Enamel is hardest substance in the human body.
61
Chewing gum boosts your brain power.
285
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
The average person's skin weighs twice as much as their brain.
131
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
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The human brain uses approximately as much energy as a 10 watt light bulb.
120