Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Enamel is hardest substance in the human body.
61
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Every year your body replaces 98% of your atoms.
119
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118