When it comes to sleep, time is everything. The time you go to bed, the amount of time you sleep, the quality of the time you sleep, and the regularity of your bedtime and waking time all directly impact your physical, mental and emotional health and wellbeing, and even affect how long you live.
Disturbed sleep patterns are associated with a wide variety of health problems, from PTSD and cardiovascular and cerebrovascular disease to diabetes, depression, Alzheimer’s disease, obesity, high blood pressure, elevated blood sugar, chronic pain, gastrointestinal problems, neurological disorders, breathing problems, urinary tract issues and psychological concerns.1
The standard amount of sleep needed by the vast majority of adults is between seven to nine hours each night—the sleep length recommended by most doctors and health sites for the average adult. But we need sleep in varying degrees at different times of life. For example, infants, children and teens need more sleep than adults.
And sleep research is not an exact science. Yes, the apparent “optimum” amount of sleep is seven to nine hours, but there are studies that narrow that window. One such study conducted in Finland, which tracked 21,268 twins over the age of 18 from 1982 through 2003, found a “significantly increased risk of mortality” in both men and women who were “long sleepers,” sleeping more than eight hours a night.2
Long sleepers have also been found to be more susceptible to psychiatric diseases and to have a higher body mass index (BMI).3 “Short sleepers” who get less than seven hours sleep at night also have an increased risk of early death.2
Teens who sleep less than five hours or more than 10 hours a night have a higher rate of suicide than those who report a total sleep time of eight hours.4 Adults who regularly suffer from sleep disturbances and don’t get enough sleep also experience higher rates of suicide and suicidal thoughts.5
Suicide and suicidal thoughts have been linked to reduced production and transmission of the neurotransmitter serotonin in the brain, which is a side-effect of too little sleep.6 In general, people who experience restricted sleep are also more prone to anger.7
Irregular bedtimes and haphazard rising times negatively affect total sleep time at night and can wreak havoc on the body’s circadian rhythms, creating all sorts of physical, mental and emotional issues. Irregular sleep habits increase the risk for high cholesterol, hypertension, high blood sugar and obesity.
One recent study found that people who are typically inconsistent in their sleep and waking times had up to a 27 percent greater chance of developing metabolic issues compared to those who kept to a regular sleep schedule.8 Hyperactivity and behavioral problems have also been linked to irregular bedtimes, and children who manage to shift to a more regular bedtime experience notable improvement in these issues.9
Even something seemingly as insignificant as the time we go to bed is important. One recent study of over 100,000 people revealed that a sleep onset time between 10 p.m. and 11 p.m. was associated with the lowest incidence of CVD.10
Adolescents with a bedtime later than 11 p.m. have almost twice the risk of developing high blood pressure than young people who go to bed between 9 and 10 p.m.11 Students struggling to pass their classes in school have been found to go to bed later than their peers getting good marks. Furthermore, students who got less than 7 hours’ sleep on school nights reported more sleepiness during the day, depression and behavioral issues compared to those who slept more than 8 hours a night.12
The human sleep cycle is a relatively fragile thing that depends upon our individual circadian rhythm, maintained by the body’s internal “clock” located in the suprachiasmatic nucleus (SCN)—a tiny cluster of brain cells in the hypothalamus region of the brain. The SCN regulates biological functions such as appetite, hormone production and cell regeneration, and is itself regulated by cues from our environment, such as the fading of light in the evening and the rising of the sun at dawn.
Specific cells in the retina of the eye are designed to process light levels, informing our brain when night and day are coming. As light levels decrease, the hypothalamus produces GABA, a neurotransmitter that reduces brain activity.
The pineal gland, located right next to the hypothalamus, increases production of the hormone melatonin, which is the major sleep-inducing chemical in the body. Adenosine, another sleep-promoting molecule, is released from the nearby midbrain—unless you drink caffeine in the evening, in which case adenosine production can be disrupted. As bedtime approaches, body temperature begins to drop and continues to drop during the night as our metabolism decreases by about 15 percent.
Throughout our 24-hour day/night cycle, the SCN regulates all sorts of other body functions, stimulating the digestive system to produce proteins related to appetite and telling the endocrine system when to release hormones. At a cellular level, the circadian clock regulates our gene expression, guiding a whole host of body functions such as brain metabolism and stem cell proliferation through transcription (converting DNA sequences to RNA) and translation (converting those RNA sequences into sequences of amino acids during protein synthesis).
