Enamel is hardest substance in the human body.
61
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
The human brain has the capacity to store everything that you experience.
4k
Your body is creating and killing about 2.4 million red blood cells per second.
17
The human body contains over a billion miles of DNA.
147
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
Every year your body replaces 98% of your atoms.
119