Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Your body is creating and killing about 2.4 million red blood cells per second.
17
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Your heart will pump about 212 million liters in its lifetime.
26
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
It takes about 20 seconds for a red blood cell to circle the whole body.
102