For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
The average sperm cell swims at 8 inches per hour.
76
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
The human brain doesn't stop developing until about 25 years old.
102
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18