People who wake up during the night to urinate shouldn't automatically blame a urological problem. Sleep apnea, a breathing-related sleep disorder, could be the cause.
A new study suggests that night time urination, or nocturia, is comparable to loud snoring as a marker for obstructive sleep apnea, a disorder in which soft tissue in the throat blocks the flow of air into the lungs, disrupting sleep.
Previous studies established a link between nocturia and sleep apnea, a potentially serious condition that affects about 25 percent of U.S. men and 10 percent of U.S. women, the researchers said. But they believe this is among the first to show that screening for nocturia could help doctors identify patients with apnea.
The study also suggests that a common treatment for sleep apnea -- positive airway pressure (PAP) therapy -- can reduce symptoms of nocturia, thereby improving sleep and preventing debilitating falls among elderly people who get out of bed at night to use the bathroom. PAP involves wearing a pressurized air mask while sleeping.
Typically, doctors screen for apnea by assessing patients' weight (the condition is associated with overweight/obesity) and asking if they snore heavily, notice breathing problems at night or feel tired during the day (because of interrupted sleep). But because many patients, especially those who sleep alone, are unaware that they snore, apnea often goes undiagnosed.
"When you ask people about symptoms like snoring and gasping, they tend to say, 'No, I don't have them'," said study author Edward Romero, research coordinator at the Sleep & Human Health Institute in Albuquerque, N.M. "But it's very easy for them to realize that they wake up at night to go to the bathroom."
One of Romero's co-authors, institute director Dr. Barry Krakow, said doctors and patients are quick to blame nocturia on diabetes, prostate enlargement and other medical conditions with which it is associated. "I see patients all the time who think they're waking up to urinate because they have prostate trouble or a small bladder," Krakow said. "About 80 percent of the time we discover that apnea is the cause of their problem."
Besides nocturia and snoring, symptoms of sleep apnea include daytime drowsiness, memory problems and depression. Untreated sleep apnea can lead to high blood pressure, blood clots and heart disease.
For the study the researchers reviewed data on 1,007 adults treated at two sleep clinics in New Mexico between 2005 and 2007. Of the participants, 797 were diagnosed with sleep apnea, 777 reported snoring and 839 reported nocturia. Neither snoring nor nocturia was proof of apnea, but the two symptoms were similar in their power to predict it. Snoring was reported by 82.6 percent of apnea sufferers, and 84.8 percent of apnea sufferers reported nocturia.
The authors propose further research be conducted to confirm the effectiveness of nocturia as an apnea screening tool.
Mary Umlauf, a professor at the University of Alabama Capstone College of Nursing in Tuscaloosa and a noted nocturia researcher, said the study could play an important role in dispelling "old wives' tales" about nocturia.
"Many health-care providers and ordinary people think of nocturia as a urological or gynecological problem," she said. "They don't understand that sleep apnea can cause the body to produce too much urine at night.
"People who wake up to urinate shouldn't assume that it's my prostate, or 'I'm just old'," she said.
Updated November 2nd 2017
Erratic and disruptive behaviour at work can be caused by even a single night's loss of sleep, say researchers.
Lack of sleep does not only mean tired workers, says the study, but can also cause "unwanted" activity, which it links to lower levels of self-control.
The study, published by the Rotterdam School of Management, says that such sleep-related disruption can cost billions in lost productivity.
Sleeplessness can cause a "destructive cycle" in work, says the study.
"Unwanted behaviour in the workplace often stems from selfish impulses that are not kept in check by self-control," says researcher Laura Giurge of the Rotterdam School of Management, Erasmus University in the Netherlands.
This could be anything from being rude to someone else in the office or increasing the likelihood of workplace theft.
But the study suggests that lack of sleep, even for a single night, can be a powerful influence over people who would otherwise not behave that way.
"This study shows that the display of unwanted behaviour is not a fixed character trait," says Ms Giurge.
"It can vary from day to day, even within the same person."
The study argues that lack of sleep can reduce people's sense of self-control and their ability to "regulate their impulses" - so that they behave in a way that they would not do normally.
"This can lead into a possibly destructive cycle," says the study and could contribute to unethical behaviour.
Such lack of sleep can also make it more difficult for people at work to overcome feelings of failure, says the study, with workplace problems seeming to become overwhelming.
There have been previous studies, which have examined how sleep deprivation can disrupt "moral judgement" and alter the quality of decision-making.
This has been studied in areas such as whether lack of sleep changes the behaviour of judges and how sleep deprivation might change how soldiers behave under pressure.
Sean Coughlan
Updated October 29th 2017
Studies carried out around the world, looking at how often diseases occur in different groups of people across a population have come to the same conclusion: both short sleepers and long sleepers are more likely to have a range of diseases, and to live shorter lives. But it's hard to tell whether it is short sleep that is causing disease or whether it is a symptom of a less healthy lifestyle. Short sleepers are generally defined as those who regularly get less than six hours' sleep and long sleepers generally more than nine or 10 hours' a night.
Pre-puberty, children are recommended to get as much as 11 hours' sleep a night, however, and up to 18 hours a day for newborn babies. Teenagers should sleep for up to 10 hours a night. Shane O'Mara, professor of experimental brain research at Trinity College Dublin, says that, while it's difficult to tell whether poor sleep is a cause or a symptom of poor health, these relationships feed off each other.
For example, people who are less fit exercise less, which leads people to sleep badly, become exhausted and less likely to exercise, and so on. We do know that chronic sleep deprivation - that is, under-sleeping by an hour or two a night over a period of time - has been linked time and again by scientists to poor health outcomes: you don't have to go for days without sleep to suffer these negative effects.
What happens in your body when you don't sleep enough?
Poor sleep has been linked to a whole range of disorders. A review of 153 studies with a total of more than five million participants found short sleep was significantly associated with diabetes, high blood pressure, cardiovascular disease, coronary heart disease and obesity.
