It takes about 20 seconds for a red blood cell to circle the whole body.
102
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
When you take a step, you are using up to 200 muscles.
886
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
If your DNA was stretched out it would reach to the moon 6,000 times.
256
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127