Every year your body replaces 98% of your atoms.
119
The human brain doesn't stop developing until about 25 years old.
102
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
One human hair can support 3 ounces.
191
The average sperm cell swims at 8 inches per hour.
76
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18