Cancer of all kinds have plagued humanity for some time, which is why researchers are working so hard to determine risk factors, treatments, and possible cures. Breast cancer in particular has received a lot of attention because of its devastating effects on women. Now, it seems that working the night shift may add one more risk factor for women when it comes to developing breast cancer.
Currently, breast cancer kills more women than any other cause and more than 1.3 million women are diagnosed with it each year. Researchers have discovered possible risk factors like genetic mutations, late first pregnancies, and hormone therapy. Environmental and lifestyle causes are also being explored, but have not yet been specifically identified. In France though, a study by the Center for Research in Epidemiology and Population Health looked at the careers of 3000 women and compared their breast cancer rates. Shockingly, they found that women who worked the night shift were 30% more likely to develop breast cancer. They believe this may be due to the disruption of the sleep cycle and circadian rhythms. These processes, when disturbed, can negatively affect the nocturnal melatonin surge and its anti-carcinogenic effects, functioning of the biological clock genes that control cell proliferation, and/or the immune system. Women who worked swing shift, switching on and off of at least three days of night shifts at a time, were even more likely to develop breast cancer than those who worked all night hours for each work night.
At a time when so many women suffer from breast cancer and when night work is on the rise, this study shows us yet again how important quality sleep is on a regular basis. If you do have to work the night shift, make sure you have at least eight hours of time in a dark room to rest, where light does not disrupt your melatonin release. It is imperative that we all take the time to recharge our bodies and minds, even if we feel we should be up and interacting with our families while they are awake. When you work at night, both you and your family need to understand the health risks of not allowing yourself that sleep. If you can sleep, you will enjoy many more healthy years with your family in the future than if you deny yourself that rest now.
- Yvonne S. Thornton, M. D., M. P. H.