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
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266
Your heart will pump about 212 million liters in its lifetime.
26
The average sperm cell swims at 8 inches per hour.
76
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The average person's skin weighs twice as much as their brain.
131