Your weirdest dreams could be a sign your brain is doing something unexpected.
On your side, face-up or face-down? The position which best clears metabolic waste from your brain at night.
On your side, face-up or face-down? The position which best clears metabolic waste from your brain at night.
Sleeping on your side removes waste from the brain most efficiently.
As a result, sleeping on your side may help reduce the risk of Alzheimer’s and other neurological diseases.
Professor Maiken Nedergaard, one of the study’s authors, said:
“It is interesting that the lateral sleep position is already the most popular in human and most animals — even in the wild — and it appears that we have adapted the lateral sleep position to most efficiently clear our brain of the metabolic waste products that built up while we are awake.
The study therefore adds further support to the concept that sleep subserves a distinct biological function of sleep and that is to ‘clean up’ the mess that accumulates while we are awake.
Many types of dementia are linked to sleep disturbances, including difficulties in falling asleep.
It is increasing acknowledged that these sleep disturbances may accelerate memory loss in Alzheimer’s disease.
Our finding brings new insight into this topic by showing it is also important what position you sleep in.”
The study of mice tested the brain’s ‘clean-up’ mechanism in three different sleeping positions:
Scientists monitored how cerebrospinal fluid (CSF) flowed through the brain and exchanged with interstitial fluid.
This pathway — called the glymphatic pathway — clears waste from the brain most efficiently at night.
Professor Helene Benveniste, another of the study’s authors, said:
“The analysis showed us consistently that glymphatic transport was most efficient in the lateral position when compared to the supine or prone positions.
Because of this finding, we propose that the body posture and sleep quality should be considered when standardizing future diagnostic imaging procedures to assess CSF-ISF transport in humans and therefore the assessment of the clearance of damaging brain proteins that may contribute to or cause brain diseases.”
The research was published in the Journal of Neuroscience (Lee et al., 2015).
For some, apps designed to improve sleep actually make it worse.
Even good sleepers frequently experience insomnia.
Even good sleepers frequently experience insomnia.
Around one-quarter of Americans who are ‘good sleepers’ experience acute insomnia each year.
However, without treatment 75 percent recover without developing persistent sleep problems.
Of the rest, 21 percent went on to experience recurring bouts of insomnia and the remaining 4 percent developed chronic insomnia.
Insomnia is defined as having trouble falling asleep or staying asleep for at least three nights a week over two weeks.
The condition becomes chronic when it continues for three months.
Dr Michael Perlis, study author, said:
“Whether caused by stress, illness, medications, or other factors, poor sleep is very common.
These findings reveal new insights about the paths that acute insomnia takes and can inform interventions that target poor sleep and help people recover sustained sufficient sleep.”
The study tracked 1,435 adults for a year.
All were initially defined as ‘good sleepers’: able to fall asleep within 15 minutes and not remaining awake for more than 15 minutes during the night.
The study’s authors conclude:
“The incidence rate of acute insomnia (3 or more nights a week for between 2 and 12 weeks) is remarkably high.
This said, most incident cases resolve within a few days to weeks. Incident chronic insomnia only occurs in about 2 in 100 individuals.”
So, why is insomnia so common?
Insomnia in response to stressful situations may have helped keep our ancestors alive — after all, it is sub-optimal to be fast asleep in your cave when a pack of wolves is outside.
The study’s authors explain:
“…it is possible that AI [acute insomnia] may be normative (i.e. expected as part of the natural rhythm of sleep/insomnia), if not adaptive.
One way this might be true is that the AI that occurs with stress may be an unrecognized part of the fight-flight response; a necessary override to the normal two process regulation of sleep timing, depth and/or duration.
Put differently, stress induced insomnia may prohibit the systematic imperative for sleep under unsafe conditions.”
Unfortunately, knowing that periodic insomnia is normal does not make it any less unpleasant.
The study was published in the journal Sleep (Perlis et al., 2019).
From “aha” moments to a 50 percent lower stroke risk, science proves that napping isn’t lazy — it’s a biological necessity for peak performance.
This nutrient helped children sleep an hour longer.
The precise mechanism by which a brief afternoon rest resets your brain’s learning capacity.
Scientists followed 1,800 people’s sleep and diet over one year.
Scientists followed 1,800 people’s sleep and diet over one year.
A high-fat diet is linked to greater daytime drowsiness, finds a study of 1,800 men aged 35-80.
Researchers monitored participants’ eating and sleeping habits over a year.
Dr Yingting Cao, the study’s first author, said:
“After adjusting for other demographic and lifestyle factors, and chronic diseases, we found that those who consumed the highest fat intake were more likely to experience excessive daytime sleepiness.
This has significant implications for alertness and concentration, which would be of particular concern to workers.
High fat intake was also strongly associated with sleep apnea.”
The researchers found that 41 percent of the men had experienced daytime sleepiness.
Dr Cao said:
“Poor sleep and feeling sleepy during the day means you have less energy, but this in turn is known to increase people’s cravings for high-fat, high-carbohydrate foods, which is then associated with poor sleep outcomes.
So the poor diet-and-sleep pattern can become a vicious cycle.
The simple message is a common-sense one, but we need more people to pay attention to it: we need to eat better; a good sleep the night before is best.”
The study was published in the journal Nutrients (Cao et al., 2016).
These common foods could be sabotaging your rest.
A good habit that boosts attention, decision-making and the ability to resist impulses.
A good habit that boosts attention, decision-making and the ability to resist impulses.
Good sleep habits can boost attention, decision-making and the ability to resist impulses.
Good sleep habits include going to bed at the same time every night, avoiding caffeine late in the day and allowing time to mentally wind-down before bedtime.
Professor June Pilcher, who led the study, said:
“Self-control is part of daily decision-making.
When presented with conflicting desires and opportunities, self-control allows one to maintain control.
Our study explored how sleep habits and self-control are interwoven and how sleep habits and self-control may work together to affect a person’s daily functioning.”
Professor Pilcher explained the review’s conclusions:
“Poor sleep habits, which include inconsistent sleep times and not enough hours of sleep, can also lead to health problems, including weight gain, hypertension and illness, according to prior research.
Studies have also found that sleep deprivation decreases self-control but increases hostility in people, which can create problems in the workplace and at home.”
Since sleep and self-control are so intimately connected, improving sleep can help in many ways, Professor Pilcher said:
“Many aspects of our daily lives can be affected by better-managed sleep and self-control capacity.
Improved health and worker performance are two potential benefits, but societal issues such as addictions, excessive gambling and over spending could also be more controllable when sleep deficiencies aren’t interfering with one’s decision making.”
The study was published in the journal Frontiers in Human Neuroscience (Pilcher et al., 2015).
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