Enamel is hardest substance in the human body.
61
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
Yawns are more contagious among people with closer relationships.
163
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
Chewing gum boosts your brain power.
285
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73