Studies have shown that depriving people of enough sleep for only a few nights in a row can be enough to put healthy adults into a pre-diabetic state. These moderate levels of sleep deprivation damaged their bodies' ability to control blood glucose levels. Vaccines are less effective when we are sleep deprived, and sleep deprivation suppresses our immune system making us more prone to infection. One study found participants who had fewer than seven hours of sleep were almost three times more likely to develop a cold than those who slept for seven hours or more.
People who don't sleep enough also appear to produce too much of the hormone ghrelin, associated with feeling hungry, and not enough of the hormone leptin, associated with feeling full, which may contribute to their risk of obesity. There are also links to brain function and even in the long term to dementia.
Prof O'Mara explains that toxic debris builds up in your brain during the course of the day and waste is drained from the body during sleep. If you don't sleep enough, you end up in a mildly concussed state, he says. The impact of sleeping too much is less understood, but we do know it is linked to poorer health including a higher risk of cognitive decline in older adults.
We need different types of sleep to repair ourselves.
After we fall asleep we go through cycles of sleep stages, each cycle lasting between 60 and 100 minutes. Each stage plays a different role in the many processes that happen in our body during sleep.
The first stage in each cycle is a drowsy, relaxed state between being awake and sleeping - breathing slows, muscles relax, the heart rate drops.
The second stage is a slightly deeper sleep - you may feel awake and this means that, on many nights, you may be asleep and not know it.
Stage three is deep sleep. It is very hard to wake up during this period because it is when there is the lowest amount of activity in your body. Stages two and three together are known as slow wave sleep, which is usually dreamless.
After deep sleep we go back to stage two for a few minutes, and then enter dream sleep, also called REM (rapid eye movement). As the name suggests, this is when dreaming happens. In a full sleep cycle a person goes through all the stages of sleep from one to three, then back down to two briefly, before entering REM sleep.
Later cycles have longer periods of REM, so cutting sleep short has a disproportionately large effect on REM.
Shift workers who have disturbed sleep get sick more often and have been associated with a host of health problems. Researchers have found shift workers who get too little sleep at the wrong time of day may be increasing their risk of diabetes and obesity.
Shift workers are significantly more likely to report "fair or bad" general health according to a 2013 NHS study, which also found people in this group were a lot more likely to have a "limiting longstanding illness" than those who don't work shifts. People who work shifts are significantly more likely to take time off sick, according to figures from the Office for National Statistics.
There is a far bigger gap for non-manual workers than manual workers - lack of sleep seems to have a bigger impact on those doing more sedentary jobs and many of us are feeling more sleep deprived than ever. A big piece of research looking at data from 15 countries found a very mixed picture. Six showed decreased sleep duration, seven increased sleep duration and two countries had mixed results. Lots of evidence suggests the amount we sleep hasn't changed that much in recent generations. But if you ask people how sleep deprived they think they are, a different picture emerges.
So why do so many people report feeling tired?
It may be that this problem is concentrated in certain groups, making the trend harder to pick up on a population-wide level. Sleep problems vary considerably by age and gender, according to one study of 2,000 British adults. It found women at almost every age have more difficulty getting enough sleep than men.
The sexes are more or less level at adolescence but women begin to feel significantly more sleep deprived than men during the years where they may have young children, while work may become more demanding. The gap then shrinks again later in life.
Caffeine and alcohol both affect sleep duration and quality and later nights and more social activities mean some of us are getting less rest, despite having the same number of hours of sleep, according to Prof Derk-Jan Dijk, of the University of Surrey's sleep research centre.
Some people may also sleep too little during the week and catch up at the weekend, bringing the average up but leaving those people feeling sleep deprived.
For example, adolescents are particularly at risk of becoming sleep deprived, according to Prof Dijk. Aside from a few outliers - Margaret Thatcher could apparently get by on only four hours a night - people tend to go to bed in the late evening for around seven or eight hours.
But this wasn't necessarily always the norm according to Roger Ekirch, a history professor at Virginia Tech in the USA. He published a paper in 2001 drawn from 16 years of research.
His subsequent book, At Day's Close, contained a wealth of historical evidence suggesting that hundreds of years ago, humans in many parts of the world slept in two distinct chunks.
Dr Ekirch uncovered more than 2,000 pieces of evidence in diaries, court records and literature which suggest people used to have a first sleep beginning shortly after dusk, followed by a waking period of a couple of hours, then a second sleep. He thinks this means the body has a natural preference for segmented sleep.
Not all scientists agree. Other researchers have found hunter-gatherer communities in the modern world who sleep in one block despite not having electric lighting. This suggests sleeping in two blocks is not necessarily our default.
According to Dr Ekirch the shift from biphasal to monophasal sleep happened in the 19th Century because domestic lighting pushed bedtimes later with no corresponding change in rising time, improved lighting changed the human body clock, and the industrial revolution put a greater emphasis on productivity and efficiency.
Sleep experts say teenagers need up to 10 hours sleep a night, but almost half don't get this much according to the NHS.
Bedrooms are supposed to be a place of rest but are increasingly filled with distractions like laptops and mobile phones, making it harder for young people to nod off. We have more different types of entertainment on offer than ever, making the temptation to stay awake greater. The blue light emitted by electronic devices makes us feel less sleepy. And the activity itself, be it talking to friends or watching TV, stimulates our brain when it should be winding down.
Digital Awareness UK and the Headmasters and Headmistresses Conference recommend a nightly "digital detox", putting mobile devices away for 90 minutes before lights out. Last year the two organisations commissioned a poll which, found a high proportion of young people check their phones after going to bed.
