Humans only use a fraction of their brain power, eating at night makes you fat and vitamins are good for you, right? You could be in for a surprise! We count down the top 10 medical myths everyone believes...
10. Shot through the heart
Pulp Fiction, The Rock, Robocop... Hollywood has perpetuated the lie that injecting adrenaline straight to the heart will revive a dying patient. If you stick a needle in your heart, you'll puncture the muscle and bleed to death. You're also likely to puncture your lungs in the process, causing you to suffocate whilst your heart fails. The proper approach is to inject medicine intravenously through a an IV line, where it will reach the patient's heart in less than a minute.
9. We only use 10% of our brain
This pseudo science originates from psychologist William James' 1908 book The Energies of Men, when he said that: "we are making use of only a small part of our mental and physical resources." In fact, neurologists have discovered that we really use 100% of our brain. Even during sleep, neurons in the brain fire as much as they do in waking hours.
Our metabolism slows down when we sleep, so late night calorie-consumption must be stored as fat, right? Well, not really. The most important element is the total amount of calories consumed, not when you consume them. Whether you eat a load of chocolate bars at 10am or 10pm makes no difference - if you eat more than the daily recommended amount of calories, it can be stored as fat.
7. Cold weather makes you sick
Tropical regions of the world are not immune to influenza. Cold weather has no direct effect on viruses, but it does drive us indoors, which puts us in close proximity to more people, which enables influenza to spread more quickly.
6. Vitamins are good for you
The vitamin industry is worth billions of pounds. Yet an increasing number of studies show that unless you're elderly or sick, vitamins are ineffective and possibly even dangerous. Too much vitamin E has been proven to increase your chance of developing cancer by 17%. Fat soluble supplements like vitamin A can cause blindness, cell degeneration and hair loss.
5. Sugary foods cause hyperactivity in children
Research has found no link between sugar and hyperactive behaviour in children. The usual times when children tend to eat more sugar are also when they're likely to be more excitable, such as birthday parties, Christmas and Halloween.
4. Drink eight glasses of water or more
Staying hydrated is important for our health but too much water can be lethal - drink six litres of water and you're likely to get water poisoning. When we drink too much water, the kidneys can't remove it from the body, lowering salt concentrations in the blood. This causes the brain to swell which impairs breathing and can can lead to organ failure.
3. Cracking your knuckles gives you arthritis
Studies have found no proof that knuckle cracking increases the risk of arthritis. One Californian doctor carried out a self-experiment for 60 years. He repeatedly cracked the knuckles on one hand, while leaving the other un-cracked. At the end, he reported: "not the slightest sign of arthritis in either hand".
2. A hair of the dog cures a hangover
Don't bother with that Bloody Mary! Most experts agree that downing more alcohol after a heavy-night simply delays the symptoms of a hangover, and might even make it worse.
1. Swallowed gum takes seven years to pass through your digestive system
Doctors have occasionally reported finding chewing gum in a patient's digestive tract, but these pieces have never been more than one week old. It's true that gum can withstand stomach acids but provided the gum is less than 2cm in diameter, our bodies have no problem passing it through our digestive system within 6-8 hours – as quickly as any other food.
Three products that may (or may not) help to improve your health:
NasalGuard Cold & Flu Block Topical Gel 3g, £9.99
Boots VITAMIN C & ZINC Orange Flavour 20 Effervescent Tablets, £3.99
Good Night Snoring Ring, £29.99