It doesn’t take much for this clock to be disrupted, as anyone who has flown across time zones and awakened jetlagged the next morning knows only too well. Long term, an out-of-whack circadian clock contributes to aging and cognitive decline.1 Disrupted circadian rhythms can also signal the development of neurodegenerative diseases such as Alzheimer’s and Parkinson’s, as well as metabolic diseases and cancers.2
All your body rhythms are synchronized by a daily circadian rhythm, which is regulated by exposure to sunlight. Too little natural light exposure and too much artificial light exposure can both negatively impact serotonin levels and melatonin production, which in turn affect your ability to sleep well at night
Women are more prone to experience frequent bouts of sleeplessness than men, often several times per week. And they do so especially from age 45 onward.
Perimenopause and menopause cause hormonal changes that are associated with increased sleep-onset times, meaning it takes longer to get to sleep.13 Post-menopausal women may develop sleep disorders including insomnia, obstructive sleep apnea (when muscle relaxation in the throat temporarily blocks the airway) and restless legs syndrome, all of which contribute to irregular sleep patterns.14
All over the world, doctors, nurses and other healthcare workers are considered a high-risk group for suicide.15 Aside from stress, this may well be the result of their highly irregular sleep/wake schedules and shortened sleep cycles.
Shift workers are notoriously susceptible to sleep disorders and shortened sleep cycles due to disruption of their circadian rhythms. Sleep and circadian rhythm disruption increases the risk of cardiovascular problems, cognitive impairment, metabolic syndrome, inflammation and psychiatric issues including depression.16 Sleep and circadian rhythm disruption may even be linked to the development of certain types of cancer.17
Long working hours—55 hours a week and more—are strongly associated with reduced sleep duration.18 Not surprisingly, long working hours have also been associated with many of the health conditions linked to poor sleep habits and interrupted sleep patterns, including cardiovascular diseases, chronic fatigue, depression, anxiety and injuries.19
Last but not least is the age factor. Many older adults—women and men alike—are affected by sleep disorders including insomnia, sleep apnea and restless legs syndrome, all of which create irregular sleep patterns contributing to health issues.
Older adults also tend to experience a circadian shift to something called a morning chronotype. They may have been life-long night owls, and suddenly they start waking early in the morning and getting sleepy earlier at night.
Young people frequently experience the exact opposite. As hormone production kicks into gear during puberty, adolescents shift into what’s called an evening chronotype, which means they tend to want to stay up late and sleep late in the morning. This is why an estimated 69 percent of teenagers are considered to be sleep deprived. Their body’s circadian rhythm is out of sync with their social environment, where school starts early in the morning.
And then there’s the rest of us. No matter our sex, age or occupation, about one-third of adults just don’t get enough sleep at night. With stress over the pandemic triggering increasing amounts of insomnia, this figure has skyrocketed in the past two years.
“It’s a big deal during the pandemic because we have this master clock in our brain which is reset every day by light,” says Heather Darwell-Smith, a psychotherapist at the London Sleep Center. “The light/dark cycle is how the body tracks. Of course, what’s happened these past two years is that people are getting up later. They’re not going outside; they’re just in their houses on their screens all day. They might go for a walk, but they’re just not getting enough light photons to the brain to be able to reset their clock every day.”
Cognitive behavioral therapy
Heather Darwell-Smith of the London Sleep Center says her basic approach to helping clients get a good night’s sleep is cognitive behavioral therapy for insomnia (CBT-I), which works with and conditions the nervous system. “If you’re in hyperarousal and stressed, it’s entirely logical that you won’t sleep because the stress response calls the body to be alert, triggering the hypothalamus to send the message to flood the system with adrenaline and cortisol, preparing the body for fight, flight, freeze or whatever else it needs to do.”
She walks clients through a whole-life examination to identify stressors and habits that may have upset their circadian rhythms, examining—and challenging—anxiety and any negative thoughts, feelings and unrealistic expectations around sleep. She also employs behavioral modification using relaxation training such as meditation, sleep restriction and stimulus control.
Her recommendations involve the following:
Set a regular morning rise time to strengthen your body’s ability to regulate sleep and wakefulness. Ideally, you should do the same for bedtime. As you follow a regular rising time, you overcome bad habits and sleep disorders like insomnia and strengthen your body’s circadian rhythm.
Go to bed only when sleepy. Although it flies in the face of an optimum bedtime between 10 p.m. and 11 p.m., doing this increases the chances that you will fall asleep quickly and not get into bad habits that can build up to insomnia. It’s better to follow your body’s natural rhythms and fall asleep easily than try to force sleep. It just doesn’t work.
If you can’t fall asleep within 20 minutes, get up and return when sleepy. If you stay wakeful and agitated in bed, this just reinforces the body’s association between bed and wakefulness instead of bed and sleep.
Smartphone applications such as CBT-I Coach are available for patients undergoing CBT-I with a healthcare professional as an additional support. Combining CBT-I therapy with mindfulness-based stress reduction is sometimes called mindfulness-based therapy for insomnia (MBTI).1
Sleep Hub ®. Playing certain sounds can influence the brain to follow certain brain states and patterns that mimic what happens in a normal sleep cycle.