More people are turning up at their doctors complaining of problems sleeping. Analysing data collected by NHS England, the BBC found in June that the number of sleeping disorder tests had increased every year over the past decade. There are a number of factors, but the biggest is probably the rise in obesity, according to Dr Guy Leschziner, a consultant neurologist at Guy's and St Thomas' Hospital's Sleep Disorders Centre.
The most common and fastest-growing complaint he sees is obstructive sleep apnoea - where the airway collapses and people stop breathing in their sleep - and this is strongly related to weight. The media has also played a role because people are more likely to go to their GPs having read an article or searched for their symptoms online, he says.
The recommended treatment for insomnia is cognitive behavioural therapy, and doctors are increasingly aware that they shouldn't be prescribing sleeping pills. But many still do because it's difficult to access non-drug based treatments, particularly outside big cities.
Body Clock: What makes you tick?
One study looked at sleep habits in 20 industrialised countries.
It found variations of up to an hour in the time people went to bed and woke up, but overall sleep duration was fairly constant across countries. Generally, if a population on average went to bed later, they woke up later too, although not in every case.
Researchers have concluded that social influences - hours worked, timing of school, leisure habits - play a far bigger role than the natural cycle of light and dark. In Norway, where the period of lightness each day varies through the year from zero to 24 hours, sleep duration throughout the year only varies on average by about half an hour.
Both in countries like the UK, where dusk and dawn times vary considerably across the seasons, and in countries closer to the Equator where dusk and dawn times vary minimally, sleep duration remains constant through the year.
But what about the impact of artificial light?
A study of three communities who had no access to electricity, in Tanzania, Namibia and Bolivia, found the average sleep duration was 7.7 hours - in step with industrialised countries. So sleep duration seems remarkably consistent throughout the world - it's the time we all go to bed and wake up that varies slightly.
These pre-industrialised communities did not fall asleep as soon as it got dark, but around three hours after sunset and generally woke before sunrise. Most studies in this area suggest that artificial light delays sleep time but does not necessarily decrease overall sleep duration. There have always been morning people and evening people. We even have genetic evidence that backs this up. But the introduction of artificial light appears to have exacerbated this effect, particularly for people who prefer to stay up late.
If you are already inclined towards being a night owl, artificial light will make you stay up even later. About 30% of us tend towards being morning people and 30% towards being evening people, with the other 40% of us somewhere in the middle - although marginally more people prefer early rising to late nights.
We do have some control over our body clocks, however. Those who are naturally late to bed and late to rise can try reducing their exposure to light in the evenings and making sure they get more light exposure in the daytime.
A team of researchers took a group of volunteers camping in Colorado, where they had no access to artificial light. Only 48 hours was enough to shift the campers' body clocks forward by almost two hours.
Levels of melatonin, the hormone that tells our body to prepare for sleep, began rising earlier in the volunteers - their bodies were preparing for sleep much closer to sunset.
By Rachel Schraer & Joey D'Urso
Updated October 29th 2017
A child will struggle with reading if their mother snores through pregnancy, new research reveals.
A decade-long study by the University of Sydney shows children born to mothers affected by sleep apnoea during pregnancy tended to score lower in reading tests.
More than 209 babies born in New South Wales to mothers with the sleep disorder between 2002 and 2012 were tracked through the first nine years including standardised educational test scores in their third year of school.
The results were compared with the other 626,000 children born in the state across the decade whose mothers did not snore.
While results of the longitudinal study, released this week at the annual Australasian Sleep Association conference in Auckland, showed the condition was associated with low reading test scores it was not linked to childhood death, developmental vulnerability, special needs or low numeracy test scores.
But researchers did find children of snoring mothers were more likely than other children to need additional hospital treatment in their first six years.
"Our study shows without a doubt that maternal sleep apnoea during pregnancy is associated with poorer childhood health," said lead researcher Yu Sun Bin.
The first step in addressing the problem was to identify sleep apnoea in pregnant women.
Better diagnosis and treatment of pregnant women with obstructive sleep apnoea could help protect their children from health problems in the early years of life, said Bin.
There was also a possibility the maternal apnoea put a child's intellectual ability at risk but this would need further study.
"Until more studies done, mothers with sleep apnoea should be reassured that their kids are not worse off," Bin said.
The next step was to have a large scale systematic screening of all mothers for sleep apnoea to gauge the extent of the problem.
At this stage they did not know why the reading ability was affected.
She said researchers had been left "very confused" by the reading result and said it needed further exploration in future studies.
Bin said the groundbreaking study had thrown up many questions regarding sleep apnoea and pregnancy including whether it was triggered by the growing womb.
If a mother was pregnant and knew she suffered from the sleep disorder Bin advised her to seek medical advice.
"It's important not to worry. Speak to your obstetrician and see what treatment options are there for you."
Sleep specialist Dr Stuart Jones called the findings "fascinating".
It was fairly common knowledge the sleeping disorder wasn't good news for the health of pregnant women, he said, but it was surprising the issue affected the cognitive development of their child.
The Counties Manukau District Health Board doctor recommended maintaining a healthy weight and being mindful of sleeping positions as ways to combat sleep apnoea.
"Research showed that people are more likely to snore if they're on their back rather than on their side," he said.
Jones said the results linked into the results of other studies, which highlighted a link between habitual snoring throughout childhood and poor academic performances.
Updated October 27th 2017
Many people think they can teach themselves to need less sleep, but they’re wrong, said Dr. Sigrid Veasey, a professor at the Center for Sleep and Circadian Neurobiology at the University of Pennsylvania’s Perelman School of Medicine.
We might feel that we’re getting by fine on less sleep, but we’re deluding ourselves, Dr. Veasey said, largely because lack of sleep skews our self-awareness. “The more you deprive yourself of sleep over long periods of time, the less accurate you are at judging your own sleep perception,” she said.
