Ten Sleep Facts That May Surprise You

I think we all know that sleep is not only beneficial for good
health, but lack of sleep can lead to a number of serious disorders and
diseases.   Here are ten sleep facts that may surprise you:

1.    When we are awake our brain cells produce adenosine as a byproduct. The
build-up of adenosine in the brain is thought to be one factor that
leads to our perception of being tired. (