It takes 17 muscles to smile, 43 to frown.
65
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Brain freeze is caused by the brain sensing the drop of temperature on your palate and increasing blood pressure in an attempt to save you from freezing.
14
Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
15
10 seconds is the amount of time until unconsciousness after the loss of blood supply to the brain.
108
Cigarette smoke contains 4,800 chemicals, 69 of which cause cancer.
145
The aorta, the largest artery in the body, is almost the diameter of a garden hose.
37
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99