Cancer is a big area of medical research right now as both a growing concern but also a a major growth industry in the emerging biodrug industry. Along with investigating ways to treat and, hopefully eventually cure, cancer, researchers are also learning about different causes of cancer. This, of course, can help many of us to implement new behaviors and lifestyle choices to reduce our cancer risks.
For example, a study from Harvard Medical School recently found there is an association between where you live—and your exposure to natural and artificial light—with breast cancer risk. The study found that higher amounts of ambient nighttime light can slightly increase the odds for developing breast cancer, among younger women who also smoke.
In a Harvard news release, study author Peter James—who is also the Harvard University Pilgrim Health Care Institute assistant professor of population medicine—said, “In our modern industrialized society, artificial lighting is nearly ubiquitous. Our results suggest that this widespread exposure to outdoor lights during nighttime hours could represent a novel risk factor for breast cancer.”
This research actually took into account earlier studies which suggests that high level of exposure to light during the night hours can disrupt the body’s internal clock (circadian rhythms). This, in turn, could reduce the presence/production of the hormone melanin, which can then lead to a higher risk of breast cancer.
Now, a large percentage of younger women do not necessarily have full control over the amount of nighttime ambient light exposure they get, but they can control whether or not they smoke. Still, Dr. Stephanie Bernik warns that these conclusions might be a little too early to have much merit.
She advises, “The findings in this study have to be taken with caution.” The Lenox Hill Hospital chief of surgical oncology goes on to say, “Although circadian rhythm disruption may be a factor in increasing the risk of cancer, it could be other factors related to working at night as well.”
For example, Dr. Bernik argues, “women who work night shifts may not eat well or exercise, both of which affect breast cancer risk. Also, the study found the risk greatest in smokers — which leads one to believe these women might not be living as healthy a lifestyle as the group that was sleeping at night.”
Overall, she says, the study needs “more insight as to the root cause of the increased rate of cancer in night owls is needed.”