Multiple studies have shown that people don’t functionally adapt to less sleep than their bodies need. There is a range of normal sleep times, with most healthy adults naturally needing seven to nine hours of sleep per night, according to the National Sleep Foundation. Those over 65 need about seven to eight hours, on average, while teenagers need eight to 10 hours, and school-age children nine to 11 hours. People’s performance continues to be poor while they are sleep deprived, Dr. Veasey said.
Extended vacations are the best times to assess how much sleep you truly need. Once you catch up on lost sleep and are not sleep deprived, the amount you end up sleeping is a good measure how much you need every night.
You can ask yourself the questions, “Do you feel that your brain is much sharper, your temper is better, you’re paying attention more effectively? If those answers are yes, than definitely get the sleep,” said Dr. Veasey, who realized -- to her chagrin -- that she needs nine hours of sleep a night to function effectively.
Health issues like pain, sleep apnea or autoimmune disease can increase people's need for sleep, said Andrea Meredith, a neuroscientist at the University of Maryland School of Medicine.
A misalignment of the clock that governs our sleep-wake cycle can also drive up the need for sleep, Dr. Meredith said. The brain’s clock can get misaligned by being stimulated at the wrong time of day, she said, such as from caffeine in the afternoon or evening, digital screen use too close to bedtime, or even exercise at a time of day when the body wants to be winding down.
Updated October 24th 2017
An estimated 60% of us share a bed with someone else. It’s considered as being totally normal. But is it time to reconsider this ‘norm’ for the sake of our own health? Not to mention our partners? Scientific research says maybe we should.
As humans, we will all spend around a third of our lives asleep. Or at least try to. According to the National Institute of Neurological Disorders and Stroke in the United States, about 60 million people a year report suffering either long-term or occasional sleep disturbances. That’s nearly one fifth of the entire population of the US.
So it’s not surprising that a large amount of money is spent not only on sleep research, but also on consumer sleep products. Indeed, the industry is now worth in excess of $32 billion a year.
Are sleep researchers missing the obvious?
But this paradigm of research and expenditure often misses a crucial point. People don’t sleep alone. Traditionally, acquiring a sleep partner has been viewed as a rite of passage to adulthood. Despite such a drastic life change, we’re unlikely to stop and think about whether it could effect our health. However, research is starting to reveal that our sleep patterns can change when we bunk up. Indeed it may have significant effects on our lives – good and bad.
Scientific research concerning the effects of sleeping with a bed partner, (aka dyadic-sleep), is limited, but not insignificant.
Physiological effects
Sleep studies that measure brain-wave activity or body movement, have shown that sharing a bed results in worse sleep quality compared to sleeping alone. More specifically, dyadic sleepers experience less REM sleep and increased physical activity during the night, compared to those who sleep alone.
So does sharing a bed mean equate to poorer sleep? It’s not that simple.
Emotional factors
Despite evidence hinting at the potential harm to sleep quality, participants generally report being more satisfied with their sleep when sleeping together with their partner rather than alone.
So how can we explain such divergence between self-reported evidence and the lab results? Researchers at the University of Utah suggest that in order to answer this question we need to understand the relationship between partners.
In 2008 Lisa Diamond and colleagues investigated what happens when romantic partners are temporarily separated. They found that some individuals who undergo ‘travel-related separations’ showed increased attachment anxiety.
Although it’s more commonly associated with young children, attachment anxiety can also have a significant impact in adulthood. And according to the researchers, it can act impact on sleep quality during the separation phase.
Hence one possible reason that you sleep better with your partner is that your attachment leads to feelings of anxiety when you are apart.
Overall then, while dyadic sleep appears to decrease sleep quality, (using objective sleep measurements), separation from your partner actually exacerbates sleep problems because of the effects of attachment anxiety.
Syncing with your partner
But that’s not the only way couples can affect each other’s sleep quality. Apart from core sleep times, spouses may have a direct effect on sleep by acting as social time keepers. This is because partners have an influence on both meal times and pre-bedtime rituals during the day. These factors have been shown to have a significant impact on our internal body clock.
One study found that similarity in sleep-wake rhythms can predict the strength of a couple’s relationship. Couple’s whose sleep-wake preferences were “mismatched” were found to have worse sleep quality that those who had more similar sleeping patterns. In other words, couples who naturally wake up and go to bed at similar times have been found to be more satisfied in their relationship.
So there we have it. To have the optimum sleep, it’s possible that nothing beats that of the bachelor’s life. But if you are planning on moving in with your partner, it might be worth finding out about when they plan on getting up in the morning.
Updated October 23rd 2017
Breathing through you mouth, rather than your nose, can come with a host of unpleasant symptoms.
What is mouth breathing?
Though mouth breathing happens for different reasons in adults and children, the culprit is usually a nasal obstruction. When we breathe normally through the nose, the air we take in is warmed and moistened before it gets to our lungs. If a person has difficulty breathing through the nose, however, he or she is forced to take in cold, dry air through the mouth.
What causes it?
Essentially an incorrect form of respiration, mouth breathing can happen for a number of reasons. “Some kids do it out of habit,” explains Dr. Veronique Benhamou, director of periodontology at McGill University in Montreal. “Their bite may be off, or the position of the jaw and teeth may be such that when they sleep, their lips don’t quite close.”A child may also suffer from abnormally large tonsils, which can obstruct breathing.
Dr. Harry Hoediono, president of the Ontario Dental Association, says mouth breathing may also occur as a result of a birth defect, like a deviated septum, that may make it more difficult to breathe through the nose. “It could even be a skeletal deformity that has never been picked up on, but that makes it easier for someone to breathe if they lean forward and breathe through their mouth,” he explains.
Dr. Hoediono also says that some people, especially older people, can end up mouth breathing as a result of taking medication, a condition called xerostomia. “In these cases, the dryness can be painful. It can feel like the mouth is burning,” he says. Mouth breathing can also develop after glands are damaged during chemotherapy and radiation treatments.
