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
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
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
Every year your body replaces 98% of your atoms.
119
When you take a step, you are using up to 200 muscles.
886
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Yawns are more contagious among people with closer relationships.
163