Here are ten tired old myths that a lot of people still think are true . . .
Myth #1: Cracking your knuckles causes arthritis. It might cause weakness in your hands, but there's no proof it causes full-on arthritis.
Myth #2: We only use 10% of our brain. A survey a while back found two-thirds of us believe that one. But even with simple tasks, you're still using most of your brain. It takes so much energy that up to a fifth of the calories you eat go toward keeping your brain working.
Myth #3: Dogs see in black-and-white. The newest science says they probably DO see colors, just not as many as we do. They're basically red-green colorblind.
Myth #4: If you swallow a piece of gum, it takes seven years to digest. The truth is that just like corn, your body CAN'T digest it. But it doesn't stay in there for seven years. It moves through your body just like everything else you eat. It just doesn't break down.
Myth #5: Shaving makes your hair grow back thicker. Some people think that because the tips of your hair feels coarser after they're been cut. But shaving doesn't make it grow back thicker.
Myth #6: You swallow eight spiders a year in your sleep. It's just an urban legend. As far as anyone can tell, there's no truth to it.
Myth #7: Our blood is blue before it's exposed to oxygen. No, it's always red. Your veins just look blue because of how light travels through our skin.
Myth #8: Coffee stunts your growth. The main thing that CAN stunt a kid's growth is poor nutrition. But coffee and caffeine don't do it.
Myth #9: Your dog's mouth is cleaner than our own. Also not true. Dogs and humans BOTH have around 600 different types of bacteria in their mouth. Plus, we brush our teeth every day . . . and you've seen what your dog eats.
Myth #10: Public swimming pools have a chemical that turns blue if you pee in them. That's just something parents tell their kids. There's no chemical that can do that just to urine.
Source: BuzzFeed