Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
An Indian man known as "Snake Manu" can put small snakes, including deadly cobras, into his mouth and pass them out through his nose.
59
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Every year your body replaces 98% of your atoms.
119