After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Your thumb is about the same size as your nose.
124
When you take a step, you are using up to 200 muscles.
886
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
Your body is creating and killing about 2.4 million red blood cells per second.
17