For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Chewing gum boosts your brain power.
285
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The average sperm cell swims at 8 inches per hour.
76
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18