Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
When you take a step, you are using up to 200 muscles.
886
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Every year your body replaces 98% of your atoms.
119