Why is it a problem?
One of the most common side effects of mouth breathing is an excessively dry mouth. Under normal conditions, saliva continuously washes bacteria from the mouth. If your mouth is dry, however, that bacteria can more readily take hold and cause problems like cavities. “That’s because dry membranes are easier to invade,” explains Dr. Hoediono.
In children, mouth breathing can also lead to permanent skeletal deformities. That’s because it promotes the growth of the upper jaw, rather than the lower jaw. ‘The result is a large overbite and a gummy smile.’
Dr. Hoediono says that mouth breathing can also cause sleep difficulties, causing people to wake in the night if they aren’t getting enough oxygen. In children, lack of sleep may reduce their ability to pay attention and concentrate at school, which may be mistaken for attention deficit disorder. In adults, mouth breathing can be related to sleep apnea, which causes people to wake frequently at night. “You can end up feeling exhausted the next day,” says Dr. Hoediono.
Signs of mouth breathing
Dr. Benhamou says that while a natural mouth breather may be able to stave off dryness by remoistening the mouth throughout the day, it will get dry overnight. “Because you are breathing through your mouth all night, you dry out the soft tissues,” she explains. Mouth breathers often have chronically red and inflamed gums, even if their oral health is otherwise good. Adults may also find they have bleeding gums, or may get frequent cavities.
Dr. Hoediono says another sign is if the back of your throat feels dry and itchy when you wake up, or there’s a burning sensation. ‘When you wake up, put a finger over one nostril and try to breathe in while keeping your mouth closed, and then try it on the other side. Any difficulty inhaling could indicate a problem with blocked nasal passageways.’
Because it is so drying, mouth breathing can also cause chronic bad breath. “People tell me they brush their teeth constantly or they chew gum, but the bad breath is still there,” says Dr. Hoediono.
What to do if you’re a mouth breather
Dr. Benhamou says it’s important to determine why the mouth breathing is happening before you can correct it. “If the cause is huge tonsils, then removing them might be an option,” she says. If the problem is structural and a child can’t, for example, close his lips over flared front teeth, then the solution may be orthodontic treatment.
Using a humidifier while sleeping can help ease mouth dryness, as can replenishing with lots of fluids. Dr. Benhamou sometimes suggests patients rub a small amount of vitamin E oil on their gums before bedtime to keep them from drying out overnight.
Dr. Hoediono says a thorough dental exam will help determine whether mouth breathing is a problem. It’s also important for parents to look for signs of mouth breathing in children, so the problem can be corrected before it worsens. “I had a mother bring a child in,’ he recalls. “She had parched gums, a dry mouth, an overbite and an obstruction of the nasal passages,” a classic mouth breather. I referred her to a doctor and they sent her for surgery. They removed a nasal obstruction, and not long after, she was feeling better and doing better at school!”
Updated October 22nd 2017
We’re told to have power naps to keep us safe on the road and improve our alertness if we’ve had insufficient sleep. They even help our surgeons stay awake during long shifts. But siestas and nana naps can also leave us feeling groggy and lethargic. So are they healthy or harmful? First, let’s look at the benefits.
Many people experience overwhelming sleepiness during the mid-afternoon while reading or working on the computer. Taking the time for a brief nap will almost immediately relieve this feeling and improve alertness for a few hours after waking.
A brief nap can not only reduce sleepiness but also improve cognitive functioning and psychomotor performance (the brain telling the body to move). A few minutes of shut-eye also considerably enhances short-term memory and mood.
These benefits are similar to those experienced after consuming caffeine (or other stimulant medications), but without the side effects of possibly disrupted night time sleep or developing caffeine dependence.
Optimal length of a power nap
The length of the nap is very important in determining its subsequent effect on alertness and cognitive functioning. Although naps of all durations (from five minutes to two hours) have been shown to have some benefits to alertness, the way in which these benefits emerge after waking up varies according to length of nap.
The benefits of a brief nap (up to 20 minutes) emerge almost immediately following the nap and can last up to three hours.
The alerting benefits of long naps (one to two hours) however, are delayed after waking but typically last longer. The improvements in alertness and performance following a long nap can still be experienced up to 24 hours after waking.
But after waking from a long nap, individuals typically feel sleepy and groggy for a short while before feeling refreshed and rejuvenated. This feeling is called sleep inertia and reflects a transition from a sleep state to an awake state and can last up to 30 minutes.
The magnitude of sleep inertia depends on several factors, the most important being the amount of deep sleep (also known as slow-wave sleep) within the napping episode. Since slow-wave sleep develops gradually (over time spent asleep), awakening from a longer nap usually produces longer and more intense periods of sleep inertia.
Brief naps are associated with shorter periods of sleep inertia, and for very brief naps (five to ten minutes), no sleep inertia at all.
It’s also worth mentioning that long naps contain more deep (or slow wave sleep) than shorter naps. So when long naps are taken in the afternoon, it can be more difficult to sleep that night.
What’s the best time for a nap?
The rejuvenating effects of a brief nap are also influenced by when the nap is taken and how long an individual has been awake prior to the nap.
Brief naps taken in the early afternoon, at about 2pm, have a greater recuperative value than when taken at any other time of the day.
Research has also established the longer an individual has been awake, the longer a nap needs to be to improve alertness. Brief naps taken after long periods of wakefulness (18 hours or more) are less effective and have shorter-lasting benefits than naps taken after shorter periods of wakefulness. So it’s unlikely that a single brief nap could replenish alertness after a night of total sleep loss.
Benefits of the power nap
The benefits of naps are well established and can be used in a variety of situations to regain alertness and minimise feelings of sleepiness.
Brief “power” naps are ideal in the work place as they can be taken during an employee’s break time. The almost immediate improvements to alertness, with minimal sleep inertia, allow maximum productivity to resume almost immediately after waking from the nap.
