The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
The human brain doesn't stop developing until about 25 years old.
102
Yawns are more contagious among people with closer relationships.
163
Poor eyesight (myopia) is associated with higher IQ.
232
Every year your body replaces 98% of your atoms.
119
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
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