Let's examine a few things that are commonly believed about our bodies but aren't actually true.
1. We only use 10% of our brain.
We hear this in just about every movie that tries to make any magical power true to reality. If we only use 10% of our brains then we MUST be able to harness the other 90% to master our hidden ability to control matter around us to finally live out our dream of becoming a local vigilante. Maybe not, but despite the growing field of Neuroscience it is commonly believed that we only use 10% of our brain. This is actually
false.
Let's go back to basic middle school biology. Even then we learned that the brain is an incredibly complex organ. Scientists know some
very complicated things about our brains, yet we've barely scratched the surface on how everything inside that squishy thing in our noggin works. The brain literally controls every single thing that goes on inside of our bodies. Even as I'm sitting here typing out this blog entry my brain is in control of every single aspect of my actions. Without my brain I would be unable to recall the proper vocabulary and sentence skills to write, I would be unable to see the website that I'm using to communicate with and I would be unable to instinctively know which letter belongs where on the keyboard in order to use it to type.
It is true that we know very little about this spongy organ but we are constantly expanding our knowledge and understanding of how the brain works. One way that we learn how the brain works is to study people with brain damage to see what functions they are missing. One famous subject is a man called
HM who had parts of his brain removed to control severe epilepsy and suffered from a severe memory disorder as a result.
2. If you swallow gum it will stay in your body for 7 years.
I remember the rumor that gum stays in your body for 7 years being passed around the playground in elementary school. This was, of course, along side the kids daring you to swallow whatever they can find that will fit down the hatch. I can also see how, despite its status as a myth, it can serve as an easy tool to discourage kids from swallowing gum. No one wants to find out what happens when a wad of gum stays lodged in your intestines for that long. This is actually
false.
While it is true that gum is mostly indigestible it doesn't mean that it will stay in your body for 7 years. Gum is basically a synthetic rubber base with sweeteners, flavors and softeners such as vegetable oil. Since a standard piece of gum is small enough it will pass through the digestive tract in roughly the same shape as it entered. That said, it still isn't a good idea to swallow gum. There have been
reports of people having intestinal blockages due to gum combining with other wads of gum or even other bits of undigested food.
3. You will catch a cold if you don't bundle up in many layers of clothing on a cold day.
All of us have Moms that want us to stay warm and healthy during the winter months when it is oh-so-easy to pick up a cold or the flu which makes it easy for this rumor to stay alive. Moms around the world have been urging their children to bundle up before they go outside on a cold day to prevent catching colds ever since there have been Moms to bundle up their children. While the Mom's intentions are good and bundling up before going outside is the correct thing to do it actually has nothing to do with catching a cold. So, this is actually
false.
It is definitely more comfortable to bundle up on a cold day but a wool jacket isn't going to stop the cold virus from getting into your system. This myth is more than likely perpetuated because colds are more common when it's cold outside; maybe because people tend to stay indoors around each other more often when it's cold. I've even
read somewhere that it's easy to associate being cold with having a cold because our bodies react similarly (shivering, increased heart rate and cold extremities) in both circumstances.
4. Reading in dim light is bad for your eyes.
I've always been warned never to read by lamplight or flashlight because it is bad for your eyes if you read in dim light. This is actually
false.
Reading in dim light will cause eyestrain but studies have not shown any permanent damage occurring as a result. I would still recommend reading in a well-lit area to stay comfortable because eyestrain causes headaches and makes your eyes dry and itchy and all of that can take one's attention away from enjoying a great novel.
5. Your body needs 8 glasses of water every day.
You can ask almost anyone at the gym how much water one is supposed to drink every day and they would probably tell you 8 full 8 ounce glasses is what they've always heard. Whether or not they actually drink that much is up for debate, I know I don't even though that's what I've always heard. Turns out, this one's also
false.
It is recommended that you receive about that much in
fluids per day but your body gets that from the regular foods that one eats as well as any beverage that one drinks. Trying to drink 8 glasses of water plus the morning coffee and the 12 ounce soda with every meal plus the fluid content in all of the food can be tiring to say the least, not to mention the trips to the bathroom. You would have to chug an 8 ounce glass of water about every hour and a half all day to keep up. In the absence of any related health problems, trusting in your own thirst to let you know when you need more water is sufficient to keep one properly hydrated.
Sources:
http://www.snopes.com/science/stats/10percent.asp
http://www.bmj.com/content/335/7633/1288.full
http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-chewing-gum-takes-seven-years-to-digest
http://chemistry.about.com/od/chemistryfaqs/f/chewinggum.htm
http://theconversation.edu.au/mondays-medical-myth-you-can-catch-a-cold-by-getting-cold-2488 
