Men working rotating shifts are four times as likely to develop prostate cancer, compared to men who work just day shifts or night shifts, say scientists from the University of Occupational and Environmental Health, Japan, who carried out research on 14,052 workers.

You can read about this study in the American Journal of Epidemiology.

A baseline survey was carried out between 1988-1990. Participants had to indicate the most regular schedule they had undertaken previously:
— day work
— rotating shift work
— fixed night work

The scientists made adjustments for participants’ age, history of prostate cancer in the family, geographical area surveyed, BMI, smoking, alcohol consumption, type of job, physical activity in the workplace, where they worked, stress, educational level, and marital status.

31 cases of prostate cancer were recorded during 111,974 person-years.

The researchers found that men who worked fixed night shifts had slightly elevated prostate cancer risk, compared to men who worked fixed day shifts. They believe lower levels of melatonin, a hormone which regulates sleep patterns and has been shown to protect people from cancer, may be an important factor.

Previous studies have indicated a higher risk of breast and bowel cancer for shift workers.

“Prospective Cohort Study of the Risk of Prostate Cancer among Rotating-Shift Workers: Findings from the Japan Collaborative Cohort Study”
Tatsuhiko Kubo, Kotaro Ozasa, Kazuya Mikami, Kenji Wakai, Yoshihisa Fujino, Yoshiyuki Watanabe, Tsuneharu Miki, Masahiro Nakao, Kyohei Hayashi, Koji Suzuki, Mitsuru Mori, Masakazu Washio, Fumio Sakauchi, Yoshinori Ito, Takesumi Yoshimura and Akiko Tamakoshi
American Journal of Epidemiology 2006 164(6):549-555
Click Here To View Abstract

Written by: Christian Nordqvist
Editor: Medical News Today