1. Your skin loses about fifty thousand dead cells every minute. That adds up to about three million cells every hour. No wonder dead skin is the main ingredient in household dust!
2. More than 11 miles (17.7 kilometers) of blood vessels crisscross your skin—and it’s a good thing, too. Your skin needs a never-ending flood of blood to live and grow.
3. Inside your skin 2 million sweat glands are constantly cranking out a fresh supply of sweat. Most days your sweat glands produce enough sweat to fill a 1-liter soda bottle. On really hot days you churn out ten times as much. That’s a lot of sweat!
4. More than 5 million short, thin strands grow on your arms and your legs and even on your back. Only three places don’t have hair—your lips, the palms of your hands, and the bottoms of your feet.
5. Your hair grows about 0.5 inches (1.2 centimeters) a month. At that rate it doesn’t take long to grow a new eyelash or an eyebrow hair. The hairs in your scalp can keep on growing for seven years or more.
Looking for more Gross and Goofy Body facts? Check out my book The Skin You’re In: The Secrets of Skin. It’s full of weird, wacky, strange, and surprising information about your body and the bodies of other animals.