by Stephanie Eckelkamp
Chronic illnesses such as Lyme disease, fibromyalgia, ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome), and even long COVID can wreak havoc on health. Invading microbes, often at the root of these issues, can trigger inflammation and other processes that put your body’s cells in a state of stress and trigger a cascade of negative effects.
“Chronic illness is essentially chronic cellular stress — and when cells are stressed, they release chemicals that signal to the brain that something is wrong,” says Dr. Bill Rawls, MD, Medical Director of RawlsMD and Vital Plan. “This diverts resources away from routine bodily functions and activates the body’s fight-or-flight response, or sympathetic nervous system, which tends to raise hormones like cortisol and adrenaline that block sleep.”
While a large number of Americans, in general, suffer from some type of sleep disorder (33% to 50% for insomnia), people with a chronic illness are at elevated risk, with most experiencing circadian rhythm disruptions and poor sleep at some point in their recovery, according to Dr. Rawls. In fact, in one study of 600 fibromyalgia patients, a whopping 96% were considered “problem sleepers.” And this, unsurprisingly, can further exacerbate symptoms and impair healing.
The good news: Once you understand a bit about how your circadian rhythm works (and the factors that influence it), you can get it back on track and restore health-promoting sleep.
How Circadian Rhythms Impact Sleep and Health
Your body has a circadian biological clock (often referred to as your circadian rhythm or body clock), an internal mechanism that helps control various biological processes on a 24-hour cycle. It’s influenced by circadian clock genes in your cells as well as a group of neurons in the brain’s hypothalamus called the suprachiasmatic nucleus (SCN). The SCN responds to environmental cues, primarily light, to ensure certain bodily functions take place at certain times.
One of the most important processes controlled by your circadian rhythm is the sleep-wake cycle, i.e., when and how much you sleep over a day — and it does this by initiating the release of hormones that help you feel sleepy at night and alert during the day. According to Dr. Rawls, here’s what’s happening in a nutshell:
- When light enters our eyes in the morning, the SCN gets the cue that it’s time to be active. This triggers the release of hormones like adrenaline and cortisol from the adrenal glands. Cortisol then initiates the release of additional hormones that boost “daytime” cellular activities and primes you for greater physical activity and alertness.
- As the sun goes down, the SCN senses the decrease in daylight (as long as you’re not exposed to excessive artificial light), which lowers cortisol and increases melatonin secretion. Melatonin, or the “sleep hormone,” makes you feel drowsy and triggers additional hormonal shifts that help initiate sleep.
- The following morning when the sun rises, your SCN senses light, cortisol levels increase, and melatonin secretion is suppressed. This “resets” your 24-hour clock.
Your circadian rhythm helps align your sleep with the natural dark cycles of the day, establishing a consistent pattern of restorative rest. “Everything needs rest periods to survive and function optimally,” says Dr. Rawls. During rest periods, cells are in repair and recovery mode. “They’re undergoing processes such as autophagy in which they’re breaking down misfolded proteins, worn-out mitochondria, and damaged DNA and recycling them into new proteins and cell parts, which promotes optimal cellular functioning,” he says. Sleep is also important for the formation of long-term memories and metabolic regulation.
Regular rest periods are essential for everyone, especially if you’re battling a chronic health condition and already have suboptimal cellular functioning.
When Chronic Illness Messes with Your Circadian Rhythm
When everything runs smoothly, your sleep-wake cycle is relatively aligned with the dark and light cycles of the day, and you can typically fall asleep, stay asleep, and wake up in the morning without too much effort. The problem: Excessive cellular stress due to chronic illness — particularly when coupled with unhealthy habits like late-night screen time — can interfere with normal circadian hormone fluctuations and cause circadian misalignment, which can drive sleep issues like insomnia along with mood swings, altered metabolism, and impaired cell function.
“The continued fight-or-flight response triggered by cellular stress elevates adrenaline, which blocks sleep, and interferes with normal cortisol release,” says Dr. Rawls. “You end up with higher cortisol levels extending into the evening, which keeps your cells alert and robs them of the downtime needed for repair — and things start to break down in the body.” Psychological stress, common with chronic illness, can also drive this fight-or-flight response.
For example, artificial light exposure late at night signals to the body that it’s still daytime, which suppresses melatonin and keeps cortisol elevated, explains Dr. Rawls. Also, late-night eating signals your body that it’s time to work, not rest.
