Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The average person's skin weighs twice as much as their brain.
131
Your body is creating and killing about 2.4 million red blood cells per second.
17
The human brain uses approximately as much energy as a 10 watt light bulb.
120
When you take a step, you are using up to 200 muscles.
886
Yawns are more contagious among people with closer relationships.
163
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13