Yawns are more contagious among people with closer relationships.
163
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The human brain uses approximately as much energy as a 10 watt light bulb.
120
One human hair can support 3 ounces.
191
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Your body is creating and killing about 2.4 million red blood cells per second.
17
If your DNA was stretched out it would reach to the moon 6,000 times.
256