How to Reset Your Circadian Rhythm for Better Sleep
Routine is key for establishing a healthy circadian rhythm and getting quality sleep. Just think of how our ancestors lived: “They woke up with the sun, they foraged and hunted during the day or performed other jobs, ate until their bellies were full, sat around to relax and digest, and went to sleep when it got dark — and pretty much every day was the same,” says Dr. Rawls.
Modeling these ancient behaviors in a modern, realistic way can help curb stress and restore a healthy circadian rhythm. “Anything you can do to create sameness, routine, and balance will be beneficial,” he says. From morning to night, here are a few ways to do just that:
1. Get a Dose of Natural Light First Thing in the A.M.
If you’ve been up all night due to pain or another symptom, getting out of bed to start the day is probably the furthest thing from your mind. But exposing yourself to natural light within an hour of waking can help you immediately feel more alert by putting a halt to melatonin production. Plus, if you struggle to fall asleep at a reasonable bedtime, getting a dose of early morning light can help advance your circadian rhythm or body clock, so melatonin production occurs earlier in the evening, and you fall asleep easier. Try adding a morning walk or eating breakfast near a window to your daily routine to reap the benefits.
2. Try a Sunrise-Mimicking Alarm Clock.
Keeping your bedroom shades raised and using the sun as a natural alarm clock is a great way to align your circadian rhythm to the natural light and dark cycles of your environment — but it’s not always possible, depending on your schedule and where you live. That’s where sunrise alarm clocks come in handy. These emit a soft yellow light that slowly increases in brightness, suppressing melatonin production and gently rousing you awake.
3. Spend Time Outdoors in Nature.
Immersing yourself in nature (think: the woods, a beach, or even a lush park) has added perks beyond natural light exposure. Research shows that just 20-30 minutes of walking or sitting in a natural setting significantly reduces levels of the stress hormone cortisol. If mobility is an issue, even viewing nature scenes through a window could help lower cortisol. Remember, while cortisol is necessary for initiating essential cellular activities during the day, chronically elevated cortisol due to chronic illness and other stressors disrupts normal circadian rhythms and sleep. Timing your nature walk for the late afternoon or evening may be particularly helpful for sleep.
4. Keep Meal Times Consistent (And Don’t Eat Too Late).
Your body loves predictability on all fronts, including when you eat. A good circadian-friendly schedule:
- Eat breakfast, lunch, and dinner roughly the same times every day.
- Eat your bigger meals earlier in the day.
- Don’t eat too late in the evening (shoot for a light supper by 7 p.m., suggests Dr. Rawls).
Research shows that the body is best at digesting when it’s light out, while eating when you should be resting can disrupt normal circadian rhythm, sleep, and metabolism, as it signals to the body that it’s time to stay up and process the meal. Just keep in mind that you don’t want to go to bed ravenous either since that can also keep you awake, warns Dr. Rawls. To curb nighttime hunger, have a light, easy-to-digest snack like a banana.
5. Cut Off Your Caffeine Intake by 2 P.M.
Caffeine can ramp up levels of stimulating adrenaline and cortisol, and consuming it in the evening when you should be winding down has been shown to delay your circadian rhythm — making it more difficult to fall asleep. Research has even found that having caffeine six hours before bed can reduce sleep time by an hour.
To be safe, try cutting off your caffeine intake seven to eight hours before bedtime (around 2 or 3 p.m. if your desired bedtime is 10 p.m.). And if you drink coffee, Dr. Rawls suggests swapping it for green tea, which is lower in caffeine and contains l-theanine, an amino acid that buffers caffeine’s stimulating effect in the brain.
6. Do Your Workouts Before 4 P.M.
“Regular exercise helps normalize stress hormones and balance cortisol, which can support a healthy circadian rhythm and quality sleep,” says Dr. Rawls. If you can work out, don’t exercise too intensely, he advises, since overtraining can drive inflammation, elevate cortisol, and add to your cellular stress load. Be mindful of when you work out, too. One study found that people who exercised at 7 a.m. or between 1 p.m. and 4 p.m. advanced their circadian rhythm or body clock slightly. What does this mean? They shifted their sleep-wake cycle earlier and, as a result, had an easier time starting their activities earlier the following day than evening exercisers.
