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Story at-a-glance

• According to a poll of 2,000 adults, the average time most people go to bed is before 10 p.m. — 9:54 p.m. to be exact
• Despite this reasonable bedtime, many still wake up feeling tired; this may be because your night’s rest is only restorative if you’re able to fall asleep and stay asleep
• Among adults, 4 in 10 say they’re bad sleepers, while another 60% say their nighttime routine needs work
• People with the most irregular sleep had the highest dementia risk and were 53% more likely to develop the condition than those with more regular sleep patterns
• The glymphatic system, which your brain uses for detoxification, is particularly active during sleep, which may actually serve to kickstart the system

Getting to bed too late is often blamed for feeling groggy the next morning. But according to a poll of 2,000 adults, the average time most people go to bed is before 10 p.m. — 9:54 p.m. to be exact.1

Despite this reasonable bedtime, many still wake up feeling tired. This may be because your night’s rest is only restorative if you’re able to fall asleep and stay asleep. It turns out, however, that regardless of bedtime, 4 in 10 say they’re bad sleepers, while another 60% say their nighttime routine needs work.

Further, only 24% said they sleep better when they go to bed earlier. A spokesperson for furniture retailer DFS, which commissioned the poll, explained, "Our study has shown how the actual time we go to bed can have a real impact on our sleeping routine as a whole. The hours of sleep we get is of course important, but the way we prepare ourselves and get ‘into the zone’ of sleep is also vital."2

This isn’t just a matter of waking up feeling energized, either. Proper sleep is essential to your physical and mental health, and if you skimp on it enough, a number of diseases can result.

Irregular Sleep Increases Dementia Risk by 53%

Going to bed and waking up around the same times each day is a key part of healthy sleep hygiene. It may also be important for protecting your health, according to research published in Neurology.3

"Sleep health recommendations often focus on getting the recommended amount of sleep, which is seven to nine hours a night, but there is less emphasis on maintaining regular sleep schedules," study author Matthew Paul Pase of Monash University in Melbourne, Australia said in a news release. "Our findings suggest the regularity of a person’s sleep is an important factor when considering a person’s risk of dementia."4

The study involved 88,094 participants with an average age of 62 years and looked into how sleeping patterns, specifically how regular they are, might be connected to the risk of developing dementia. Researchers tracked sleep patterns using a special method that measures if they were asleep or awake at the same times across several days.

Over about 7.2 years, 480 people developed dementia. It turned out that both very irregular sleep patterns and overly consistent sleep patterns (sleeping and waking up at exactly the same times every day) were linked to a higher risk of dementia compared to those with moderately regular sleep patterns. This relationship was U-shaped, meaning both extremes were associated with increased dementia risk.

Further, in a smaller group who had brain scans, those at the extremes of sleep regularity tended to have smaller amounts of brain gray matter and hippocampal (a part of the brain important for memory) volume. That said, people with the most irregular sleep had the highest dementia risk and were 53% more likely to develop the condition than those in the middle.5

Those with the most regular sleep, meanwhile, did not have a reduced dementia risk compared to the middle group, suggesting even moderate improvements in sleep regularity may benefit brain health.

"Effective sleep health education combined with behavioral therapies can improve irregular sleep patterns," Pase said. "Based on our findings, people with irregular sleep may only need to improve their sleep regularity to average levels, compared to very high levels, to prevent dementia. Future research is needed to confirm our findings."6

Sleep Jump-Starts Nightly Brain Detoxification

It’s worth nothing that your brain uses sleep as its time to flush out toxins and metabolic waste — compounds that could otherwise accumulate and contribute to neurodegenerative disease. Most of your body uses the lymphatic system for this purpose. As Forbes explains:7

"In short, a specialized 'sewerage' infrastructure called the lymphatic system. This is made up of various vessels and channels that, like our circulatory system, spread across the entire body. These vessels are filled with a fluid called lymph, which flows through tissues and organs, washing up and collecting debris as it goes.

Dirty lymph is eventually drained into the blood vessels, where it is carried to the kidneys and liver for final filtration and removal."

In your brain, however, it’s the glymphatic system that removes waste products, acting as a "brain-wide metabolite clearance system."8 By pumping cerebrospinal fluid through your brain's tissues, your glymphatic system flushes waste from your brain back into your circulatory system and liver for elimination.

It operates similarly to the lymphatic system in the rest of your body but is specialized for the unique environment of your brain and central nervous system. The term "glymphatic" combines "glial cells," which are cells in your brain that bring nutrients to neurons, and "lymphatic," reflecting its similarity to the body's lymphatic system.

The glymphatic system facilitates the removal of metabolic waste products from the central nervous system via a network that involves the perivascular space — the space surrounding blood vessels — cerebrospinal fluid and glial cells.

The glymphatic system is particularly active during sleep, which may actually serve to "kickstart" the system,9 highlighting the importance of a good night’s sleep for brain health. Scientists with Washington University School of Medicine in St. Louis10 also revealed that during sleep, neurons generate electrical signals that trigger rhythmic brain waves, propelling cerebrospinal fluid through the brain

These electrical waves may boost the function of the glymphatic system, helping cerebrospinal fluid penetrate deeper into the brain and pick up waste, enhancing the cleaning process.

