Many people nowadays struggle with sleep – getting to sleep, staying asleep or both – but people undergoing cancer treatment tend to be particularly affected by sleep problems.
The causes vary. Insomnia may be due to anxiety, depression, pain, restless legs or side effects from cancer treatment. In turn, insomnia can worsen other cancer-related conditions and symptoms, such as pain, fatigue, depression, or anxiety, thus creating a vicious cycle.
Many studies suggest that getting less than 6.5 hours of sleep each night increases our risk of cancer (as well as type-2 diabetes, heart disease, Alzheimer’s disease and obesity). And even if you’re sleeping but having fragmented sleep (sleep marked by frequent awakenings), this may make cancer more aggressive and invasive by weakening the immune system, studies have found.
There are many hypotheses for why a lack of sleep might increase our cancer risk. One is that light exposure at night which disrupts the body’s innate body clock (circadian rhythm), which in turn throws off our cancer defense system. Indeed, the International Agency for Research on Cancer has recently classified shift-work that causes circadian disruption as “probably carcinogenic” to humans.
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.
Blue Wavelength Light Ruins Sleep
Research has proven that when your eyes are exposed to blue wavelength light, the natural night time production of melatonin is markedly suppressed. Melatonin is required for induction of sleep and staying asleep through the night. Blue wavelengths are especially prominent in computer screens, television screens and energy-efficient lighting (i.e. fluorescent lightbulbs and LED lights).
Tips for reducing blue wavelength light exposure:
- Use dim red lights for nightlights. Red light has the least power to shift circadian rhythm and suppress melatonin.
- I recommend changing out our bedside table bulbs with amber colored bulbs.
- Avoid looking at brightly lit screens (TV, computer, smart phone) beginning two to three hours before bed.
- If you work night shifts or use a lot of electronic devices at night, consider wearing blue-blocking glasses (Two of my favorites: Swanwick, Felix Gray).
- Alternatively, you could install a blue light filter on your devices. I use a computer screen filter called f.lux that’s free and super simple to download and install.
Not Getting Enough Sleep Increases Cortisol and Suppresses Immunity
In addition to light at night, another way in which sleep disruption may drive cancer is via our hormones. 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.) High cortisol also causes insulin resistance and obesity.
Finally, people who don’t get enough sleep have higher levels of inflammation, which can impair immune function (weakening a key defense mechanism against cancer) and stimulates tumor growth factor production, increased oxidative stress (free radicals) and impaired DNA repair.
One study found that getting only 4 hours of sleep at night (just one night), reduced natural killer (NK) cell activity to an average of 72%, compared with NK cell activity in participants who had a full night’s sleep (REF). Research indicates that NK cells have a substantial role in killing tumor cells.
Alzheimer’s disease and Poor Sleep
Research suggests that chronically getting too few hours of sleep (<6 hours per night) may increase your risk of Alzheimer’s disease and dementia (REF, REF). Alzheimer’s disease is characterized by the presence of amyloid plaques and tau tangles in the brain. Previous studies suggested that poor sleep quality was associated with the presence of amyloid plaques in cognitively healthy individuals (REF), and that even one night of sleep deprivation can increase the levels of amyloid in the cerebral spinal fluid (CSF), the fluid that bathes the brain (REF). Another study suggests that poor sleep may also be associated with increased brain levels of tau (REF).
In a small study, of healthy individuals (age 30-60) who had one night of good sleep and one night of sleep deprivation, sleep deprivation increased CSF levels of tau by over 50%. This increase was correlated with an increase in amyloid after sleep deprivation (REF).
First described in 2012, the glymphatic system may explain how the brain clears excess waste products and reduces the risk of developing dementia when functioning properly. It consists of a brainwide pathway that moves waste from the brain tissue into lymphatic vessels. Inadequate or disrupted sleep decreases lymphatic flow, leading to an accumulation of amyloid and tau. The latest data seems to indicate that non-REM deep sleep is the most important type of sleep for stimulating lymphatic flow (REF).
Sleep Tracking Devices
I often recommend the use of sleep tracking technology to get a better handle on the amount and quality of sleep his patients are getting. There are many different commercially available devices on the market, but his favorite is the Oura ring. This unobtrusive device is worn on a finger while sleeping to track sleep time, quality, heart rate and heart rate variability (a measurement of stress) and body temperature. If worn during the day, it also tracks activity.
I find that knowing about the quality and duration of your sleep helps to guide lifestyle changes, and informs on the potential reasons for sleepiness, insulin resistance and stress.
