For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
One human hair can support 3 ounces.
191
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
The human brain uses approximately as much energy as a 10 watt light bulb.
120
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Your heart will pump about 212 million liters in its lifetime.
26