Master Your Sleep Habits for Better Health
The impact of sleep quality on your health cannot be overstated. Research has linked poor sleep hygiene and sleep disturbances to an increased risk of developing numerous chronic conditions, from heart disease and obesity to psychiatric conditions, impaired cognition, autoimmune diseases, and digestive disorders [1, 2, 3, 4, 5, 6].
How well you sleep has a profound effect on how well your brain, gut, and immune system function. The inverse is also true: Imbalances in the gut or throughout the body can affect the quality of your sleep.
While most people have at least a general understanding of the importance of sleep, it also seems to be one of the first things that drops off when life gets in the way. For example, many of my patients are extremely diligent about following their diet and supplement protocols, but they don’t always hold their sleep hygiene to the same standard.
I mention this because I’ve also consistently found that by making sleep hygiene a priority rather than an afterthought, my patients achieve much better results with their health. The same has been true for my own health.
With all of that in mind, in this article, we will explore the impact of sleep on your health, the various elements of good sleep hygiene, causes and signs of poor sleep quality, and how to improve your sleep and your overall health.
The Impact of Poor Sleep Hygiene on Health
Sleep hygiene refers to the habits, practices, and environment that promote a good night’s sleep. Poor sleep hygiene may lead to sleep impairment, which has been associated with an increased risk of numerous conditions, including:
- Heart disease [1, 7]
- High blood pressure 
- Type 2 diabetes 
- Reduced cognitive function [4, 10]
- Irritable bowel syndrome (IBS) 
- Autoimmune disease 
- Obesity [2, 11]
- Metabolic syndrome 
- Psychological and mental health concerns 
- Impaired memory 
The conditions associated with improper sleep are broad, emphasizing its far-reaching impact. While you sleep, your body performs several different functions that are essential for the health of your gut, brain, and the rest of your body.
Sleep helps your brain recharge, removes toxic buildup and waste, and organizes and consolidates memories [13, 14]. Research shows that we need at least seven hours of sleep every night for appropriate cognitive function, learning, and behavior .
Sleep is also essential for metabolism regulation, detoxification, and immune system function [13, 15].
Key Elements of Sleep Hygiene
Good sleep hygiene takes into consideration not only the amount of sleep you get at night but also the timing and quality of sleep.
The key elements of sleep hygiene include:
- Duration of sleep
- Timing of sleep
- Quality and intensity of sleep
When it comes to sleep duration, the ideal length of time is an average of eight hours per night, with short durations (fewer than seven hours) and long durations (more than nine) both being linked to detrimental health effects [13, 16].
The timing of sleep also matters. A sleep schedule that is as consistent as possible is ideal, as this allows your circadian rhythm (your body’s internal clock) to normalize .
Finally, the quality of sleep is critical. You cycle through five stages of sleep at night: Rapid eye movement (REM) sleep, which is when dreaming occurs, and four stages of non-REM sleep, categorized by their depth.
Any sleep disruptions throughout the night can mean that you don’t spend enough time in each of these stages, which means that you may not be getting all of the benefits of a restful sleep .
Signs You’re Not Sleeping Well
If you regularly struggle to fall or stay asleep, this is an obvious indication that something is off. But what if you generally sleep through the night yet still wake up feeling tired or unrefreshed? This means that your sleep quality may not be where it should be.
Signs that your sleep quality is inadequate may include any of the following:
- You sleep for 7-9 hours but feel unrefreshed the next day.
- You’ve been told that you snore.
- You typically breathe through your mouth at night.
- Indicators include waking up very thirsty or with a dry mouth, drooling at night, and a history of cavities and/or periodontal disease.
- You have ongoing, unresolved symptoms, including chronic fatigue, brain fog, or gastrointestinal issues.
The good news is there are several different ways to improve your sleep quality naturally, which we’ll explore in detail below.
Causes of Poor Quality Sleep
Several different factors may contribute to sleep deprivation and poor sleep quality, most of which can be fairly easily resolved once they’ve been identified.
Causes of poor quality sleep may include:
- Improper sleep environment (i.e. too hot, too loud, or too bright)
- Exposure to blue light (from cell phones and other devices) and other bright lights at night 
- Irregular sleep schedule possibly caused by shift work [13, 18, 19]
- Stress, anxiety, and depression [13, 20]
- Gut microbiome imbalances and intestinal inflammation [21, 22]
- Improper breathing, mouth breathing, or an obstructed oral airway [23, 24, 25, 26, 27]
- Certain medications including corticosteroids, opioids, and antidepressants 
- Caffeine or alcohol consumption 
- Medical conditions including COPD, heart disease, fibromyalgia, and hyperthyroidism [13, 28]
- Sleep disorders including sleep apnea and insomnia 
- Hormonal imbalances 
The Gut-Sleep Connection
There are a few interesting connections between gut health and sleep quality.
The prevalence of sleep disorders and poor quality sleep is higher among patients with common gastrointestinal conditions, including IBS and IBD, than among healthy individuals [21, 30]. Poor sleep has also been linked to increased intestinal permeability (leaky gut) .
So do gut health imbalances lead to impaired sleep, or is it poor quality sleep that disrupts gut health? The answer is, most likely, both.
For example, one clinical trial found that low quality sleep led to lower levels of the “sleep hormone” melatonin, which were then associated with leaky gut .
Research has also shown that both leaky gut and gut inflammation are among the key factors leading to poor sleep quality among patients with IBD .
Probiotics have also been shown to help improve sleep [33, 34, 35, 36].
Healing your gut may help to resolve sleep issues, as it did in my case and as it has with many of my patients.
Your Step-by-Step Guide to Better Sleep Hygiene
The first step when it comes to improving poor sleep hygiene and your sleep quality is to make it a priority. Once you’ve made this commitment to yourself, there are several things that you can do to achieve your sleep goals and improve your overall health.
