It takes about 20 seconds for a red blood cell to circle the whole body.
102
Poor eyesight (myopia) is associated with higher IQ.
232
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
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
One human hair can support 3 ounces.
191
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18