Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Yawns are more contagious among people with closer relationships.
163
Enamel is hardest substance in the human body.
61
When you take a step, you are using up to 200 muscles.
886
Poor eyesight (myopia) is associated with higher IQ.
232
Your body is creating and killing about 2.4 million red blood cells per second.
17
There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.
62