IOE’s Top Tips to Improve Your Sleep
- Rule out dental or breathing problems: If you wake up feeling unrefreshed and/or are frequently tired during the day, your sleep may be getting disrupted by sleep apnea, bruxism (tooth grinding) or other imbalances you may not be aware of. These are very common causes of poor sleep that can easily be tested for. Discuss this with your doctor or dentist; they may prescribe a sleep study for you.
- Spend time outdoors every day. Daylight exposure stimulates the pineal gland in your brain. This gland triggers the production of melatonin which helps regulate your circadian rhythm and the production of reproductive hormones. It’s also a powerful antioxidant. To function properly, the pineal gland needs daily exposure to daylight (without sunglasses). That doesn’t mean staring into the sun, but simply “being outdoors” (maybe walking, making phone calls, eating lunch outdoors, or even just sitting on a patio chair, meditating or reading during daylight hours (pretend you’re a Mediterranean!). If we are never, or rarely, outdoors, our body clock gets confused and this affects not only our wake-sleep cycle, but our nervous system and brain, hormonal regulation, muscle function and immune health, too.
- Please read this excellent article about the brain benefits of sunlight by sports physiologist and nutritionist Dr. Phil Maffetone. We recommend that you spend at least 1 hour a day outdoors (preferably before noon) – wear a brimmed hat to shield your eyes if the sun is too bright. (Did you know that you can also use light box or light therapy glasses to get the same benefits without exposure to bright sunlight? Studies show that you can improve your sleep quality by using light therapy for 30-90 minutes upon awakening each morning to help reset your circadian cortisol rhythm.
- Dr. Lawenda’s favorite light therapy device are AYO light therapy glasses).
- Physical activity during daylight hours; 20 to 40 minutes, ideally outdoors (see previous bullet point). Don’t exercise after dark, except calming activities such as yoga, tai chi, etc.
- No caffeinated drinks after 1pm, stop earlier or avoid altogether if desired sleeping rhythm isn’t achieved.
- Free your mind by planning: Before finishing work for the day, write down on a blank piece of paper the most important meetings/appointments for the next day. This will reduce the amount of work-related fretting you do at home when you should be relaxing.
- Only moderate amounts of alcohol during dinner, e.g. 1 glass of wine for women, 2 glasses for men maximum. Although alcohol makes most people feel sleepy initially, it often stimulates them a few hours later and disrupts their sleep. It is also associated with a higher incidence of hot flashes, which can wake you up and disrupt your sleep.
- Eat a well-balanced dinner, e.g. roughly 35% fat, 30% protein, 35% low-glycemic carbohydrates. The brain needs all three macronutrients to produce melatonin. Moreover, eating a macronutrient-balanced meal can help prevent blood sugar slumps or spikes during the night, which are a common cause of nighttime waking. If you eat dinner early, eat a balanced snack before bedtime, for instance an apple or wholegrain cracker with peanut butter.
- Switch off all phones, radio, TV etc. before dinner; quiet, relaxing music is OK. Have dinner sitting at a table, eating slowly and paying attention to what – and how – you are eating. Say Grace before dinner, go through a round of “thankfulness” with your fellow-diners, or simply observe a minute’s silence before you start eating. (Read this article about the health benefits of pre-meal prayer.) Avoid stressful topics of conversation. All this not only aids digestion and absorption; calm, mindful eating can help lower your overall stress levels and help you sleep better.
- A short walk around the neighborhood after dinner – alone, to clear your thoughts, or with your partner, to recap on the day’s events and reconnect; 10 minutes is all that’s needed. This can also lower your postprandial blood sugar levels; a study published in the December 2016 issue of Diabetologia found that 10 minute post-meal walks brought about decreases in blood glucose levels of 22%.
- Minimize or eliminate being in front of a screen 60 minutes before desired sleeping time; read a book or magazine printed on paper, rather than a laptop, phone or electronic tablet.
- Data-dump (30-60 minutes before bedtime): Quickly write everything that’s currently on your mind onto an empty page of A4 paper and fold it up. This is not a to-do list; it’s simply a place where you can “park” your thoughts and/or worries so that you can take a break from them for a few hours.
- Gratitude journaling: Every evening, spend 5 minutes (or more) writing three things (or more) that you are grateful for into a “gratitude journal.” They can be big or small, new or repeated from previous days. E.g., my health, my cozy home, my family’s health, my job which I enjoy and/or which helps pay the bills, my health insurance, the nice man at the supermarket who handed me the glove I had dropped, the purring cat on my lap, the flowers in my yard, etc. Focusing on the positive things in our lives – sometimes forcing ourselves to dredge them up at the end of a stressful day – allows us to take a step back from our day-to-day worries and feel more positive about our lives and more optimistic about the future, thus reducing scope for nighttime rumination.
