Stress: What Causes It

Research has linked chronic stress to digestive disorders, urinary problems, headaches, sleep difficulties, depression, and anxiety.

“Some studies have found the physical, emotional, and social effects of a disease like cancer to be stressful for patients, caregivers, and long-term cancer survivors,” says NIH’s Dr. Paige Green McDonald, an expert on stress and cancer biology. “However, there’s no definitive evidence that stress causes cancer or is associated with how long one survives after a cancer diagnosis.”

The top causes of stress in the U.S. are money and work-related pressures, according to a 2013 survey from the American Psychological Association. Stress can also arise from major life changes, such as the death of a loved one, divorce, illness, or losing a job. Traumatic stress is brought on by an extreme event such as a major accident, exposure to violence, or a natural disaster such as a hurricane or flood.

Caring for a person with severe illness—such as dementia or cancer—can also be a significant source of stress. More than a decade ago, studies by Kiecolt-Glaser and others showed that the stressful demands placed on caregivers can lead to poorer health, lower responses to vaccines, increased inflammation, and a more than 60% higher death rate compared to non-caregivers.

It’s not clear why some people can sidestep or recover more quickly from stress than others. These resilient people seem to “bounce back” more easily after stressful situations. Recent studies of animals suggest that resiliency may depend at least in part on our genes. But learning healthy ways to cope with stress can also boost your resilience.

“There are many different ways to cope with stress. We know from a lot of different studies that having close personal relationships—people with whom you can talk, with whom you can share your feelings—can be helpful,” says Kiecolt-Glaser. “So spending time with family and friends in order to maintain those relationships is perhaps one of the most crucial things you can do as a stress reducer.”

Unfortunately, Kiecolt-Glaser adds, “when we’re stressed, we tend to do the worst things that are not at all helpful to our health.”

For instance, stressed out people may tend to isolate themselves and not seek social support. “Exercise is a great stress reducer. But when people are stressed, exercise becomes less common and less appealing,” Kiecolt-Glaser says. “Instead of maintaining a healthy diet—also important to reducing stress—some people who are stressed tend to eat more donuts than vegetables.”