People who are stressed out by their jobs can let out a sigh of relief: It's unlikely all that job stress increases your risk of cancer, reports a new study from Europe.
Researchers analyzed information from 12 previously published studies involving more than 116,000 employed people in Finland, France, the Netherlands, Sweden, Denmark, or the United Kingdom. The study participants, who ranged in age from 17 to 70, had rated the mental demands of their job as well as the amount of control they had at work.
The researchers examined hospital records and death registers in determining cancer diagnoses.
Over the 12-year study period, 5,765 people developed colorectal, lung, breast or prostate cancer.
No link was found between high levels of job strain (defined as high demands at work with low control) and people's overall risk of cancer. There also was no association found between job strain and each of the four cancers.
The researchers took into account factors that could affect the association between mental stress and cancer risk, including age, sex, body mass index, socioeconomic status (based on job title or education level), and smoking and alcohol intake.
"Though reducing work stress would undoubtedly improve the psychological and physical well-being of the working individuals as well as the working population, it is unlikely to have an important impact on cancer burden at a population level," the researchers wrote in the Feb. 7 issue of the British Medical Journal (BMJ).
Mental stress can increase inflammation in the body, which in turn may play a role in cancer development, the researchers said. But previous searches for a link between stress and cancer were inconclusive. By contrast, previous studies have found a link between work stress and an increased risk of heart attacks and strokes.
The new study did not address whether mental stress from other causes, such as stressful life events or job insecurity, might be linked to cancer, and whether work stress is related to the risk of types of cancers not assessed in this study, the researchers said. The study also did not assess the duration of work stress, so it's possible long-term exposure to work stress might affect the risk of cancer.