Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
An Indian man known as "Snake Manu" can put small snakes, including deadly cobras, into his mouth and pass them out through his nose.
59
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
The average person's skin weighs twice as much as their brain.
131
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99