Napping can also help overcome jet lag following travel across time zones. A brief daytime nap can be used to alleviate sleepiness when trying to save your long sleep for the night at your destination.
Research has also suggested impressive potential for brief naps to reduce excessive levels of daytime sleepiness experienced by narcolepsy and sleep apnoea sufferers.
So instead of reaching for a cup of coffee the next time sleepiness creeps up on you in the afternoon, use the time for a brief nap and enjoy feeling refreshed and rejuvenated without interfering with your night’s sleep.
Nicole Lovato
Leon Lack
Updated October 22nd 2017
We’re often told by the popular press and well-meaning family and friends that, for good health, we should fall asleep quickly and sleep solidly for about eight hours – otherwise we’re at risk of physical and psychological ill health.
There is some evidence to suggest that those who consistently restrict their sleep to less than six hours may have increased risk of cardiovascular disease, obesity and diabetes. The biggest health risk of sleep deprivation comes from accidents, especially falling asleep while driving.
Sleep need varies depending on the individual and can be anywhere from 12 hours in long-sleeping children, to six hours in short-sleeping healthy older adults. But despite the prevailing belief, normal sleep is not a long, deep valley of unconsciousness.
The sleep period is made up of 90-minute cycles. Waking up between these sleep cycles is a normal part of the sleep pattern and becomes more common as we get older.
It’s time to set the record straight about the myth of continuous sleep – and hopefully alleviate some of the anxiety that comes from laying in bed awake at night.
So what are the alternatives to continuous sleep?
The siesta
The siesta sleep quota is made up of a one- to two-hour sleep in the early afternoon and a longer period of five to six hours late in the night. Like mammals and birds, humans tend to be most active around dawn and dusk and less active in the middle of the day.
It’s thought the siesta was the dominant sleep pattern before the industrial revolution required people to be continuously awake across the day to serve the sleepless industrial machine. It’s still common in rural communities around the world, not just in Mediterranean or Latin American cultures.
Our siesta tendency or post-lunch decline of alertness still occurs in those who never take afternoon naps. And this has less to do with overindulging at lunchtime and more to do with our circadian rhythms, which control our body clock, hormone production, temperature and digestive function over a 24-hour period.
Bi-phasic sleep
Historical records also suggest that a segmented or bi-phasic sleep pattern was the norm before the industrial revolution. This pattern consists of an initial sleep of about four and a half hours (three sleep cycles of 90 minutes each) followed by one to two hours of wake and then a second sleep period of another three hours (another two sleep cycles).
During the winter months, northern Europeans would spend nine or ten hours in bed, with two to three hours of it spent awake, either in one long mid-night period or several shorter wake periods across the night.
The bed was the cheapest place to keep warm and was considered a place of rest as well as sleep. A few hours of wakefulness certainly wouldn’t have been considered abnormal or labelled as insomnia.
Can’t sleep? Don’t worry
These days we expect to have close to 100% of our time in bed asleep, dozing off within minutes and not waking at all until the alarm sounds. Unfortunately this myth sets us up for worry if we find ourselves awake in the middle of the night. And this worry can lead gradually to the development of insomnia.
Humans can sleep on very different schedules, with little difference in wakeful competence. International sleep researchers have trialled a number of different sleep schedules: sleep for 20 minutes every hour; one hour sleep every three hours; ten hours sleep every 28 hours. Participants survive easily on all these schedules despite their impracticality in our 24-hour world.
The best quality sleep is obtained during our circadian low phase – when body temperature and metabolic rate are at their lowest. For most people, this occurs late at night. But just like other species, humans can be opportunistic sleepers and satisfy our need for sleep when we get the opportunity.
There’s no doubt that the eight-hour solid sleep myth is a relatively recent cultural imposition. And although it satisfies our modern lifestyle, it does have its disadvantages.
Some have lamented the loss of wakefulness between sleep cycles as a valuable time of contemplation or creativity.
But probably the greatest negative impact of the eight-hour sleep myth is its power to create insomniacs out of good sleepers who experience normal awakenings across the night.
Leon Lack
Updated October 21st 2017
Many of us don’t get enough sleep on a regular basis. It might be due to a sleep disorder, busy social life, new baby, long working hours, shift work or just staying up too late binge-watching Netflix. But not getting enough quality sleep can have significant implications for health. Large survey studies that ask about sleep habits and health show sleeping less than six or seven hours on average per night increases the risk for obesity, type 2 diabetes and heart disease.
A growing body of research is beginning to show how habitual inadequate sleep might alter our physiology and lead to the development of chronic disease. The three main areas of response to sleep deprivation that have been examined are metabolic (processing and using energy from food), immune (protection against disease) and heart function.
To examine how these systems react to sleep deprivation in healthy people, volunteers are recruited to studies that require them to live in a laboratory environment from several days to weeks. Their sleep time is manipulated and access to food and drink, light, temperature, physical activity and social interaction are all controlled.
In these studies, participants may go without sleep for one or several nights (total sleep deprivation) or reduce sleep time for several weeks (partial sleep deprivation) to examine the impacts of changes to sleep duration on metabolic, immune and heart function.
Metabolic and endocrine responses.
A good deal of research suggests sleep loss impairs glucose metabolism, the process in which sugars from food intake is processed and stored or used to produce energy. Laboratory studies have consistently found short-term sleep loss decreases glucose tolerance and insulin sensitivity in healthy, young, lean adults.
If long-term, these changes to glucose metabolism could increase the risk of obesity and type 2 diabetes. Combine this with the tendency when sleep-deprived to eat comforting foods, which are higher in fat and sugar, and it’s no wonder people who are sleep-deprived find it harder to lose weight than those who are well rested.
