Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Every year your body replaces 98% of your atoms.
119
Yawns are more contagious among people with closer relationships.
163
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149