Enamel is hardest substance in the human body.
61
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It takes about 20 seconds for a red blood cell to circle the whole body.
102
One human hair can support 3 ounces.
191
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Chewing gum boosts your brain power.
285
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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