: You lose most of your body heat through your head

A military study many years ago tested the loss of temperature in soldiers when exposed to very cold temperatures. They found rapid heat loss in the head – and so the idea that we lose heat through our heads was born. But what they didn’t tell you was that the soldiers were fully clothed except for their heads. This obviously skews the statistics considerably. The fact is, completely naked, you lose approximately 10% of your body heat through the head – the other 90% is lost via the other parts of your body.

Myth 6: Teething causes a fever

Scientific studies have been done in the area of teething which show no correlation at all between fever and teething. If your baby is suffering from a new tooth and they also have a fever, it is advisable to check for other causes of the fever. The same is true of diarrhea which is also often blamed on teething in infants. It is always better to be safe than sorry when dealing with the health of children.

Myth 7: Cancer treatment is painful and pointless – furthermore, it is incurable

While this may have been almost true thirty years ago, medical advances have meant that modern cancer treatments are far more effective and cause less suffering for the patient. A few decades ago, 90% of children with leukaemia died; today 80% survive. Many people think cancer is incurable as there isn’t a “one drug fixes all” cure, but there are many people who are completely cured of cancer. Various drugs exist to treat different types of cancer, and many of them are extremely effective and well worth trying if you do get the disease.

Myth 8: Back pain should be treated with bed rest

The opposite is actually true in this case. Bed rest can prevent the lower back from fully recovering – or at the very least, delay the recovery significantly. Patients who continue to engage in ordinary activities recover faster and usually have fewer problems with recurring pain and other back troubles. Interestingly, many studies have shown that this is not just true of back problems, but also many other medical problems. Thirty-nine independent studies found bed rest to be more harmful than good in a broad range of illnesses.

Myth 9: Eating turkey makes you sleepy because it contains tryptophan

This is one of the most common myths on this list – and it pops up every year around Thanksgiving. But actually, chicken and ground beef contain almost identical quantities of tryptophan as turkey does. Other foods such as cheese and pork contain significantly more of the chemical than turkey. So why do people think turkey makes them sleepy? It is most likely due to turkey appearing at very large meals often eaten during the day rather than the evening. The heavy meal slows blood flow which can cause drowsiness, and the timing can have a huge psychological impact: in other words, you are imagining it.

Myth 10: Eating at night makes you fat

Secret snackers rejoice! This is a complete myth. It doesn’t matter what time of day you eat, as long as you eat only the total calories that you burn each day, you will not gain weight. If you eat fewer calories than you burn, you will lose weight, and if you eat more calories, you will gain. It is as simple as that. Having said that, the routine of three meals a day at the same time each day can have other benefits in life (routine is good and it helps humans work more effectively), but snacks at night are no worse than snacks in the morning or afternoon.

Myth 11: It is harder to lose weight than to gain weight

Actually – once you get your head around a new eating pattern, math and science are working in your favour. It is mathematically easier to lose than to gain. For example, if you eat 3,500 calories more than you burn, you will gain 0.3 pounds (0.14 kg), but if you burn 3,500 calories more than you eat, you will lose 1 pound (0.45 kg). Also, if you want to lose weight, you can expose yourself to significant changes in temperature which speeds up your metabolism. Finally, the above information is based on a pure fat diet – variations to the math occur when you introduce other types of food.

Myth 12: Crunches get rid of belly flab

It seems common sense - to get rid of belly fat, work on your belly. Specifically, exercises like crunches will turn belly fat into muscle. Job done.

In fact, in a recent study by Duke University Medical Center in the US, aerobic exercise like jogging beat resistance training hands down when it came to battling belly bulge.

Myth 13: Shaving causes stubble to grow back faster and thicker

Every schoolboy knows that if you quickly shave off the first sight of bum fluff you find on your chin, you'll soon be sporting thick manly stubble. But then schoolboys are wrong about a lot of things.

And so are grown men, it seems. This popular myth was disproved as far back as 1928, when a study showed that shaving had no effect on hair growth. The myth might have come about because new stubble has not had chance to be lightened by the sun or chemicals in the environment, and darker hair can look thicker.

Myth 14: Mobile phones stop medical equipment working

The reason most people think there are signs in hospitals asking you to turn off your mobile phone is that they interfere with crucial, lifesaving hospital equipment. And indeed they can, very rarely, and if they're very close to the equipment in question.

In normal circumstances, mobile phones have no effect on hospital equipment. In 2007 a large study showed that mobile phones used in a 'normal way' caused no malfunction or interruption of any kind during 300 tests in 75 treatment rooms. The reason many hospitals want you to switch mobile phones off is to stop your conversations annoying other patients.

