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
Every year your body replaces 98% of your atoms.
119
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Your thumb is about the same size as your nose.
124
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Poor eyesight (myopia) is associated with higher IQ.
232
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13