For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Yawns are more contagious among people with closer relationships.
163