7. Take a Nap to “Zero” Your Stress Hormones.
If you feel depleted by 1 p.m. — which is understandable as your body tries to heal — don’t simply power through your to-do’s. “Taking a nap, even for five minutes, helps bring down stress that’s been building throughout the day and eases you into a more relaxed evening,” says Dr. Rawls. “I call it ‘zeroing’ my stress hormones.” Pro tip: Keep your naps under 20 minutes to avoid feeling groggy, and don’t nap after 3 p.m., or you may struggle to fall asleep at night.
8. Avoid Unnecessary Stimulation Throughout the Day.
Watching intense action and horror movies, stressful news programs, and even reading comments on divisive social media posts can ramp up adrenaline and cortisol production and activate your fight-or-flight stress response, which can exacerbate sleep and circadian rhythm disruptions. “Anything that stresses us stresses our cells and will have the potential to disrupt this cycle,” says Dr. Rawls. Try to avoid these in general, but particularly in the evening.
9. Minimize Light Exposure Two Hours Before Bed.
Your circadian body clock is most sensitive to light in the two hours before your typical bedtime — so this is when you want to start dimming the lights (use soft yellow lights in the evening versus harsh LEDs), turning off the TV, and putting away smartphones and laptops. Artificial light from screens emits large amounts of blue light, which contains particularly stimulating wavelengths known to suppress melatonin and elevate cortisol, which could block sleep. Of course, you may occasionally need to work late on your laptop or want to catch a movie with a friend, and in these situations, blue light-filtering glasses may help to a point, says Dr. Rawls.
10. Wind Down with Natural Sleep Aids.
Consider winding down with a caffeine-free herbal tea containing herbs like lemon balm, passionflower, bacopa, and motherwort, which gently curb tension and promote calm. Some of these herbs actually affect the same neurotransmitter receptors in the brain as prescription sleep aids, although much more mildly and safely, says Dr. Rawls. High-quality supplements containing these herbs and other calming compounds such as l-theanine, GABA, and low doses of melatonin (1 to 1.5 mg) may also be beneficial.
And — just in case you needed reminding — alcohol isn’t recommended when dealing with a chronic health condition, even as a last resort to snag some shut-eye. While it initially makes you sleepy, it becomes stimulating as it breaks down and can lead to frequent nighttime awakenings. It also alters the expression of genes that regulate circadian rhythms.
11. Keep Your Bedroom Calm, Cool, and Well Equipped.
To keep your body in wind-down mode at night, make your bedroom a sanctuary of calm. Start by clearing out the clutter, tech devices, or anything else that might cause you stress or unwanted stimulation. If you want to keep your phone near you, at the very least, turn on “do not disturb” mode (under your phone’s settings, you can allow notifications from specific individuals such as family members in case of emergencies).
Additionally, keep your bedside table stocked with any essentials you may need to troubleshoot symptoms that may flare at night — water, pain medication, a soothing muscle rub, a calming herbal tincture, etc. — so you don’t have to rummage around at 2 a.m. and work yourself up.
Finally, because a subtle drop in body temperature can also help trigger the onset of sleep, you may want to turn down the thermostat before you hit the sheets — the sweet spot appears to be 65 F, give or take a couple of degrees.
12. Be Strict about Your Bedtime and Wake Time.
To ensure your body’s cells have ample time to perform their vital repair processes, you should aim for at least eight hours of sleep per night, says Dr. Rawls. That said, getting this amount of shut-eye consistently is hard if your sleep schedule is all over the place. (Remember how we told you that routine and sameness are key?) The good news: By consistently going to bed and waking up at the same time — even on weekends — you can reinforce a healthy circadian rhythm and prime your body to fall asleep and wake up with relative ease. “A target bedtime of 10 to 11 p.m. and wakeup time of 6 to 7 a.m. is usually realistic for most people,” says Dr. Rawls.
Chronic health conditions — particularly poorly managed ones — often ramp up your fight-or-flight stress response, disrupting your circadian rhythm, preventing quality sleep, and robbing your body’s cells of vital maintenance and repair time. And poor lifestyle habits only add fuel to the fire. Fortunately, the simple hacks and habits above can help realign an out-of-whack circadian rhythm so that, over time, sleep comes much more easily, and your body has more of the resources it needs to heal from the cellular level on up.
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