For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
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 doesn't stop developing until about 25 years old.
102
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Your thumb is about the same size as your nose.
124
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
One human hair can support 3 ounces.
191