“If people are not in a normal sleep cycle and it’s all gotten deranged because of bad habits, then you can encourage the right pattern by retraining,” says Dr Chris Dickson. “The device emits a fairly low frequency with beats and pulses of various frequencies, which play quietly in the background and are masked by nature sounds.
“It doesn’t work if you listen to it. It works by not really listening to it, so the sound becomes uninteresting at a subconscious level. Then those sounds can influence brain rhythms.”
Dickson says that in an in-house study, 92 percent of the people using the device experienced an average of two hours and 35 minutes of extra sleep per night. It also reduced nighttime waking by 50 percent.
White noise. The use of a white noise machine has been shown to help dampen environmental noises and improves sleep quality.1
Avoid blue light stimulation. Using electronic devices before bedtime and even excessively during the day causes long sleep onset latency and short sleep duration in adolescents. Light suppresses melatonin production, especially the short-wavelength (blue) portion of the spectrum between 446 and 477 nanometers.1
For a good night’s sleep, it is best to reduce exposure to devices that emit these light frequencies.
Wear amber lenses for two hours preceding bedtime. This resolves the blue light issue from watching TV and being on electronic devices.2
Reduce overall screen time. The amount of screen time is directly related to insomnia and shorter sleep in young people.3
Avoid daytime napping.
Avoid alcohol, nicotine and caffeine before bedtime.
Set the stage. Invest in low lighting, eliminate all electronic equipment in the bedroom, reduce clutter, buy a comfortable mattress and attractive bedding, invest in black-out curtains, paint your room a soothing shade of blue or green in a matte finish, and keep the room between 60–67°F (16–19°C).
Sleep naked. Your body will stay cooler at night, and you’ll sleep better.
Consider sleeping alone. Many partners don’t like the same kind of mattress or sleep conditions as their mate. Struggling to sleep under unfavorable conditions or with a snoring partner increases stress and fatigue and reduces your own sleep quality. When all else fails, snuggle, then go to your own rooms!
Romance. Sexual activity has been linked to improved sleep quality.1
The full significance of sleep in our lives is not completely understood. Poor sleep patterns are associated with poor health, but it’s not a clear-cut, direct cause-and-effect relationship. We don’t yet know the physiological “whys.” It is speculated that reduced sleep could trigger an autonomic nervous system imbalance.
And the presence of increased levels of pro-inflammatory cytokines (proteins involved in cell signaling) that accompanies sleep loss in turn dysregulates immune function, leading to low-grade inflammation.20 But much more study is needed in this area to determine the precise mechanisms involved.
In the meantime, everybody’s best bet is pretty simple: Get to bed every night between 10 and 11 p.m., sleep for eight hours, and get up at six or seven every morning. And no, you can’t make up for lost sleep on the weekends.
The belief that sleep deprivation can be compensated for by sleeping late on weekends or other vacation days is a myth.21 In fact, such sleep irregularity may end up disrupting circadian rhythms even more, ensuring more sleep-deprived nights than otherwise. And although a lot of people like to brag about how they can get by on only four or five hours of sleep a night, this, too, is a myth for the most part.
Although some famous short-sleepers like Leonardo da Vinci and Margaret Thatcher could manage well on four to six hours a night, they are a small minority. Only about one percent of the population is genetically wired for such a short sleep duration.
Relying on pharmaceutical sleep aids to help regulate sleep patterns doesn’t work either. Sleep is a highly active and constantly changing state. During eight hours of sleep, we experience between four and six sleep cycles consisting of roughly four main stages: non-REM 1, non-REM 2, non-REM 3 and REM (characterized by rapid eye movement).
Our most vivid dreams occur during REM sleep and are thought to be related to emotional processing of events during the day. During REM sleep, our breathing and heart rate reach almost waking levels, and our arms and legs experience a state of near-paralysis. Meanwhile, brain areas involved in emotion and sensory processing become highly active.22
“Sleep cycles are very active processes, and sleep is not sorted by pharmaceuticals,” says Dr Chris Dickson, Executive Director of Cambridge Sleep Sciences in Milton, UK.
“When you understand that, it’s not surprising that taking a drug—which builds up to a steady-state level and then declines—is not the best way to manage sleep. How can a drug manage a rapidly shifting brain state which is changing every 20 minutes? It doesn’t make any sense.”
Darwell-Smith agrees that pharmaceuticals are not the answer to a good night’s sleep. On top of that, she points out that many common medications people take for other conditions negatively affect sleep quality and reduce the duration and quality of REM sleep.
“And if you don’t have enough REM sleep, you’re more prone to be more highly emotional and even catastrophize issues,” she says. “Especially today, with the pandemic situation, if you are on medications you have to think about how to maximize the quality of your sleep.”
