Your thumb is about the same size as your nose.
124
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Enamel is hardest substance in the human body.
61
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The average person's skin weighs twice as much as their brain.
131