Every hour one billion cells in the body must be replaced.
17
Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
15
It takes about 20 seconds for a red blood cell to circle the whole body.
102
You're born with 300 bones, but when you get to be an adult, you only have 206!
17
A woman's sense of smell is most sensitive during ovulation.
34
Your hair grows faster in the morning than at any other time of day.
91
Dieters who sleep more take off more fat that those who sleep less.
159
The human brain uses approximately as much energy as a 10 watt light bulb.
120