For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Enamel is hardest substance in the human body.
61
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
The average sperm cell swims at 8 inches per hour.
76
The human brain has the capacity to store everything that you experience.
4k
The average person's skin weighs twice as much as their brain.
131