Shift Work and the Link to Cancer
When I first moved to Houston in the mid-70′s, I took a job with a chemical company working shift work. I worked 12 hour shifts, 4 days on and 4 days off. Now you might think that having 4 days off sounds like a neat thing but it wasn’t.
First of all, when you’re working, that’s ALL you do. I can remember getting home and hardly having the strength to shower, eat, and then go to bed so I’d get enough sleep to get up early and do it all over again. When you’re working, there’s no “after work” time (or energy) to get together with friends, help your kids with homework, do yard-work, attend PTA meetings, or any of the other routine things that tend to come up during the week.
Secondly, shift work takes a serious toll on your mind. During the “graveyard” shift, time seems to stand absolutely still between the hours of 2 am and 4 am. I’d stare at the clock, work for what seemed 10 or 15 minutes, and then look at the clock again and I swear it hadn’t moved at all.
Lastly, your “4 days off” are not really 4 days off. You spend at least1, sometimes 2, days just trying to recuperate and catch up on your rest. Working shift work is really tough and according to a recent report, the downside of shift work just got a whole lot longer.
In June, a report coauthored by the American Cancer Society, the National Institute of Environmental Health Sciences, the National Cancer Institute, and the National Institute of Occupational Safety and Health (NIOSH) contained a list of 20 items identified as possible causes of cancer in humans. 19 of these items were chemicals or chemical compounds (including welding fumes and diesel exhaust). ”What was the last item,” you ask? Shift work.
So how does something like shift work cause cancer? According to the report (click here for links to the report), shift work disrupts your circadian sleeping patterns. OK, I knew that. By definition, when you’re working shift work, especially the evening and/or late shift, you work during the night and try to sleep during the day. But what’s the tie to cancer?
The key appears to be in the amount of the hormone Melatonin that your body produces. Melatonin is produced by a gland located in the brain. This hormone helps regulate sleep and is included in many sleep aids. It’s Melatonin that makes you drowsy so that your body can sleep and synchronize itself with its natural circadian rhythm. Melatonin is basically the synchronizer of our body’s internal clock.
Now, here’s the tie to shift work. Melatonin production is affected by light with that production being lowest during the day and highest at night. Working at night in a brightly lit office, factory, or warehouse inhibits the production of Melatonin. Trying to sleep during the day after working (or studying) all night usually results in low Melatonin production (because of the sunlight in your bedroom) making your sleep light, fit-full, and non-restful. The end result is that the immune system is weakened because your body is not getting enough sleep nor is it getting enough restful sleep.
But there’s more. Melatonin is also a powerful antioxidant. Reducing the amount of Melatonin produced by your body through shift work weakens your immune system even further making it easier for cancerous cells to take hold.
So the tie to cancer seems to be that shift work:
- Causes disrupted sleep patterns resulting in non-restful sleep which weakens the immune system
- Shift work lowers the natural production of Melatonin, a powerful antioxidant, weakening the immune system even further
A weakened immune system is not only more susceptible to cancer-producing agents, it can’t fight off the formation of cancerous cells that take root.
So what can you do if your job requires that you work shift work? Here are a couple of tips that I found while researching this topic:
- First and foremost, keep yourself in good health (and your immune system strong) by eating right and exercising regularly. Nothing else you do will benefit you as much as this one suggestion.
- Consider taking Melatonin supplements after you’ve worked a graveyard shift and before you go to bed. IMPORTANT: everything I’ve read suggests that LOW dosages (2-5 mg) are the most effective as well as the most safe. High dosages (greater than 5 mg) may be counterproductive and may have adverse effects including vivid dreams and lingering drowsiness. Note also that Melatonin is normally recommended for short term use only. See your doctor if you have doubts or questions about use or dosage.
- If you work late and must sleep during the day (or through the morning), keep your bedroom as dark as possible. That means rigging up some sort of “black out” curtain to block out as much sunlight as possible.
- Melatonin also helps to regulate body temperature so make sure the temperature in your bedroom is comfortable and slightly on the cool side.
- Try to keep your surroundings quiet. If you’ve got small kids like I did when I worked shift work, then good luck with this one. I still have fond memories of trying to sleep during the day with my kids making all kinds of noise as they played. My wife would yell at them to keep quiet because Daddy was sleeping. Ironically, it was my wife yelling that usually work me up. OK, so the memory is not so “fond” after all. One trick to try is to get yourself some kind of noise generator to play in the background to mask out most of the surrounding noise. There are “noise generator” or “background sound” apps for the iPhone and you can find CD’s and audio tapes that do the same thing. I’ve even seen alarm clocks with these features built in. Put one of those on before you go to bed and you’ll fall asleep to the soothing sound of ocean waves or rain falling in a primal forest. You’ll hardly hear the kids at all.
More and more research emphasizes the need for a good night’s sleep. It’s during this period of rest that our body strengthens, restores, and repairs itself. Key to this rest and restoration period is the production of Melatonin – and the key to that is darkness.
So, start rigging up those blackout curtains in the bedroom!