Yawns are more contagious among people with closer relationships.
163
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Every year your body replaces 98% of your atoms.
119
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The human brain doesn't stop developing until about 25 years old.
102
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.
62
The human brain uses approximately as much energy as a 10 watt light bulb.
120