Who managed to ask someone who had a falling dream and died what they were dreaming before they died?
In the case of a heart attack... body caused the dream of falling not the dream caused the heart attack. In other words the body triggered the dream. The falling sensation is often associated with a sudden drop in body temperature.
Now mankind has been dreaming for eons and looking at the population it doesn't appear to be that detrimental. Afterall many more can cite helpful information coming from fearful dreams. The reason some of our dreams are scary is so that we will remember them when we wake up. If you develop the habit of recalling your dreams and decoding them you need less fearful dreams to trigger recall.
Dreams that result from reading are your own imagination. When you consider the monsters created for movies not only has the storyline been imprinted on your mind. Vivid images that you may not have created using your own imagination have been planted there. You choose what you watch, you choose what you read and believe it or not you can control your dreams.
Try using a www search engine if you want to know more about dreams.
Alex