Science has found for years that stress has serious health impacts. But recent studies around the U.S. have shown that a bad mood or a negative outlook on life can put you at risk for severe diseases and conditions later in life.
In a TIME article, Emiliana Simon-Thomas, Ph.D., a science director at UC Berkeley said, “Many negative emotions such as anger, fear and frustration become problematic when those emotions turn into a more permanent disposition or a habitual outlook on the world.”
One example of this is hostility. A 2014 study in Stroke showed that unfriendly people had a higher risk of stroke than other kinder, friendlier participants.
Negative thinking in the form of cynicism can also cause some serious diseases down the line. One study in Neurology showed that cynical or distrustful people have a greater risk of dementia as compared to those who were more trusting. Another 2009 study found that cynical participants were more likely to have heart disease. In addition, pessimistic women had a higher chance of dying over the study period than the optimistic women participants.
Lastly, there is depression, which is a serious and dangerous diagnosis. Most people know the usual effects of depression: loss of appetite, mood swings, no motivation. However, it has also been connected with an increased risk for type 2 diabetes and heart attacks.
One explanation for this could be that feeling bad leads many people to skip workouts, drink alcohol or smoke heavily—which could all affect one’s health. Another idea is that stress and sadness increase cortisol levels. An increase in cortisol levels weakens the immune system, making it less able to control inflammation over time. According to Simon-Thomas, our thoughts and emotions have considerable effects on many of the everyday bodily processes.
One easy fix could be simply changing your perspective, or seeking out professional health. Cynical or hostile people can try to see the world as a friendlier, more trusting place, if only for the sake of health. As if there weren’t enough reasons to seek out help for depression, it could protect you against other severe diseases, as well. As Simon-Thomas said, “We can be deliberate about shifting our habits of feeling and thinking in the world.”