Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
The average sperm cell swims at 8 inches per hour.
76
Enamel is hardest substance in the human body.
61
Every year your body replaces 98% of your atoms.
119
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111