Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
When you take a step, you are using up to 200 muscles.
886
Your body is creating and killing about 2.4 million red blood cells per second.
17
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
The human brain doesn't stop developing until about 25 years old.
102
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
-137
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127