Yawns are more contagious among people with closer relationships.
163
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Your thumb is about the same size as your nose.
124
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
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 doesn't stop developing until about 25 years old.
102
Enamel is hardest substance in the human body.
61