20 Amazing Facts about human beings

1.  People with higher number of moles tend to live longer than people with lesser number of moles.
2. When filming summer scenes in winter, actors suck on ice cubes just before the camera rolls - it cools their mouths so their breath doesn’t condense in the cold air. 
3. Thinking about your muscles can make you stronger.
4. Grapefruit scent will make middle aged women appear six years younger to men. The perception is not reciprocal and the grapefruit scent on men has no effect on women’s perception.
5. The world’s youngest parents were 8 and 9 and lived in China in 1910.
6. The colder the room you sleep in, the better the chances are that you’ll have a bad dream.
7. There are more people alive today than have ever died.
8. Women’s hair is about half the diameter of men’s hair.
9.  Women blink twice as many times as men do.
10. The average person who stops smoking requires one hour less sleep a night.
11. 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.
12. Intelligent people have more zinc and copper in their hair.
13. The human heart creates enough pressure while pumping to squirt blood 30 feet!
14. The brain operates on the same amount of power as 10-watt light bulb. The cartoon image of a light bulb over your head when a great thought occurs isn’t too far off the mark. Your brain generates as much energy as a small light bulb even when you’re sleeping.
15. The brain is much more active at night than during the day.
16. The brain itself cannot feel pain. While the brain might be the pain center when you cut your finger or burn yourself, the brain itself does not have pain receptors and cannot feel pain.
17. 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. Why is not entirely known, but nail growth is related to the length of the finger, with the longest fingers growing nails the fastest and shortest the slowest.
18. The lifespan of a human hair is 3 to 7 years on average.
19. 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.
20. 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 the pizza you had for dinner but can also eat through many types of metal.