Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Yawns are more contagious among people with closer relationships.
163
Our Right Lungs takes more air than our left lung.
194
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
It takes about 20 seconds for a red blood cell to circle the whole body.
102