For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The average sperm cell swims at 8 inches per hour.
76
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
-137
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Yawns are more contagious among people with closer relationships.
163
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Your heart will pump about 212 million liters in its lifetime.
26