What’s more, both total and partial sleep deprivation have also been found to modify the normal daily rhythms of appetite-regulating hormones. Leptin, a hormone that suppresses appetite, and ghrelin, a stomach-derived peptide that stimulates appetite, both change in response to sleep deprivation. When you do not get enough sleep, changes in these appetite-regulating hormones and an increase in food consumption could lead to weight gain and obesity.
These laboratory results have also been found in a large population-based longitudinal study of sleep patterns known as the Wisconsin Sleep Cohort. In this study, participants reported their sleep habits through questionnaires and sleep diaries and provided a blood sample on one morning, prior to eating, to evaluate leptin and ghrelin levels.
In this study, the people sleeping less than eight hours a night (74.4% of the sample) had an increased body mass index (BMI). Habitual short sleep was also associated with low leptin and high ghrelin. Since reduced leptin and elevated ghrelin are likely to increase appetite, this may explain the increased BMI observed and how insufficient sleep could contribute to developing obesity.
Immune responses.
Healthy sleep helps to maintain appropriate immune function. Sleep loss may lead to alterations in immune function, resulting in inflammatory disease, an increased risk of cancer and infectious disease. One night of total sleep deprivation has been found to cause a reduction of natural immune responses. Total sleep deprivation has also been shown to elevate certain inflammatory markers that may lead to insulin resistance, heart disease and osteoporosis. In one interesting laboratory study, partial sleep deprivation (six nights of only four hours’ sleep per night) at the time of a vaccination was found to reduce the number of antibodies by more than 50% ten days after sleep-deprived participants received a flu shot. This shows that adequate sleep is needed for optimal response to infectious disease.
Heart health.
The prevalence of high blood pressure has increased in the last few decades. Over this period, habitual sleep duration has decreased. Recent studies have shown there is a relationship between sleep deprivation and high blood pressure and heart disease.
The Nurses’ Health Study, one of the largest and longest-running studies assessing influences on women’s health, found the risk of developing heart disease was increased in women who slept less than five hours (short sleepers) and more than nine hours (long sleepers).
Some potential reasons for the relationship between decreased sleep duration and heart disease may be sympathetic overactivity (bodily systems involved in the stress response commonly known as the fight-or-flight response), increases in blood pressure, or decreased glucose tolerance.
Another potential mechanism that might link sleep loss and heart disease is through the activation of C-reactive protein, a protein raised in response to inflammation. C-reactive protein is a marker shown to be predictive of poor heart health. It is elevated in healthy adults following both total sleep deprivation and a week of partial sleep deprivation.
The news isn’t all bad though.
There is some evidence that by improving sleep we can reduce the impact of sleep loss and reverse its negative effects. Habitually extending sleep, taking naps and using weekends and days off to “catch up” on sleep may lessen the long-term adverse health impacts of sleep loss.
Siobhan Banks
Crystal Grant
Updated October 20th 2017
Many of us have experienced the effects of sleep deprivation: feeling tired and cranky, or finding it hard to concentrate. Sleep is more important for our brains than you may realise.
Although it may appear you're "switching off" when you fall asleep, the brain is far from inactive. What we know from studying patterns of brain electrical activity is that while you sleep, your brain cycles through two main types of patterns: rapid eye movement (REM) sleep and slow-wave sleep. Slow-wave sleep, which occurs more at the beginning of the night, is characterised by slow rhythms of electrical activity across large numbers of brain cells (occurring one to four times per second). As the night progresses, we have more and more REM sleep. During REM sleep we often have vivid dreams, and our brains show similar patterns of activity to when we are awake.
What are our brains doing while we sleep?
Sleep serves many different functions. One of these is to help us remember experiences we had during the day. REM sleep is thought to be important for emotional memories (for example, memories involving fear) or procedural memory (such as how to ride a bike). On the other hand, slow-wave sleep is thought to reflect the storing of so-called "declarative" memories that are the conscious record of your experiences and what you know (for example, what you had for breakfast).
We also know experiences are "replayed" in the brain during sleep and the memories of these experiences are like segments from a movie that can be rewound and played forward again. Replay occurs in neurons in the hippocampus — a brain region important for memory — and has been best studied in rats learning to navigate a maze. After a navigation exercise, when the rat is resting, its brain replays the path it took through the maze. Replay helps to strengthen the connections between brain cells, and is therefore thought to be important for consolidating memories. But is it that important for you to remember what you had for breakfast? Probably not — that's why the brain needs to be selective about what it remembers.
Sorting the wheat from the chaff.
Sleep allows the brain to sift through memories, forgetting certain things so as to remember what's important. One way it may do this is by "pruning away" or "scaling down" unwanted connections in the brain.
A leading theory of sleep function — the "synaptic homeostasis hypothesis" — suggests that during sleep there is a widespread weakening of connections (known as "synapses") throughout the brain. This is thought to counterbalance the overall strengthening of connections that occurs during learning when we are awake. By pruning away excess connections, sleep effectively "cleans the slate" so we can learn again the next day.
Interfering with this scaling down process can, in some cases, lead to more intense (and perhaps unwanted) memories. The importance of sleep for keeping our brains optimally active may be reflected in our changing sleep patterns as we age. Babies and children sleep much more than adults, probably because their developing brains are learning much more, and being exposed to new situations. Later in life, sleep declines and becomes more fragmented. This may reflect either a reduced need for sleep (as we are learning less) or a breakdown in sleep processes as we age.
Sleep is also needed to do a bit of brain "housekeeping". A recent study in mice found sleep cleanses the brain of toxins that accumulate during waking hours, some of which are linked to neurodegenerative diseases. During sleep, the space between brain cells increases, allowing toxic proteins to be flushed out. It's possible that by removing these toxins from the brain, sleep may stave off neurodegenerative diseases like Alzheimer's.
What happens if we have a bad night's sleep?
