The human brain doesn't stop developing until about 25 years old.
102
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
One human hair can support 3 ounces.
191
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
The human body contains over a billion miles of DNA.
147