Not getting adequate sleep (particularly, at night) is now recognized as a risk factor for cancer. It seems that the preponderance of studies suggest that getting at least 6-7 hours of night time sleep is protective against cancer (as well as diabetes, heart disease and obesity.) Additionally, new studies have found that getting interrupted sleep is also increases the growth of cancer.
Scientists hypothesize that this increased risk could be due to light exposure at night (i.e. night-shift work, looking at a brightly-lit computer screen in bed at night, etc.), which disrupts the body’s normal time clock (circadian rhythm.)
In fact, the International Agency for Research on Cancer has recently classified shift-work that causes circadian disruption as “probably carcinogenic” to humans (a cancer-causing risk factor.)
Not Getting Enough Sleep Encourages Cancer Growth:
First: When you don’t get enough sleep (or have light exposure at night), your brain releases smaller amounts of the powerful hormone, melatonin. This hormone is normally produced at night, but its production is suppressed when you are exposed to light at night. Researchers believe that the increased risk of cancer may be related to decreased melatonin levels. Melatonin increases the production of other hormones, such as estrogen, and scavenges free radicals and boosts the production of other antioxidants in the body.
- It seems that exposure to blue wavelength light is the worst culprit in disrupting melatonin production. Blue wavelengths are especially prominent in computer screens, television screens and energy-efficient lighting (i.e. fluorescent lightbulbs and LED lights.)
- The editors of the Harvard Health Letter make the following recommendations:
- Use dim red lights for nightlights. Red light has the least power to shift circadian rhythm and suppress melatonin.
- Avoid looking at brightly lit screens beginning two to three hours before bed…I’m very guilty of this 🙁
- If you work a night shift or use a lot of electronic devices at night, consider wearing blue-blocking glasses. (Check out this site to learn more about blue-blocking glasses and the science behind it. FYI-We do not get any commission from them.)
Read more about melatonin and cancer on our IOE blog
Second: Sleep deprivation increases the levels of the stress hormone, cortisol, which stimulates tumor growth, metastases (tumor cell spread), angiogenesis (blood vessel growth) and reduces tumor cell apoptosis (cell death.)
Read more about stress, stress hormones and cancer on our IOE blog
Third: People who don’t get enough sleep have more systemic inflammation, which impairs immune function (weakening a key defense mechanism against cancer) and stimulates insulin resistance (increasing obesity and estrogen levels), tumor growth factor production, increased oxidative stress (free radicals) and impaired DNA repair.
Read more about inflammation and cancer on our IOE blog
Not Convinced? …The Data Are Compelling
Here are some slides from one of my recent integrative oncology talks:
Dr. Lawenda’s Secret To Better Sleep:
One of the best, completely drug-free and 100% natural ways to get my patients to fall asleep more quickly and stay asleep is through meditation.
If you are not a meditator, no worries. It is very easy to do using a pair of headphones and a music player. You will need to buy and listen to a high-tech soundtrack embedded with a technology called “brainwave entrainment” (BWE) that within 15 minutes will put your brain in a state conducive to optimal sleep. The BWE product I highly recommend to all my patients is called Sleep Salon.
Sleep Aid Supplements:
If you are looking for supplements for helping you sleep better, these are some of the ones I have found work the best (I recommend you only take 1-2 at a time to see what works best for you…and always discuss with your physicians before using them):
- Relaxed Wanderer 2 oz: take 10 drops (morning, noon and evening)
- CatecholaCalm 90 caps: take 1 capsule (morning, noon and evening)
- SAMe (S-Adenosylmethionine) 60 caps: take 1-2 capsules (morning, noon and evening)
- Valerian Root Max-V 60 caps: take 1-2 capsules (morning, noon and evening)
- Neurolink 180 caps: take 2 capsules (morning, noon and evening)
The Bottom Line:
Getting adequate sleep means different things to each of us. Some of us get by on less sleep than others. Some folks are night owls, while others need to get to bed early.
The science of sleep, circadian rhythms, melatonin production, exposure to light at night and the association with cancer risks are all areas of active research. We don’t know for certain whether any of these factors are absolutely connected with the development, growth and progression of cancer.
That said, in the presence of mounting data supporting these associations, I recommend that you play it safe. Try to get at least 6-7 hours of sleep, minimize your exposure to light at night…and meditate before bed.
Additional References:
How to Sleep Better: Tips for Getting a Good Night’s Sleep (one of the better articles I’ve read on tips for improving your sleep)
Twelve Simple Tips to Improve Your Sleep (Division of Sleep Medicine, Harvard Medical School)
Cheating Ourselves of Sleep (New York Times, June 17, 2013)
Steps For More And Better Sleep (New York Times, June 24, 2013)
Not Getting Enough Sleep Makes You Eat More Fat and Calories (Motherboard)
