I’m sure you have probably encountered the phrase “scared to death” at some point in your life. Most people think of it as just that, a common phrase. But this time of year, when all the ghouls and goblins come out to play, and haunted houses are more popular than theme parks (unless, of course they are IN a theme park), one does seem to wonder if they really can be scared to death.
Being scared is a natural response. When you are scared your adrenal glands pump adrenaline throughout your body, as a result of the fight or flight response. Usually this hormone does not course through your body in high enough concentrations to be dangerous, but scary stimuli can kick adrenaline production into overdrive. In normal amounts, adrenaline helps to increase heart rate, increasing blood flow to the muscles, dilating the pupils, and slowing digestion, all of which increases the chances of succeeding in a fight or running away from a rotting zombie. There is, however, a downside to all of this. Large amounts of adrenaline can be toxic and damaging to the heart, lungs, liver, and kidneys. The heart is the only muscle in the body that can cause absolutely sudden death. When adrenaline floods into your heart and contracts it, if the flow of adrenaline is not decreased, the heart will not be able to relax, causing your heart to fail.
If you are prone to heart conditions, you are more likely to be scared to death, but it can happen to anyone. Fear isn’t the only trigger either, extreme emotions of all kinds can trigger a greater release of adrenaline. But even in people who are prone to heart conditions, the chances of being scared to death are extremely low. So feel free to enjoy those haunted houses. Have fun scaring your friends.
How Stuff Works: http://science.howstuffworks.com/life/scared-to-death.htm
Live Science: http://www.livescience.com/52573-can-you-die-of-fright.html
Scientific American: https://www.scientificamerican.com/article/scared-to-death-heart-attack/