Have I mentioned how important sleep is? Just another reason to catch enough shuteye–researchers have found that shift work (work that can disrupt normal sleep patterns like firefighting or long rounds in emergency rooms) can actually cause cancer by repeatedly disturbing the body’s internal clock. The internal clock is responsible for regulating circadian rhythms, a complex mechanism involved in many body functions including hormonal and neurological balance.
The study was carried out by the International Agency for Research on Cancer, the French-based cancer agency of the World Health Organization, which looked at several studies showing the links between shift work and cancer. In one study, it was found that women who work night shifts may have a 60 percent greater risk of developing breast cancer. In another study, tests in mice showed that circadian clock genes are disrupted in tumor cells. And in yet other studies, evidence shows that firefighters, who breathe in smoke, chemicals and dust and who also work shifts, have a higher risk of cancer and heart disease.
Scientists believe that the culprit in the cancer susceptibility may be the body’s response to light. The brain’s pineal gland produces melatonin, a hormone necessary for regulating the internal clock, and which also acts as a cancer fighting anti-oxidant. When repeatedly subjected to light and sleep deprivation, the body’s normal melatonin production is disrupted, which can lower the protective and balancing effects of melatonin.
Careers that are primarily shift work include firefighting, health-care, industrial, transportation, communications, and hospitality. I’d also like to point out that regular late-night partying with stimulants and narcotics would also fall under the category of extreme shift work. The agency stresses, though, that these findings are preliminary, and that it would take another five years to understand the situation fully and what can be done about it.
Shift work is going to be with us forever. Some jobs just require round-the-clock availability, period. However, it’s important to get the sleep while you can. If you’re a shift worker, then you’ve got to try to get your seven to eight hours consecutively and consistently. These finding may help employers manage shift schedules more effectively, helping their employees, and their businesses, in the long run. Until then, try to get used to a regular sleep routine within the constraints of your work schedule–it’ll save you years of exhaustion, or worse.