6. In the original casting, Michael Keaton was set to play the character. However, ABC executives begged the writers and producers to keep Jack alive. They believed the character was too likeable to die off so quickly. The writers agreed. Michael Keaton was not interested in signing up for a long-running show. Instead, the role of Jack was given to Matthew Fox. The rest is TV history.
11. Our gut bacteria are messing with us in ways we could never have imagined. New research has revealed that neurodegenerative diseases like Parkinson's might actually start out in the gut, rather than the brain, and there's mounting evidence that the human microbiome could be to blame for chronic fatigue syndrome. With gut bacteria showing signs of controlling our appetite, changing our brain structure, and triggering brain lesions that could lead to strokes, our tiny passengers are a force to be reckoned with.