Night shift work appears to increase the risk of cardiovascular disease (CVD) and cancer. The World Health Organization considers night shift work a “probably carcinogen” due to the disruption in the circadian rhythm in the worker.  The American Journal of Preventive Medicine recently published a study concluding that rotating night shifts for 5 or more years is associated with modest increase in the all-cause and CVD mortality. Those who work 15 or more years in rotating night shift work appear to have a modest increase in lung cancer mortality. The article indicates that the Nurses’ Health Study (NHS), a study of almost 75,000 registered U.S. nurses, the authors analyzed 22 years of follow-up and found that working rotating night shifts for more than five years was associated with an increase in all-cause and CVD mortality. Mortality from all causes appeared to be 11% higher for women with either 6-14 years or those with 15+ years of rotating night shift work. CVD mortality appeared to be 19% and 23% higher for those groups, respectively. There was no association between rotating shift work and any cancer mortality, except for lung cancer in those who worked shift work for 15 or more years (25% higher risk). Sleep and the circadian system play an important role in cardiovascular health and antitumor activity. There is substantial biological evidence that night shift work enhances the development of cancer and CVD, and contributes to higher mortality. ELSEVIER HEALTH SCIENCES Ann Arbor, MI, January 5, 2015 Source: