A human being can survive entirely on a diet of potatoes and butter. These two contain all the necessary nutrients that the human body needs. A human being can survive for weeks without eating, but can only live for 11 days without sleeping.
The left lung of the human body is smaller than the right to create space for the heart. Laughing lowers stress levels and strengthens the immune system. On average a 6-year old laughs 300 times a day while adults laugh between 15 to 100 times each day.
Sneezing kills some of the brain cells. Holding one's nose and mouth while sneezing may blow out a person's eyeballs. The human body contains 300 bones at birth and by the time a person reaches adulthood they reduce to 206. One fourth of these bones are in the feet. The thigh bones are stronger than concrete.
Only two animals in the world can see behind them without turning their heads. These are the rabbit and parrot. A cockroach can live for several weeks after it's head is cut off and a cow produces 200 times more gas each day than a human being. A giraffe can clean its ears using its tongue and stays without water for longer periods than a camel.