For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Your thumb is about the same size as your nose.
124
Enamel is hardest substance in the human body.
61
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Every year your body replaces 98% of your atoms.
119
There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.
62
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
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