Parkinson's and Alzheimer's are the most common types of neurodegenerative diseases. According to the Alzheimer's Association, one in three seniors dies with Alzheimer's or another type of dementia.

Narcolepsy is a nervous system condition that causes atypical sleep patterns. In addition to EDS and cataplexy, people with narcolepsy sometimes have “sleep attacks” (suddenly falling asleep).

And hunter-gatherers – people who live by hunting animals and gathering plants to eat – don't either – probably because they take a lot of physical exercise during the day. Alice ...

Click through this gallery to see which stars sadly died as a result of alcohol abuse.