In the immortal words of the late, great Warren Zevon, "Life'll kill ya." But this time, it's personal . As has just been widely reported in the media , the World Health Organization's cancer research organization is about to add working night shifts to its list of probable carcinogens. Why? Because working at night switches the body's exposure to light and darkness, disrupting the natural circadian rhythms, and interfering with natural production of the hormone Melatonin, which can suppress development of tumors. Of course, I work nights a lot . This wouldn't be such a concern, except that the place I work nights restricts my hours because letting me work more hours would lead to them being required (by state law) to offer me a health insurance plan. So... work that probably causes cancer, combined with an employer determined to not offer health insurance. Great, huh? Interestingly, the same thing can happen with Melatonin