Yawns are more contagious among people with closer relationships.
163
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
Enamel is hardest substance in the human body.
61
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The human brain doesn't stop developing until about 25 years old.
102