- Mobile phone switched off at least 60 minutes before desired sleep time, put in a drawer in a room that isn’t the bedroom.
- Bedroom as dark and quiet as possible; black-out blinds (esp. during summer when the sun rises early), no LED lights, no lights on alarm clocks. Replace ticking alarm clocks with noiseless ones. Do not fall asleep to the sound of a switched-on TV or radio set; their “white noise” may feel reassuring as you drift off to sleep but will prevent you from attaining deep sleep and wake you up during the night.
- Comfortable bedding: Considering you spend about 1/3 of your life in bed, you owe it to yourself to use the highest-quality bedding you can afford.
- Invest in a high-quality mattress (mattress needs are very individual and vary from one person to another; research this carefully and negotiate with your partner; where spouses have different comfort needs, consider buying in a bi-comfort mattress where one side is softer than on the other). Maintain mattress in accordance with manufacturers’ recommendations (regular airing, turning, replacing after a specified number of years, etc.). Click here to read the Consumer Report guide to choosing a mattress. You might even consider transitioning off traditional mattresses completely and shifting to a more “back-to-nature” style of floor sleeping championed by biomechanist Katy Bowman as part of a movement-rich way of life to help counteract the sedentary habits of modern life. (Watch the excellent video on this page explaining the role of biomechanics in human health.)
- Get a pillow that supports your head and neck adequately; again, individual needs vary, so get professional advice on the best pillow for you. Some even keep your head cooler.
- Sleep in breathable cotton sheets that can be washed at hot temperatures; use comforters or blankets that can be hot-washed (this helps reduce dust mites and other potential allergens).
- Use seasonally appropriate bedding; lighter in the summer, warmer in winter – so you don’t wake up because you’re too hot or too cold. During transitional seasons use layering to allow you to add or shed a layer of warmth without having o get out of bed.
- Evict pets from your bed. Sleeping snuggled up to an adoring pet can feel wonderfully comforting, but if your four-legged friend starts to encroach on your space or wake you up at night, you may need to set some boundaries. Try to train your pet to sleep on the floor, in a basket or crate next to your bed, or, if they won’t comply with this, shut them out of your room at night.
- If you get into bed and cannot fall asleep after 20 minutes, get up and return to another space in the house to do a relaxing activity, such as reading or listening to music. Lying in bed awake can create an unhealthy link between your sleeping environment and wakefulness. Instead, you want your bed to conjure sleepy thoughts and feelings only.
- Wake up at the same time every day. Even if you have a hard time falling asleep and feel tired in the morning, try to get up at the same time (weekends included). This can help adjust your body’s clock and aid in falling asleep at night.
- Avoid naps if possible. When we take naps, it decreases the amount of sleep that we need the next night (Did you know that each of us needs a certain amount of sleep per 24-hour period? We need that amount, and we don’t need more than that). Napping may cause sleep fragmentation and difficulty initiating sleep, and may lead to insomnia and sleep deprivation.
- Other disruptive bed mates. If your partner is a noisy or restless sleeper, this can have a deleterious effect on your own sleep and health, and on your relationship as a couple. A short-term solution can be to seek refuge in another, quiet bedroom. This is not a happy long-term solution for most people, however. Investigate the causes of your partner’s sleeping patterns and address them, where possible. (E.g., if they snore, should they have a sleep study to investigate possible sleep apnea? If they get up to go to urinate frequently at night, should they reduce the amount of liquids they drink in the evening, or might they have a medical condition that warrants a visit to a urologist?)
- Keep your room cool; For optimal sleep, specialists recommend a room temperature of between 60 and 67 degrees Fahrenheit. Your body temperature needs to drop to initiate good sleep. Temperatures that average in the 60’s force your body to produce more melatonin, which facilitates falling and staying asleep.
- One of the biohacking devices I often recommend for patients is a mattress pad that circulates cool water (as low as 55 degrees F) through a pump/cooling unit, called the Ooler Sleep System.
- Take a warm bath, shower or sauna before bed: a warm bath, of around 104-109 degrees fahrenheit, for as little as 10 minutes can significantly improve overall sleep efficiency (more time spent in sleep rather than trying to fall asleep). Doing this 1-2 hours before bedtime can also speed up the time it takes to fall asleep by about 36% (REF).Exposing our skin to heat causes our body to bring a large amount of blood flow to the surface. This blood flow brings the heat from the core to the surface, causing a drop in body temperature which is essential for quality sleep.
