Strong negative emotions can damage the immune system.
It wasn’t long ago that it was thought that emotions had no effect on the immune system. Perhaps you’ve seen the commercials that say that depression can cause physical pain. Well it’s true; your emotions have a profound effect on your well-being.
It turns out that something as simple as good feelings have healing effects on the body with everything from HIV to the flu. It’s been proven that those with a negative outlook will take longer to heal from illness, as well as physical injury. According to Martin Seligman, an expert in the field of positive psychology, there are four things that affect our health that we have control over: smoking, exercise, diet, and optimism.
According to Seligman, optimism is at least as important as the others. Though scientists don’t fully understand the biological mechanisms at work, they know that negative emotions can cause a spike in the hormone known as cortisol, which suppresses the immune system, making it harder to get better.