The human brain doesn't stop developing until about 25 years old.
102
The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21
The levels of two stress hormones, cortisol and epinephrine which suppress the body's immune system, will actually drop after a dose of laughter.
112
The average person's skin weighs twice as much as their brain.
131
In 30 minutes, the average body gives off enough heat (combined) to bring a half gallon of water to boil.
199
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
In ancient Egypt, priests plucked EVERY hair from their bodies, including their eyebrows and eyelashes.
130
The average sperm cell swims at 8 inches per hour.
76