Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Yawns are more contagious among people with closer relationships.
163
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Our Right Lungs takes more air than our left lung.
194
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
If your DNA was stretched out it would reach to the moon 6,000 times.
256