Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
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
The average sperm cell swims at 8 inches per hour.
76
Enamel is hardest substance in the human body.
61
Yawns are more contagious among people with closer relationships.
163
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92