Human teeth are almost as hard as rocks!
47
If you were to roll a lung from a human body and out flat it would be the size of a tennis court.
36
According to one report, it would take 800 marijuana joints to kill a person - but the cause of death would be carbon monoxide poisoning.
176
Deep Breathing gives you health benefits similar to aerobics.
39
The human brain doesn't stop developing until about 25 years old.
102
Smokers get ten times more wrinkles than non-smokers.
171
Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
13
Bearing a male child can alter a woman's brain by leaving male DNA that can persist for the rest of her life, making her less likely to suffer from Alzheimer's disease, promote tissue repair, and improve her immune system.
16