Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Enamel is hardest substance in the human body.
61
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
If you are cold you are more likely to be hungry because you use energy to keep warm.
143