Myth 15: Hair and fingernails continue to grow after death

This common myth certainly seems to be true. After death, hair and fingernails can appear to be longer.

But it's an optical illusion. Dehydration of the body after death causes the skin to retract, giving hair and fingernails the appearance of growth. But growing requires complex bodily systems to be working, and after death they simply aren't.

Myth 16: Coffee will sober you up

It used to be quite normal for sozzled revellers to be offered a cup of black coffee to sober them up. It's less common now, for the simple reason that it doesn't work.

A male liver can only deal with about one normal sized alcoholic drink (a pint of normal strength beer, for example) an hour. No amount of coffee, orange juice or cola will make any difference to that. You'll stay drunk till your liver has metabolised much of the alcohol in your blood.

Alcohol does make you sleepy, and the caffeine in coffee (or cola) will perk you up a bit, so that's where this myth may have started.

Myth 17: Cracking your knuckles causes arthritis

It's one of the stranger manly quirks - that thing many of us do where we pull our fingers away from their sockets until the knuckles make a cracking sound. It was all the rage, right up until someone told us it could cause arthritis.

Well, we can go back to the knuckle-cracking, lads, because the arthritis thing is a myth. When your knuckles 'crack' it's simply the sound of nitrogen bubbles in the lubricating fluid between your joints bursting. This can cause some damage if you do it too much, but it has nothing to do with arthritis, which occurs when the body's immune system attacks its own joints.

Myth 18: Vaccines can cause the flu (and autism)

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While the body can react to any shot with a low-grade fever, rumours that a flu shot can cause the flu are "an outright lie," said Dr. Rachel Vreeman, co-author of “Don't Swallow Your Gum! Myths, Half-Truths, and Outright Lies about Your Body and Health” (St. Martin's Griffin, 2009). The flu shot does contain dead flu viruses but they are, well, dead. "A dead virus cannot be resurrected to cause the flu," Vreeman said. As for vaccines causing autism, this myth was started in 1998 by an article in the journal The Lancet. In the study, the parents of eight (count 'em, eight) autistic children said they believed their children acquired autism after they received a measles, mumps and rubella vaccination. Correlation was quickly confused with causation, and since then, rumours have run rampant despite many studies — such as a 2002 study in the New England Journal of Medicine of 530,000 (count 'em, 530,000) children — that have found nothing to suggest that vaccinations increase the risk of becoming autistic. Unfortunately, the endurance of this myth, said Vreeman, who also conducts paediatric research, continues to eat up time and funding dollars that could be used to make advances in autism, rather than proving, over and over again, that vaccinations do not cause the condition.

Myth 19: Supplements always make you healthier

Credit: Dreamstime

An increasing number of studies are finding that vitamin supplementation may not only be ineffectual but may even be dangerous. For example, people downing vitamins C and E may be predisposing themselves to cancer, according to a study published earlier this year in the journal Stem Cells, as high doses of these antioxidants can cause genetic abnormalities. Similarly, a study published this year in the journal Cancer Research linked fish oil supplements with cancer in mice. "The FDA does not require supplements to be regulated in the same way that drugs are, which can be a real problem," Vreeman said. As a result, the safety of many supplements has not been rigorously studied. Furthermore, the bottles can sport unsubstantiated claims and even make errors in dosage recommendations, she said. There is no need to worry about overdosing, however, if the good-for-you compound is coming from real food, rather than a pill. "A vitamin pill is not the answer," Vreeman said. "Eating more healthily in general is the answer."

Myth 20: Cold weather makes you sick

"This myth is common around the world, but it is just not true," Vreeman told My Health News Daily. Studies have shown we may feel more cold symptoms — real or imaginary — when we are chilled (after all, a cold is called a cold for a reason), but the temperature does not make us more susceptible to viruses. This has been known since at least 1968, when a study in the New England Journal of Medicine showed what happened when researchers exposed chilly people to the rhinovirus (one cause of the common cold). Whether shivering in a frigid room or stuttering in an icy bath, people were no more likely to get sick after sniffing cold germs than they were at more comfortable temperatures. And if you are already sick, there is no reason you can't go out into cold weather. While rest is good for an ill body, chilly temperatures aren't going to make a difference on recovery time, Vreeman said. In fact, while the research is in its early stages, "it is possible that being exposed to cold may even help your body in some way," she said. Some scientists speculate that colds are more common in cooler months because people stay indoors more, interacting more closely with one another and giving germs more opportunities to spread.

