Every year your body replaces 98% of your atoms.
119
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Enamel is hardest substance in the human body.
61
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Yawns are more contagious among people with closer relationships.
163
It takes about 20 seconds for a red blood cell to circle the whole body.
102
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127