For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
In 30 minutes, the average body gives off enough heat (combined) to bring a half gallon of water to boil.
198
The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
There's 100 trillion good bacteria living in your body.
17
If your DNA was stretched out it would reach to the moon 6,000 times.
256
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22