Myth 21: We use only 10 percent of our brains

Credit: Dreamstime

Motivational speakers and other self-help gurus have been promoting this one since as early as 1907, as a way to encourage people to tap into some latent capacity, explains Vreeman and co-author Aaron Carroll, both of Indiana University School of Medicine. But none of these people were basing the proclamation on sound science. Today, we can take a look at any brain scan, measuring activity at any given time, and have a big laugh at this myth. "You just don't see big dormant areas," Vreeman said. So why does the idea still linger in popular culture? "I think we like it," Vreeman said. "We want to think we haven't reached our full potential."

Myth 22: Sugar turns kids into little monsters

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It can be hard to find a parent that does not believe this, Vreeman said. "But it is in their heads." In one particularly clever study — among a slew of studies finding sugar's nil effect on unruliness — kids were given Kool-Aid sweetened with aspartame, a compound that contains no sugar. Researchers told half of the parents the Kool-Aid contained sugar, and told the other half the truth. The parents who thought their kids were riding a sugar-high reported their children were uncontrollable and overactive. But a sensor on the kids' wrists, that measured activity level, said the opposite: The kids were actually acting subdued. The study was published in the Journal of Abnormal Child Psychology in 1994. Sugar is often given at times when the rules are loosened and there are lots of other kids around — like birthday parties and holidays, Carroll said. These factors may be behind the myth's persistence in popular culture, he said.

Myth 23: You need to stay awake if you've had a concussion

This young football player wasn't hurt badly, but researchers say concussions among kids

who play organized team sports are on the rise. Credit: Susan Leggett | Dreamstime

Concussions are relatively common, and while they always merit medical attention, they are rarely severe or life- threatening. Warnings to stay awake after a concussion most likely grew out of a misunderstanding about a particular type of head injury — one that involves brain bleeding — where a "lucid period" is followed by a coma or worse. But this is very uncommon and doesn't pertain to people with normal concussions, Vreeman said. "If you've been evaluated by a doctor, and he has said that you have a mild regular concussion, you don't need to worry that someone has to wake you up every hour," she said.

Myth 24: Chewing gum stays in your stomach for 7 years

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While it is true that many of the ingredients in gum, such as elastomers, resins and waxes, are indigestible, that does not mean they hang out in our guts for a subset of eternity. Plenty of what we eat — even things we are recommended to eat, such as fiber — is indigestible. But the digestive system is a robust piece of organic machinery, and anything it can't absorb, it moves along. Despite the stickiness and strange consistency of gum, "it passes right through your digestive tract and into the toilet," Vreeman explained.

Myth 25: Reading in the dark or sitting too close to the TV ruins your eyesight

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Dim light, or alternatively, staring into the multi-coloured tube at close range, can undoubtedly make your eyes work so hard they hurt. But there is no evidence that these practices cause long-term damage, Vreeman said. The TV myth may have started in the 1960s, and at that time it may have been true. Some early colour TV sets emitted high amounts of radiation that could have caused eye damage, but this problem has long been remedied, and today's TV and computer monitors are relatively safe, she said. If you or your child tend to sit so close to the computer or TV it hurts the eyes, it may be time to check for near-sightedness. But sitting too close does not create a need for glasses — even if getting glasses can remedy the habit.

Myth 26: You should drink at least 8 glasses of water a day

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"In general, we are not all walking around in a dehydrated state," Vreeman said, adding that our bodies are very good at regulating our fluid levels. The eight-glasses-a-day myth likely started in 1945 when the Food and Nutrition Board of the National Research Council said adults should take in about 2.5 liters of water a day (equivalent to about eight glasses, or two-thirds of a gallon). While most media outlets reported just that, the council actually went on to explain that most of the 2.5 liters comes from food. The recommendation should be amended to: Drink, or eat, about eight glasses of fluid a day.

Myth 27: You should wait an hour after eating before you go swimming

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This myth has ruined many summer afternoons, forcing young and old to swelter in the heat while cool waters beckoned — all because they were careless enough to down a PB&J [peanut butter and jelly sandwich]. Let the ban be lifted: There is no special reason not to swim after eating, Vreeman said. True, any type of vigorous exercise can be uncomfortable (although not dangerous) after an overwhelming feast. But for most of us — whose waterfront dining experience includes sand-dusted chips and soggy sandwiches — that is hardly a concern. And cramps can happen anytime, whether you've eaten or not. If you are swimming in waters so rough that a charley horse will mean the death of you, you should probably swim elsewhere. Just don't forget the picnic!

Source: 

1. 10 Medical Myths That Just Won't Go Away
2. Medical Myths That Won’t Go Away
3. Top 10 Common Medical Myths
4. The Top 10 Untrue Medical Myths
5. Common Misconceptions Get Busted!