Yawns are more contagious among people with closer relationships.
163
The human brain uses approximately as much energy as a 10 watt light bulb.
120
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Enamel is hardest substance in the human body.
61
The largest cell in the human body is the female egg and the smallest is the male sperm.
682