Your thumb is about the same size as your nose.
124
Enamel is hardest substance in the human body.
61
Poor eyesight (myopia) is associated with higher IQ.
232
The average sperm cell swims at 8 inches per hour.
76
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Yawns are more contagious among people with closer relationships.
163