Men with jobs that require them to be physically active may be getting benefits beyond their salary and health insurance — they may be at a decreased risk of developing prostate cancer, according to a study at UCLA’s Jonsson Cancer Center.
Researchers studied more than 2,100 men who worked at the Rocketdyne rocket-engine testing facility in Los Angeles’ San Fernando Valley. The research team identified 362 men who developed prostate cancer and compared them with 1,805 men of similar age and socio-economic status who did not get prostate cancer.
The results show that those who developed prostate cancer were less likely to have held jobs requiring high amounts of physical exertion.
Physical activity was separated into three job groups:
- Low activity — managers, supervisors, analysts, administrators and senior engineers
- Moderate activity — senior mechanics and technicians, inspectors, and engineers
- High activity — Masons and bricklayers, metal fitters, welders, packers, painters, tool and die makers, truck drivers, lift operators, and janitors
The study found that the men who developed prostate cancer were less likely to have held the more physically active jobs.
The findings are supported by other studies suggesting that continuous physical activity — but not intermittent activity — is required to lower the risk of prostate cancer.
The biologic mechanisms by which physical activity lowers prostate cancer risk have not been identified, although some experts have speculated that activity can alter hormone levels in some men.
“The message from this study for today is that if you’re more active, you may be able to prevent this cancer from happening,” said senior author Beate Ritz, a Jonsson Cancer Center researcher and associate professor of epidemiology at the UCLA School of Public Health. “If you have a desk job, do something physically active to counterbalance it.”
Reference
Krishnadasan, A., Kennedy, N., Zhao, Y., Morgenstern, H., & Ritz, B. (2008). Nested case–control study of occupational physical activity and prostate cancer among workers using a job exposure matrix. Cancer Causes & Control, 19, 107-114.
