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Consider the following two questions:
1. During the past 12 months, would you say that you experienced a lot of stress, a moderate amount of stress, relatively little stress, or almost no stress at all?
2. During the past 12 months, how much effect has stress had on your health—a lot, some, hardly any, or none?
In 1998, over 20,000 Americans responded to these two questions, among others, as part of a national survey. A little over half of the respondents reported experiencing moderate amounts of stress or a lot of stress, and around one-third reported that stress had at least some effect on their health. The researchers then used death records to track their respondents' mortality between 1998 and 2006.
Surprisingly, stress levels alone didn't predict mortality risk—stress was only associated with mortality for respondents who also believed that stress affected their health. Participants who were stressed and who felt that stress affected their health were 43% more likely to die before 2006, compared to those who scored low on both of these measures.
Another study, which tracked thousands of British civil servants from 1985 to 2003, found similar results: Participants who felt that their health had been significantly affected by stress were twice as likely to have a heart attack—and to die from one—over the 18-year period, compared to participants who didn't believe that stress affected their health.
In both studies, researchers controlled for a range of health risk factors, including stress levels, suggesting that, independent of how much stress participants experienced and what their health status was to begin with, their perceptions of the harmfulness of stress adversely affected their health.
It's possible, though, that those who believed stress affected their health and those who didn't were different from one another in unmeasured ways. For example, those who believed that stress affected their health may have noticed a direct connection between stress and physical symptoms—that is, they could have been correct about stress affecting their health—whereas others may simply not have experienced that connection in their own lives. Different forms of stress can affect health in different ways, and individuals may differ in their vulnerability to stress-related health effects.
Still, these results are shocking. Is it possible that this belief alone could have such strong biological effects?
It may be that the belief that stress harms health makes stress even more stressful. An experience that is already stressful becomes even more stressful when we worry that it could also make us sick. Research has shown that the more an experience is perceived as threatening or dangerous, the greater the magnitude of the psychological and biological response. Over time, repeated heightened responses can increase biological wear-and-tear and, in turn, increase disease risk.
Another possibility is that people who believe stress affects their health may feel a lower sense of control over their health, which has been linked with poor health outcomes. However, the reverse could also be true: Individuals who believe that stress affects health may be more likely to blame themselves for health problems, thinking that they should be able to reduce their stress levels but have failed to do so. And self-blame may further jeopardize health: Research suggests, for example, that self-blame is associated with impaired immune functioning among workers and increased symptoms of anxiety and depression among women with breast cancer.
Besides potentially creating a self-fulfilling prophecy, the other problem with the belief that stress harms health is that it's not entirely true.
The body's stress response evolved to help us meet the demands of our environment and to increase our likelihood of survival in dangerous situations. There have probably been plenty of times in your life when the adrenaline rush of a stressful situation got you moving faster and thinking clearer—and maybe even saved your life. Stress-related arousal may help us perform better on exams and other challenging tasks, and research suggests that people who have experienced moderate stress in their lives are less likely to suffer harmful biological consequences, such as DNA damage, from subsequent stress. Even severe forms of stress can have upsides—they can make us stronger, more resilient, and more compassionate towards others who are going through stressful experiences.
This is not to say that we should seek out stressful experiences, but given that stress is a common and inevitable part of life, we may as well try to find a way to live peacefully with it, rather than seeing it as the enemy.
When we're constantly battling stress, we're destined to lose.
