Can Good Sleep Prevent the Spread of Cancer?
Much has been made about the importance of getting adequate, quality sleep in order to prevent the onset of cancer. Sleep deprivation, by any means, has been shown to amplify one’s risk for cancer due to disruptions to general body homeostasis, but also because it can negatively impact the immune system.1 Once a cancer diagnosis is logged, sleep continues to be somewhat evasive, for a number of reasons:
- Anxiety about the diagnosis, of course, is a big sleep disruptor
- Treatments for cancer also have their own adverse impacts on nighttime sleep and daytime alertness.2,3
- Pain and side effects can dismantle even the best efforts to get enough sleep.
- Cancer is linked to circadian rhythm disruptions, which can further entangle one’s sleep rhythms, turning daytime fatigue and insomnia into uninvited guests who never leave.4
Recent research continues to drive home the importance of sleep as a way to slow down cancer’s progress, however.
Nighttime light and metastasis
A recent study presented at the Endocrine Society’s annual meeting last March in New Orleans points to dim-light exposure as a potential reason why breast cancer may metastasize—or spread—to the bones.5 Metastasis is the process that allows cancer cells to mobilize and detach from their original tumors to invade separate tissues and develop even more tumors. 9 out of 10 deaths caused by cancer are related to metastasis.6
Study author, Dr. Muralidharan Anbalagan of Tulane University School of Medicine, wrote of nighttime light exposure and metastasis that: “This is important, as many patients with breast cancer are likely exposed to light at night as a result of lack of sleep, stress, excess light in the bedroom from mobile devices and other sources, or night shift work.” This circadian factor was studied in mouse models, but this study suggests it might be possible for humans to inhibit the spread of cancer to the bones through what Anbalagan described as an “intact nocturnal circadian melatonin anti-cancer signal.”
Low pH, sleep, and aggressive tumors
Separate research suggests that “tumor acidosis” may signal cancer cells to more aggressively develop and spread. Low pH (acid) conditions can bolster the gene expression of certain molecules that perform cell migration and invasion, according to study author, Dr. Nazanin Rohani.6
Rohani’s team found that acid regions were found on the surfaces of tumors—where they connect to other tissue—as well as in pockets inside the tumors. While this study didn’t investigate sleep’s role in low pH conditions, specific kinds of sleep disruptions are well known for lowering one’s pH, leading to something referred to as metabolic acidosis7:
- Sleep apnea, which leads to low levels of cellular oxygenation and high levels of cellular carbon dioxide (acidosis)8
- Insomnia, which leads to inflammatory responses that can create an acid environment where tumor cells might thrive9
In chronic sleep disorders, oxidative stress is caused by neurochemical imbalances which pave the way for an acid-base disturbance that could open the door to potential cancerous growth.10 It’s not a stretch to see how untreated sleep disorders—especially cancer’s favorite bedfellow, insomnia—might contribute to the spread of tumors.
Are you sleep deprived?
There are few, if any, people with a cancer diagnosis who don’t also struggle with sleep. Some signs of sleep loss to pay attention to include:
How to sleep when you’re dealing with cancer
Striving for enough good sleep should be a goal, but with this caveat: some days and nights will be better than others. Don’t beat yourself up if you aren’t getting eight perfect hours, seven nights a week. Do celebrate when you manage to sneak in a nap or have a restful night’s sleep.
Here are some sleep tips to consider as you work through the maze of cancer treatments, tests, symptoms, and medication side effects.
- Practice good sleep hygiene, such as keeping to a regular sleep-wake schedule; making your bedroom sleep-friendly (quiet, dark, cool, clean, comfortable); putting away electronics at bedtime; and avoiding alcoholic beverages or cigarettes at bedtime and caffeine after lunch.
- Don’t stress if you can’t sleep; losing sleep oversleep loss (“orthosomnia”) isn’t productive. Find ways to relax, instead, like knitting or reading or listening to music. Rest, even without sleep, is still better than stress.11
- Exercise in the light of day. It doesn’t need to be a high impact or hard. A walk every morning can strengthen circadian rhythms.
- Talk to your doctor about your sleep problems; they may be able to help you with medications or nondrug therapies.
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