Keep the Sleep! While You Were Sleeping: Fun Facts That Happen at Night by Steve Murri
When you're asleep, the fingernails on your dominant hand (lefty or righty) grow more than on the other hand! And you replace all those dead skin cells you were shedding (yuk!) all day long.
While you snooze, your brain stays on, but it cools down--as much as 2 degrees lower than its standard operating temperature and requires 25% less blood flow.. Your heart slows down about 12 beats per minute and your blood pressure drops.
What does your body do with all that energy it's saving? It fixes things! Human growth hormone (HGH) is only released during rest. Muscles that have been strained are repaired. Worn-out red blood cells are recycled to make fresh new ones. And kids do most of their growing in the somnolent state. So even though staying up late may get you to the next level on your favorite game, it won't make you tall and strong and smart enough to do big things in the real world, so GET YOUR ZZZZZs!
And while the human body is recharging itself on this side of the date line, all kinds of things are going on on the other side of the earth with folks on the diurnal swing shift, in Steve and Matthew Murrie's latest compendium, While You Were Sleeping (Fun Facts) (Scholastic, 2012) This latest includes chapters about the nocturnal side of the human body, sports, pop culture, space, and the animal world. This sequel follows the Murries' companion book, Every Day On Earth: Fun Facts That Happen Every 24 Hours (Scholastic, 2011), another of those fun factoid collections that are the nonfiction analog to eating peanuts--fun for light browsing and yet filled with food for thought.