- Have low red-tone lights as night lights in the hallway and bathroom.
- Sleep apnea: If you or your sleep partner suspect that you might have sleep apnea (periods of not breathing in your sleep), this needs to be discussed with your primary care physician. This condition not only causes a disruption in sleep, but can lead to other serious medical conditions that may impact your heart, metabolic and brain health.
- Try Acupuncture
- Use Aromatherapy
- Do the “4-7-8 Breath Technique”
- This is one of the most powerful and effective relaxation techniques that you can do anywhere or anytime when you are feeling stressed. This is a paced breathing technique, adopted from a Yoga breathing practice (Pranayama), and was popularized by Dr. Andrew Weil (Director of the Arizona Center for Integrative Medicine at the University of Arizona.) Here’s how it’s done:
- Get into a comfortable position. I prefer to be in a seated position with my hands on my lap. You can also do this lying down.
- Press the tip of your tongue on the ridge of tissue just behind your top, front teeth, and keep it there throughout the breathing cycles.
- Breath in deeply through your nose for 4 seconds.
- Hold you breath for 7 seconds.
- Breath out slowly through your mouth for 8 seconds. As you exhale, you will be blowing the air around your tongue, which remains pressed on the ridge of tissue behind your front teeth.
- Repeat steps 3-5, three or more breathing cycles, in a row. You can gradually increase the number of cycles over the next few weeks. I generally do not do more than 10 cycles in a row. If you feel lightheaded, that’s normal when you are first starting out. This will pass as you get more comfortable with the technique and you body adjusts to it.
- I recommend that you do this at least 3-4 times per day.
- This is one of the most powerful and effective relaxation techniques that you can do anywhere or anytime when you are feeling stressed. This is a paced breathing technique, adopted from a Yoga breathing practice (Pranayama), and was popularized by Dr. Andrew Weil (Director of the Arizona Center for Integrative Medicine at the University of Arizona.) Here’s how it’s done:
- Listen to Brainwave Entrainment/Binaural Auditory Beats Soundtracks. This technology relies on presenting separately to each ear two tones that slightly differ in their frequency. The user must listen to these tracks while wearing headphones or earbuds. Studies show that binaural beats can reduce anxiety, pain (REF) and improve sleep (REF).
- Brain Evolution Systems is what I use and recommend for patients who want a passive method to reduce stress in the brain, and subsequently the body. This is a 6-soundtrack program. You listen to each one for 30-minutes, 1-time/day, for one month. Then after 1-month, you move onto the next soundtrack. So, you get 6-months of soundtracks. After that, you just listen to whichever soundtrack you want of the 6 (I place them on random selection). This is the highest quality of the products in the binaural beat market.
- Learn Cognitive Behavioral Therapy for Insomnia. Also known as CBT-I. This is considered one of the most effective approaches for improving sleep. CBT-I is a structured program that helps you identify and replace thoughts and behaviors that cause or worsen sleep problems with habits that promote sound sleep. Unlike sleeping pills, CBT-I helps you overcome the underlying causes of your sleep problems. The cognitive part of CBT-I teaches you to recognize and change beliefs that affect your ability to sleep. This type of therapy can help you control or eliminate negative thoughts and worries that keep you awake. The behavioral part of CBT-I helps you develop good sleep habits and avoid behaviors that keep you from sleeping well. A CBT-I trained therapist will coach you through this program. This can be done in-person or remotely (i.e. telemedicine).
- One of my favorite CBT-I programs is called Go! to Sleep, Cleveland Clinic’s clinically developed, 6-week online course for improving sleep, which can be done entirely in the comfort and privacy of your own bedroom.
- Get a Massage
- Practice Meditation
- Mindfulness meditation involves focusing on your breathing and then bringing your mind’s attention to the present without drifting into concerns about the past or future. It helps you break the train of your everyday thoughts to evoke the relaxation response, using whatever technique feels right to you.
- Guided meditation: Guided sleep meditation is a method for helping you to let go of worrying thoughts and relax your body before bed. Like other forms of meditation, this practice involves moving your focus away from your mind to sensations in your body. Regular practice of guided sleep meditation has been shown to improve sleep.
- My favorite online meditation apps which incorporate this approach are Waking Up, 10 Percent Happier, Calm and Headspace.
- Practice Yoga
- Get Professional Help: If you are plagued by persistent emotional problems or anxieties that are keeping you up at night, consider working with a psychologist or coach that specializes in sleep problems.