It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
The average sperm cell swims at 8 inches per hour.
76
Yawns are more contagious among people with closer relationships.
163
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
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
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118