Yawns are more contagious among people with closer relationships.
163
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
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
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
The average person's skin weighs twice as much as their brain.
131
Enamel is hardest substance in the human body.
61