Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
If your DNA was stretched out it would reach to the moon 6,000 times.
256
The human body contains over a billion miles of DNA.
147
The human brain uses approximately as much energy as a 10 watt light bulb.
120
The average sperm cell swims at 8 inches per hour.
76
Your heart will pump about 212 million liters in its lifetime.
26
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127