Getting enough sleep is important for attention and learning during our waking hours. When we are sleep deprived, we can't focus on large amounts of information or sustain our attention for long periods. Our reaction times are slowed. We are also less likely to be creative or discover hidden rules when trying to solve a problem.
When you haven't had enough sleep, your brain may force itself to shut down for a few seconds when you're awake. During this "micro-sleep" you may become unconscious for a few seconds without knowing it. Drowsiness while driving is a leading cause of motor vehicle accidents, with sleep deprivation affecting the brain just as much as alcohol. Sleep deprivation can also lead to fatal accidents in the workplace — a major issue in shift workers.
The beneficial effects of sleep on attention and concentration are particularly important for children, who often become hyperactive and disruptive in class when they don't have enough sleep. One study found getting just one hour less sleep per night over several nights can adversely affect a child's behaviour in class.
What are the long-term effects?
The longer-term effects of sleep deprivation are more difficult to study in humans for ethical reasons, but chronic sleep disturbances have been linked to brain disorders such as schizophrenia, autism and Alzheimer's. We don't know if sleep disturbances are a cause or symptom of these disorders. Overall, the evidence suggests having healthy sleep patterns is key to having a healthy and well-functioning brain.
Leonie Kirszenblat. The University of Queensland.
Updated October 19th 2017
Combining REM sleep neuroscience with the psychology of dreaming may help treat depression and more, researcher says.
Rubin Naiman, PhD, clinical assistant professor of medicine and the sleep and dream specialist at the University of Arizona (UA) Center for Integrative Medicine, formed this philosophy over decades as both a psychologist and sleep medicine physician.
Poor sleep, Naiman says, “is inextricably linked to poor dreaming,” the loss of which is caused by a host of factors, some of which are self-inflicted, that are “wreaking havoc on the public health by contributing to illness, depression, and an erosion of consciousness.”
In “Dreamless: The Silent Epidemic of REM Sleep Loss,” a comprehensive data review recently published in the Annals of the New York Academy of Sciences, Naiman explores the causes of rapid eye movement (REM) sleep disruption and contends many common health concerns attributed to sleep deprivation, such as obesity, cardiovascular disease, and memory loss, may be rooted in a lack of REM dreaming.
Yet most sleep physicians continue to devalue dreaming by discounting its relevance in patient outcomes.
“I began to realize that most of my colleagues in sleep medicine had as much disregard for dreaming as my psychology colleagues had for the science of REM sleep,” he says. “So, my interest, for years, has been in trying to triangulate the dream: Let’s see what dreaming is like if we look at it from both the neuroscience of REM sleep and the psychology of dreaming.”
Generally speaking, people sleep in stages that make up 90-minute cycles. Most adults experience 4 to 6 cycles per 7 hours of sleep. With each cycle, we experience less deep sleep and more REM sleep, and so we typically dream more in the early morning hours. Hence, REM sleep occurs after deeper, restorative, non-REM sleep, which is prioritized by the body.
In reviewing the data, Naiman focused on medication and substance use, common sleep disorders, and behavioral and lifestyle factors in REM sleep and dream loss. Emerging evidence, he says, suggests REM dreaming “mediates immune function, memory consolidation, and mood regulation, as well as transpersonal, religious, and personal experiences,” while too little may increase inflammatory response.
In the United States, Naiman notes, major factors in REM sleep and dream loss are commonly used—and in some cases, abused—substances, including medications, alcohol, and cannabis.
While a glass of wine with dinner or occasional marijuana use is probably fine, he warns it is unclear what impact newer hybrid varieties of cannabis may have on REM dream loss. Marijuana “is very seductive, because some strains can help people fall asleep,” he says. “But in the long run, just like alcohol, it interferes with REM sleep.”
Many common prescription and over-the-counter (OTC) medications also suppress REM sleep, including hypnotics and anticholinergic drugs. Worse, in Naiman’s view, at least in terms of dream loss, are antidepressants. Naiman, for one, says the drugs are over-prescribed: “I believe depression can actually be a healing response that can help us achieve a natural balance of REM sleep. [Antidepressants] are necessary in cases of severe depression—because if you relieve the pressure to dream altogether, you will see immediate relief. But if you take an aspirin to cut a fever, while you may feel better, you are actually undermining the endogenous healing response.”
Though rarely acknowledged, common sleep disorders like insomnia, insufficient sleep syndrome, and sleep apnea cause REM dream loss, Naiman says. Behavioral and lifestyle factors also play large roles, especially excessive light at night and routine alarm clock awakenings. “The solution to all of this is lifestyle change. And that is easily said, but not easily done,” Naiman says.
Meanwhile, a national emphasis on “dream promotion” is needed “to call attention to the fact that we are not dreaming well, and that dreams are important,” Naiman says. “We know, for example, that melatonin increases REM sleep. But we need to very systematically [examine] what ‘dream promotion’ does to waking life. And more specifically, is it possible that restoring REM sleep may help treat depression?”
A lot could be accomplished via the mainstream press, which in recent decades has become quick to report on news surrounding sleep deprivation, Naiman says, as well as social media and public health education campaigns funded by government agencies and professional organizations in sleep medicine. Dream promotion, however, really begins with the provider-patient relationship, he says.
“I think it is critical that sleep docs start paying attention to their own dreams and to the dreams of their patients. They need to not only focus on increasing sleep time and sleep continuity, but also on making sure there is a healthy restoration of REM sleep, so their patients understand it is important,” he says.
“We don’t ask patients about dreaming if we don’t pay attention to our own dreams,” concludes Naiman, who has been teaching medical students to see the value in dreaming for the past 15 years. “I will often tell them, ‘You know, even if you only have a couple of minutes, just ask your patient, ‘Are you dreaming?’”
Chuck Holt
Updated October 19th 2017