Your Heart Also Needs Proper Sleep

Your heart, like your brain and overall health, needs at least seven, if not eight, hours of sleep to function optimally. In fact, getting enough sleep each night, and quality sleep at that, is associated with cardiovascular risk and research also found that sleep is connected with subclinical atherosclerosis,11 the early stages of hardening and narrowing of the arteries.

Researchers with the National Center for Cardiovascular Research in Madrid, Spain used coronary ultrasound and CT scans to measure the artery health of close to 4,000 middle-aged adults and analyzed it according to their sleep duration and quality.

Those who slept for less than six hours a night (very short sleep duration) were 27% more likely to have subclinical atherosclerosis than those who slept for seven or eight hours a night.

While atherosclerosis is often associated with heart disease, it can occur in any of your body’s arteries, with symptoms depending on which arteries are affected. Atherosclerosis in your brain can lead to stroke, for instance, while the condition in your kidneys can lead to high blood pressure or kidney failure, and atherosclerosis in the arteries in your arms and legs may lead to peripheral artery disease.

This implies, then, that proper sleep could play a major role in disease prevention via its role in preventing atherosclerosis alone. The effect is so significant that an accompanying editorial noted that, with additional trials to confirm, sleep could be placed "alongside diet and exercise as a key pillar of a healthy lifestyle."12

A Simple Way to Fall Asleep Faster

Anxiety and racing thoughts can make it difficult to fall asleep, even if you’re already in bed. When you become stressed, your breathing pattern and rate change naturally, but it’s important to be conscious of how triggers like this change your breathing habits — and what to do to resolve them.

The 4-7-8 breathing method, known for relaxation and promoting restful sleep,13 may help. Also known as "relaxing breath," the 4-7-8 breathing method involves a specific pattern of breath control developed by Dr. Andrew Weil, based on ancient yogic techniques, including pranayama.14

Using this breathing method before sleep may trigger a relaxation response in your body, shifting you from a state of heightened stress — sympathetic nervous system activation — to a state of calm, or parasympathetic nervous system activation. This transition helps reduce stress and anxiety, which are common culprits behind sleep disturbances.

Focusing on the breathing pattern also encourages mindfulness, which involves being present in the moment and can help quiet your mind. This focus can distract you from the day's stresses and worries that might interfere with sleep.

This specific pattern of breath control may also improve the balance of oxygen and carbon dioxide in your blood. Further, slowing down your breath can lead to deeper, more restful sleep by promoting physiological changes conducive to sleep, such as reduced heart rate and muscle relaxation.

It’s important to understand, however, that most breathing exercises, or techniques, aren’t a long-term solution because they don’t address the habits contributing to dysfunctional breathing in the first place. To get to the root of the problem and learn proper breathing, breathing behavior analysis learning techniques are typically necessary. If you’d like to try the 4-7-8 breathing method, however, it’s straightforward, as follows:

1. Prepare — Sit or lie down in a comfortable position. Close your eyes and take a moment to relax your body. Place the tip of your tongue against the tissue behind your upper front teeth and keep it there throughout the practice.

2. Inhale — Breathe in quietly through your nose for a count of 4 seconds.

3. Hold — Hold your breath for a count of 7 seconds.

4. Exhale — Exhale completely through your mouth, making a whoosh sound, for a count of 8 seconds.

This breathing cycle is repeated for four full breaths, but you can work your way up to eight repetitions over time.

How to Get a Good Night’s Rest

As mentioned, maintaining a regular bedtime and wake time is useful for brain health and overall sleep hygiene. But it’s just one piece of the puzzle to getting a good night’s sleep. I’ve compiled 50 top sleep tips you can use to fall asleep faster and stay asleep longer, which include sleeping in complete darkness.

Light (even that from a night light or alarm clock) can disrupt your internal clock and your production of melatonin, thereby interfering with your sleep. Also, keep the temperature in your bedroom cool, between 60 to 68 degrees F, and eliminate electromagnetic fields. Ideally, shut down the electricity to your bedroom by pulling your circuit breaker before bed and turning off your Wi-Fi at night.

Establishing a relaxing bedtime routine is also useful. This may include meditation, aromatherapy, essential oils, journaling or a massage from your partner. The key is to find something that makes you feel relaxed, then repeat it each night to help you release the tensions of the day and prepare for restful slumber.

Sources and References

• 1, 2 StudyFinds July 8, 2022
• 3 Neurology. 2024 Jan 23;102(2):e208029. doi: 10.1212/WNL.0000000000208029. Epub 2023 Dec 13
• 4, 5, 6 EurekAlert! December 13, 2023
• 7, 9 Forbes March 8, 2024
• 8 Scientific Reports February 2, 2018
• 10 Nature February 28, 2024
• 11 J Am Coll Cardiol. 2019 Jan 22;73(2):134-144
• 12 Journal of the American College of Cardiology January 2019, Volume 73, Issue 2
• 13 CNN September 16, 2022
• 14 Pocket January 3, 2022