Yawns are more contagious among people with closer relationships.
163
One human hair can support 3 ounces.
191
Enamel is hardest substance in the human body.
61
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Your heart will pump about 212 million liters in its lifetime.
26
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
The largest cell in the human body is the female egg and the smallest is the male sperm.
682