Night Shifts May Be Linked to Increased Ovarian Cancer Risk

http://www.sciencedaily.com/releases/2013/03/130315074722.htm

sciencedaily.com | Mar 14th 2013

— Working night shifts might increase the risk of developing ovarian cancer, indicates research published in Occupational and Environmental Medicine.

The risk may be lower for night types ("owls") than for morning types ("larks"), the findings suggest.

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Working night shifts was associated with a 24% increased risk of advanced cancer and a 49% increased risk of early stage disease compared with those who worked normal office hours.

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Only women aged 50 and above were significantly more likely to have ovarian cancer if they had worked nights.

The authors say their findings are consistent with, and of a similar magnitude, as those found for breast cancer, but point out that they did not find any cumulative risk for ovarian cancer the longer a woman had worked a night shift pattern.

One possible explanation could be linked to melatonin, a powerful hormone that is normally produced at night, but suppressed by ambient light, and which regulates reproductive hormones, particularly oestrogen.

Melatonin also scavenges harmful free radicals and boosts production of other antioxidants in the body.