Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
It takes about 20 seconds for a red blood cell to circle the whole body.
102
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
One human hair can support 3 ounces.
191
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Every year your body replaces 98% of your atoms.
119