To set the stage for better sleep, focus on optimizing your schedule and your internal and external environments.
STEP 1: Optimize your internal environment.
- Follow a healthy, anti-inflammatory diet. Improving diet has been shown to be effective in treating sleep disorders including obstructive sleep apnea [37, 38]. A healthy diet will also help to improve other imbalances associated with impaired sleep, including inflammation, gut health, and hormonal balance. The Paleo diet is a good starting point.
- Avoid common sleep disruptors. Consuming caffeine and alcohol late in the day or in the evening can disrupt restful sleep and contribute to sleep disorders including insomnia .
- Get regular exercise. Getting regular exercise can help to improve your sleep quality and overall health [37, 38]. A systematic review of three meta-analyses found that regular exercise helped adults to sleep an average of 19% better overall . Exercise has also been shown to be helpful in the treatment of sleep apnea .
- Improve your gut health. Given the connections between sleep and the gut, healing your gut and reducing intestinal inflammation may help to improve your sleep quality.
- Take probiotics. Clinical trials have shown that taking probiotics can help improve sleep quality and reduce sleep disruptions for healthy individuals and those with depression, insomnia, and work-related stress [33, 34, 35, 36].
STEP 2: Optimize your external environment.
- Reduce blue light and bright light. Blue light, which we’re exposed to from screens like cell phones and tablets at night, has been shown to disrupt the sleep cycle, increase daytime sleepiness, and increase wakefulness at night. Research is also finding that any type of light exposure right before bed can be disruptive . To help normalize your sleep-wake cycle, make sure to get lots of natural light (sunlight) during the day, and reduce it at night. Sleep masks and/or blackout curtains can help to keep your environment dark at night. It’s also best to turn off all devices at least one hour before bedtime.
- Keep the temperature low. Cooler environmental and body temperatures have been associated with better sleep quality for most individuals. However, one clinical trial found that obstructive sleep apnea may worsen for some people in cooler temperatures . You may need to experiment with different temperatures to find your sweet spot.
- Strive for quiet. Noise in your environment may lead to distraction, annoyance, and disrupted sleep . If nighttime noise is unavoidable where you live, consider using earplugs.
STEP 3: Optimize your schedule for sleep.
- Set a regular sleep schedule. Plan for an optimal eight hours of sleep, and set your schedule accordingly. As much as possible, try to make your sleep schedule regular, meaning that you go to bed and wake up at the same time every day.
- Avoid strenuous exercise close to bedtime. While regular exercise is important for sleep and health, vigorous exercise less than an hour before bedtime might lead to reduced sleep time and efficiency .
- Avoid eating before bedtime. If possible, finish eating at least three hours before you plan to go to sleep for optimal digestion and healthy sleep.
- Wind down. Try to make sure that your bedtime routine is as calm as possible, favoring relaxing activities like reading or taking a warm bath and avoiding stressful activities like checking your email.
The Next Level of Sleep Optimization
Once you have the basics down, you may wish to take your sleep optimization even further with these techniques.
Take melatonin. Individuals who have trouble sleeping may not be producing or releasing enough of the sleep hormone melatonin. Melatonin is also available as a supplement. Several systematic reviews of clinical trials have shown that melatonin supplements can help to decrease the time it takes to fall asleep, improve sleep duration and quality, and regulate the sleep-wake cycle [44, 45, 46].
Track your sleep. Several devices can help to measure and track the quality of your sleep. The Oura Ring, one of the most popular devices, has been shown to detect sleep-wake cycles and sleep stages almost as well as clinical sleep study techniques . While a sleep tracking device itself may not directly improve your sleep, it’s a great way to develop an understanding of your sleep patterns and the factors that affect your sleep so that you can adjust your habits and lifestyle accordingly. For example, you may notice that the score on your Oura Ring goes down whenever you eat a certain type of food or drink alcohol before bed.
Another option to consider is an at-home sleep apnea test with a portable device like the WatchPAT. This technique is much easier and less invasive than clinical sleep studies, and can help you to identify sleep issues from the comfort of your home.
Improve your breathing and oral airway health. If you breathe through your mouth at night and/or if you snore, addressing this may be the key to improving your sleep quality, energy, cognition, and overall health.
Snoring is common, occurring in an estimated 32% of adults . But while it may sometimes be thought of as normal or just a nuisance, it’s actually an important sign of impaired breathing and sleep.
There are many simple breath training and myofunctional therapy exercises (physical therapy for the mouth) that can be incorporated into your routine in order to promote nasal breathing, an unobstructed oral airway, and a good night’s sleep.
A 2020 systematic review of nine clinical trials found that myofunctional therapy helped to improve sleep quality . Another systematic review found significant improvements in sleep apnea and snoring for both adults and children with myofunctional therapy .
Other techniques, including using wearable devices that help to reposition the jaw, mouth taping (in order to encourage nasal breathing), and even playing a wind instrument like the didgeridoo may be helpful for some people [26, 51, 52].
The Bottom Line About Poor Sleep Hygiene
Sleep hygiene is one of the most important pillars of health, and it’s crucial to make sure that it gets the attention it deserves within your wellness plan.
The sleep hygiene practices and techniques outlined here should help to improve sleep quality for most people.
If you’re still struggling with sleep problems after following this guide, there may be an underlying digestive, hormonal, or blood sugar imbalance that needs to be addressed.
Remember that the relationship between sleep and health goes both ways: Improving your sleep quality improves your overall well-being and vice versa.
My book, Healthy Gut, Healthy You, explains more about sleep and how it factors into your gut health and overall health protocol. For more individualized guidance and support, including to have an at-home sleep test done, you can request a consultation at my functional medicine center.
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