Sleep and Cancer

The effects of chronic sleep deprivation, sleep interruption, and irregular sleep patterns have been linked to the leading causes of firefighter deaths. Recurrent sleep loss has not only been correlated with heart attack, suicide, and metabolic disorders but also to cancer. Consider the following medical research on cancer in regards to sleep deprivation and the viable options to improve sleep within the means of the firefighter schedule and demands of the fire service.

Our circadian rhythm, the controller of our sleep patterns is dictated by the 24-hour cycle of light and dark.  Melatonin is the primary sleep hormone produced by the pineal gland and is secreted in response to darkness. Disruptions to sleep at night, paired with exposure to artificial blue lighting from fluorescents, screens and light pollution on scenes of a call causes a false biological response: it suppresses the body’s circadian function to elevate melatonin levels in the evening for normal sleep. Suppressed melatonin levels are linked to cancer. Recent studies show that low melatonin levels are associated with significantly elevated risks of breast and prostate cancer. The International Agency for Research on Cancer (IARC) classified shift work with circadian disruption as a probable human carcinogen placing it in the same risk class as, e.g., ultraviolet radiation, benzo(a)pyrene, and acrylamide.

What is melatonin’s role beyond sleep? Melatonin has an estrogenic effect, it prevents the age-related inflammatory response and also plays a critical role in endocrine function. There is mounting evidence that the sleep hormone is directly related to immunity, prevention, and survivability of cancer. Melatonin “inhibits tumor growth and cancer metastasis” (Melatonin and cancer, NCBI 1). During the last 20 years, melatonin has been studied as concurrent supplementation alongside chemotherapy treatments for cancer patients. The studies unanimously found that “melatonin increases the mean survival time and reduces the toxic side effects of chemotherapy. Melatonin significantly improves complete and partial remission as well as the one-year survival rate by around 50%” (International Journal of Cancer and Clinical Research).

The call to action is now. Fire Departments nationwide should be actively responding to improve sleep conditions. Here are four tips to begin immediately that will improve natural levels of melatonin, thereby decreasing risk for cancer within the fire service:


  1. Protect the eyes; mandatory use of blue-blocker glasses at night
  2. Download blue blocking apps for department technology devices & screens
  3. Install red lights in the firehouse, these are least disruptive to circadian rhythm
  4. Promote a culture that supports sleep hygiene and eating for healthy melatonin levels (dietary recommendations taught in the First Responder Sleep Recovery Program™)


There is a growing necessity for implementing a sleep recovery training to lower the risk of cancer, and other deadly health issues for those in the fire and emergency services. Contact Jacqueline Toomey at (720) 347-0269 or for more information on bringing the First Responder Sleep Recovery Program™ to your department.