Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Enamel is hardest substance in the human body.
61
Your thumb is about the same size as your nose.
124
It takes about 20 seconds for a red blood cell to circle the whole body.
102
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The human brain doesn't stop developing until about 25 years old.
102
One human hair can support 3 ounces.
191