Night-Shift Work, Melatonin Deficiency Linked to Colorectal Cancer Night-shift work may greatly increase your risk of developing colorectal cancer, according to data from the ongoing Nurses’ Health Study. In their study of nearly 80,000 female nurses, researchers at Brigham and Women’s Hospital in Boston, MA, found that those women who worked night shifts at least three times a month for 15 years or more were 35% more likely to develop colorectal cancer.* The researchers believe that melatonin deficiency may be the culprit, as environmental light decreases the release of melatonin in the body, which usually peaks in the middle of the night. “Melatonin has well-established anticarcinogenic properties, and a link between light exposure at night and cancer risk through the melatonin pathway could offer one plausible explanation for the increased risk we observed,” they wrote in the Journal of the National Cancer Institute. Several studies have already demonstrated a link between night-shift work and breast cancer. Moreover, previous research has supported the link between melatonin deficiency and the development of colorectal cancer. “The finding that colorectal cancer patients had plasma levels of melatonin lower than healthy control subjects suggests a possible link between low melatonin levels and the enhanced development of colorectal cancer in humans,” stated the researchers. References * Schernhammer ES, Laden F, Speizer FE, et al. Night-shift work and risk of colorectal cancer in the nurses’ health study. J Natl Cancer Inst. 2003 Jun 4;95(11):825-8. Thanks to Life Extension Institute www.lef.org Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.