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
The human body contains over a billion miles of DNA.
147
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
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
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13