It often happens when you hear a strange sound in the middle of night; your heart races, your eyes dilate, your entire body tenses. Whether that sound turns out to be an intruder or just your dog moving in another room, what you are experiencing is fear. We know fear affects your mind , but it also has an impact on your health.
Once the body experiences fear response, it is slow to relax. It is preparing itself for the next sound or next time it needs to get ready for flight or flee. This only gets worse when fear sensation is very strong or continues for a long time.
The body’s fear response includes an upsurge of adrenaline and cortisone. Long term exposure of these chemicals weakens immune system making it at increase risk of viruses and other pathogens.