Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
The human body contains over a billion miles of DNA.
147
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99