In 2008, 38 Danish women who had developed breast cancer, sued their employers for compensation. The cancer had developed after the women began doing night shifts. Coincidence? The government of Denmark didn’t seem to think so. The women gained official recognition that their cancer was an occupational illness when they succeeded in their bid for compensation.
Anything that disrupts the circadian rhythms of the body, such as jet lag, can impair a person’s ability to function and can impair their general well being. For instance, a person may feel exhausted or may want to sleep at the wrong times after he has been on a long distance flight.
If someone has a new baby and they are forced to get up several times a night, they can feel permanently tired and not able to concentrate the next day. So far, though, nothing more than that has been known about the effects of disrupted sleep patterns.
Studies to date have demonstrated a plausible hypothesis for how cancer could occur as a result of disrupted sleep. Animals with disrupted circadian rhythms developed cancer but they are anatomically different from human beings and scientists don’t know if their findings can be applied to humans.
Although the connection between shift work and cancer has not been established, authors of the latest study say that shift work should be altered and made more human friendly because of scientific discoveries of its possible link to cancer, carried out by occupational medicine and chronobiology departments.
Source: Thomas C. Erren, Puran Falaturi, Peter Morfeld, Peter Knauth, Russel J. Reiter, Claus Piekarski. Shift Work and Cancer: The Evidence and the Challenge. Deutsches Ärzteblatt International, 2010; 107 (38): 657-62 DOI:
Joanna is a freelance health writer for The Mother magazine and Suite 101 with a column on infertility, http://infertility.suite101.com/. She is author of the book, 'Breast Milk: A Natural Immunisation,' and co-author of an educational resource on disabled parenting, in addition to running a charity for people damaged by vaccines or medical mistakes.