Magnesium. This mineral improves sleep efficiency, sleep time and sleep onset latency in elderly people.
Suggested daily dosage: 200 mg 30 minutes before bedtime
Melatonin. A hormone, it helps reduce long sleep onset and regulates sleep-wake patterns.1
Suggested daily dosage: There is no official recommended dose, but for adults, a range of 0.5 mg to 5 mg taken an hour before bedtime is safe and effective (melatonin is a prescription-only medicine in the UK)
Chamomile. A traditional go-to, the use of chamomile, usually in tea form, has been shown to improve sleep quality among the elderly. But it’s not a bad idea for anyone suffering from sleep disorders.2
Valerian. Studies show that valerian improves sleep quality without side-effects.3
Suggested daily dosage: Within an hour of turning in for the night, take 30–40 drops of valerian tincture in a glass of water
Passionflower. Especially helpful for restlessness and people who have trouble staying asleep during the night.
Suggested daily dosage:Take as a tea near bedtime, or as 40–60 drops of a tincture in a glass of water three times daily between meals4
Warm milk and honey. Yes, grandma was right about drinking warm milk before bedtime. A study of patients in a hospital’s heart unit found that drinking warm milk and honey for three days contributed to noticeable sleep improvement.5 Sleep promotion is likely due to the amino acid tryptophan found in milk.
Fermented milk. One study showed that the probiotic Lactobacillus helveticus found in fermented milk improves sleep in elderly people.6
Main article
|
References |
|
|
1 |
Circulation, 2019; 139(21): 2483–4; Neuropsychiatr Dis Treat, 2021; 17: 2549–66 |
|
2 |
Sleep, 2007; 30(10): 1245–53 |
|
3 |
PLoS One, 2014; 9(9): e106950 |
|
4 |
J Clin Sleep Med, 2011; 7(4): 351–6 |
|
5 |
Neuropsychiatr Dis Treat, 2007; 3(6): 735–43 |
|
6 |
Sleep, 2005; 28(12): 1505–10 |
|
7 |
Exp Psychol Gen, 2019; 148(7): 1239–50 |
|
8 |
Diabetes Care, 2019; 42(8): 1422–9 |
|
9 |
Pediatrics, 2013; 132(5): e1184–93 |
|
10 |
Eur Heart J Digit Health, 2021; 2(4): 658–66 |
|
11 |
Am J Hypertens, 2020; 33(3): 269–77 |
|
12 |
Child Dev, 1998; 69(4): 875–87 |
|
13 |
Menopause, 2020; 27(3): 295–304 |
|
14 |
J Sleep Disord Ther, 2015; 4(5): 212 |
|
15 |
PLoS One, 2019; 14(12): e0226361 |
|
16 |
Occup Med (Lond), 2010; 60(1): 10–20 |
|
17 |
Chronobiol Int, 2016; 33(4): 325–50 |
|
18 |
Am J Epidemiol, 2009; 169(5): 596–605 |
|
19 |
Int J Environ Res Public Health, 2019; 16(12): 2102 |
|
20 |
Int J Environ Res Public Health, 2021; 18(24): 13158 |
|
21 |
Curr Biol, 2019; 29(6): 957–67.e4 |
|
22 |
US National Institute of Neurological Disorders and Stroke, “Brain Basics: Understanding Sleep.” www.ninds.nih.gov |
Circadian rhythms
|
References |
|
|
1 |
Nat Rev Neurosci, 2012; 13(5): 325–35 |
|
2 |
J Clin Invest, 2017; 127(2): 437–46 |
Maximize your sleep quality
|
References |
|
|
1 |
Neuropsychiatr Dis Treat, 2021; 17: 2549–66 |
Sleep aid devices
|
References |
|
|
1 |
J Caring Sci. 2016 Jun; 5(2): 103–9 |
Develop good sleep habits
|
References |
|
|
1 |
J Appl Physiol (1985), 2011; 110(3): 619–26 |
|
2 |
J Psychiatr Res, 2018; 96: 196–202 |
|
3 |
Sleep Med, 2019; 57: 51–60 |
Create a good sleep atmosphere
|
References |
|
|
1 |
Menopause, 2021; 28(6): 619–25 |
Supplements that help you sleep well
|
References |
|
|
1 |
Sleep Med Rev, 2017; 34: 10–22 |
|
2 |
Complement Ther Med, 2017; 35: 109–14 |
|
3 |
Am J Med, 2006; 119(12): 1005–12 |
|
4 |
Phytother Res, 2011; 25(8): 1153–9 |
|
5 |
Clin Nutr ESPEN, 2018; 28: 132–5 |
|
6 |
Eur J Clin Nutr, 2009; 63(1): 100–5 |
