For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
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
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Enamel is hardest substance in the human body.
61
The human brain uses approximately as much energy as a 10 watt light bulb.
120
The average sperm cell swims at 8 inches per hour.
76