Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
The average person's skin weighs twice as much as their brain.
131
All the chemicals in a human body combined are worth about 6.25 euro (if sold separately).
266
The human brain doesn't stop developing until about 25 years old.
102
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99