Your thumb is about the same size as your nose.
124
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Enamel is hardest substance in the human body.
61
Your body is creating and killing about 2.4 million red blood cells per second.
17
Yawns are more contagious among people with closer relationships.
163
Chewing gum boosts your brain power.
285
The human body contains over a billion miles of DNA.
147
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99