Your body is creating and killing about 2.4 million red blood cells per second.
17
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
Your thumb is about the same size as your nose.
124
An Indian man known as "Snake Manu" can put small snakes, including deadly cobras, into his mouth and pass them out through his nose.
59
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
One human hair can support 3 ounces.
191
If you are cold you are more likely to be hungry because you use energy to keep warm.
143