Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Chewing gum boosts your brain power.
285
One human hair can support 3 ounces.
191
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Your body is creating and killing about 2.4 million red blood cells per second.
17
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55