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
The average person's skin weighs twice as much as their brain.
131
One human hair can support 3 ounces.
191
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
Every year your body replaces 98% of your atoms.
119