Disruptions in One’s Biological Clock Can Increase the Risk of Breast Cancer

Sara Robb and Chunla He

A new study by scientists at the University of Georgia finds the disruptions in a woman’s circadian rhythm or biological clock can lead to an increased risk for breast cancer. Specifically, the study found that increased exposure to artificial light sources leads to a higher risk of developing breast cancer. To avoid disruptions to a woman’s biological clock, the authors suggests that working at night should be avoided if possible and women should adjust sleep patterns so that they align more with traditional hours corresponding with natural light and dark.

“Exposure to artificial light leads to a significantly higher risk for developing breast cancer,” says Chunla He, a graduate student in biostatistics and lead author of the study. “People naturally secrete the hormone melatonin, which helps to regulate the circadian rhythm. When the sleep-wake cycle is disrupted by artificial light, melatonin secretion is adversely affected.”

Sara Wagner Robb, a co-author and an assistant professor of epidemiology at the university’s College of Public Health, adds that “scientists are becoming increasingly aware of the health risks associated with night workers and others exposed to circadian-disrupting behaviors.”

The article “Circadian Disrupting Exposures and Breast Cancer Risk: A Meta-Analysis,” was published in the September issue of the International Archives of Occupational and Environmental Health. It may be accessed here.