Another Ten Interesting Facts About Humans

1. Laughing lowers levels of stress hormones and strengthens the immune system. Six-year-olds laugh an average of 300 times a day. Adults only laugh 15 to 100 times a day. Am glad I have not grown up.
   
2. Intelligent people have more zinc and copper in their hair.
3. The human heart creates enough pressure while pumping to squirt blood 30 feet.
4. The brain operates on the same amount of power as 10-watt light bulb. Your brain generates as much energy as a small light bulb even when you are sleeping.
5. The brain is much more active at night than during the day.
6. The brain itself cannot feel pain. The brain might be the pain center when you cut your finger or burn yourself, but the brain itself does not have pain receptors.
7. The fastest growing nail is on the middle finger and the nail on the middle finger of your dominant hand will grow the fastest of all. Nail growth is related to the length of the finger, with the longest fingers growing nails the fastest and shortest the slowest.
8. The lifespan of a human hair is 3 to 7 years on average.
9. Human hair is virtually indestructible. Aside from it’s flammability, human hair decays at such a slow rate that it is practically non-disintegrative. Hair cannot be destroyed by cold, change of climate, water, or other natural forces and it is resistant to many kinds of acids and corrosive chemicals.
10. The acid in your stomach is strong enough to dissolve razorblades. Hydrochloric acid, the type found in your stomach, is not only good at dissolving pizza, but can also eat through many types of metal.

Wordology, Lunule

The white, crescent shaped part at the top of a nail.

Medical Myth

Contrary to the myth, fingernails and hair do not continue to grow after death. What does happen is that the cuticles and skin shrink after death, making it appear as if the nails and hair were lengthening.