Studies show that at least 7 hours of sleep are needed, each night, by adults

Living under a flight path, along which aircraft fly at below – say 7,000 feet – is noisy. It is all the more noisy now that the aviation industry is introducing narrow, concentrated flight paths. These are replacing the older more dispersed routes, as aircraft have new “PBN” technology (like car satnav) and can fly far more accurately than in the past. And it suits the air traffic controllers to keep flight paths narrow. But if airports allow flights at night, or if the “night” period when flights are not allowed is short, this has consequences for people living near, or under, routes. Studies carried out scientifically show adults need at least 7 hours of sleep, each night to be at their healthiest. Children and teenagers need more.There are some people who need more than 7 hours per night, and some need less. It is not good enough to get less one night, and more the next – the brain does not process the day’s memories adequately. Studies show adverse effects of not getting enough sleep, which are not only related to concentration, speed of thinking or reacting etc, but also medical effects. The concentrated flight paths, and airports allowed to have flights all night, are causing very real problems. A study into noise and sleep by the CAA in 2009 looked at the issue, and said a large and comprehensive study is needed, but it is “likely to be expensive.”


Aviation background:

Some airports allow flights all night. The numbers of flights at Heathrow, Gatwick and Stansted are controlled by the DfT. The current regime remains in place till 2017. There is also a “quota count” system in place, by which the noisiest planes score more points, and airports have a limit of points they can rack up during a year. That limits flights at night, especially by the older and noisier planes.

Flights at night disturb people’s sleep.  This may have health implications, as well as quality of life implications.  On average people need at least 7 hours of sleep per night, with many people needing  8 hours or more.  Children, the elderly and people who are not well may need more.  The Department of Transport regards “night” as being the 8 hour period from 23.00 to 07.00 local time.

The DfT imposes quotas on the number of night flights at Heathrow, Gatwick and Stansted.   They also set quotas on the number of noise points that each airport is allowed each year (the noisier aircraft score more points).  This is for the “night quota period” which is the six and a half hour period from 23.30 to 06.00.  That is nowhere near the 8 hours of quiet time that people may need.  The DfT regards the time between 23.00 and 23.30 and 06.00 to 07.00 as “shoulder” periods, when there can be more flights.

A review of these quotas, which was due in 2012, has been postponed until 2017.

Not everyone can plan their life so they go to bed and sleep at the times when there are restricted flights. It may not suit people to got to sleep at 11.30pm and wake at 6am. Many people go to bed much earlier – or sleep till later.  A period of six and a half hours, as well as being too short even for those who sleep those hours, is far from adequate for those who choose to go to bed earlier or later.

East Midlands airport has the most night flights in the UK, many of them noisy and elderly cargo planes.  While the legal cap on night flights at Heathrow is 5,800 per year, it is 14,450 at Gatwick, and 12,000 at Stansted ( though about 8,000 actually flew).

Gatwick has about 50 flights each night in summer (11pm to 6am); Heathrow has about 16 (11.30pm – 6am) throughout the year but they tend to be noisier, large long-haul aircraft, which have arrived from the far East or South Africa.  Stansted has around 22 flights per night.

Airlines like to have some night flights in order to maximise profits, using the plane the highest number of “rotations” per day, or so long haul flights can arrive very early in the morning.


amount of sleep needed

How Much Sleep Do We Really Need?

Humans, like all animals, need sleep, along with food, water and oxygen, to survive. For humans sleep is a vital indicator of overall health and well-being. We spend up to one-third of our lives asleep, and the overall state of our “ sleep health ” remains an essential question throughout our lifespan.

Most of us know that getting a good night’s sleep is important, but too few of us actually make those eight or so hours between the sheets a priority. For many of us with sleep debt , we’ve forgotten what “being really, truly rested” feels like.

To further complicate matters, stimulants like coffee and energy drinks, alarm clocks, and external lights—including those from electronic devices—interferes with our “ circadian rhythm ” or natural sleep/wake cycle.

Sleep needs vary across ages and are especially impacted by lifestyle and health. To determine how much sleep you need, it’s important to assess not only where you fall on the “sleep needs spectrum,” but also to examine what lifestyle factors are affecting the quality and quantity of your sleep such as work schedules and stress.

To get the sleep you need, you must look at the big picture.

How Much Sleep Do We Really Need: Revisited

We at the National Sleep Foundation make it our mission to champion not only sleep science, but sleep health for the individual. And so, on the eve of our 25 th anniversary, we are releasing the results of a world-class study that took more than two years of research to complete – an update to our most-cited guidelines on how much sleep you really need at each age.

Click here for a downloadable recommended sleep times chart.

Eighteen leading scientists and researchers came together to form the National Sleep Foundation’s expert panel tasked with updating the official recommendations. The panelists included six sleep specialists and representatives from leading organizations including the American Academy of Pediatrics, American Association of Anatomists, American College of Chest Physicians, American Congress of Obstetricians and Gynecologists, American Geriatrics Society, American Neurological Association, American Physiological Society, American Psychiatric Association, American Thoracic Society, Gerontological Society of America, Human Anatomy and Physiology Society, and Society for Research in Human Development.  The panelists participated in a rigorous scientific process that included reviewing over 300 current scientific publications and voting on how much sleep is appropriate throughout the lifespan.

“Millions of individuals trust the National Sleep Foundation for its sleep duration recommendations. As the voice for sleep health it is the NSF’s responsibility to make sure that our recommendations are supported by the most rigorous science,” says Charles Czeisler, MD, PhD, chairman of the board of the National Sleep Foundation and chief of sleep medicine at Brigham and Women’s Hospital, “Individuals, particularly parents, rely on us for this information.”

How Much Sleep Do You Need?

Though research cannot pinpoint an  exact amount of sleep need by people at different ages, our new chart, which features minimum and maximum ranges for health as well as “recommended” windows, identifies the “rule-of-thumb” amounts experts agree upon.

Nevertheless, it’s important to pay attention to your own individual needs by assessing how you feel on different amounts of sleep.

  • Are you productive, healthy and happy on seven hours of sleep? Or does it take you nine hours of quality ZZZs to get you into high gear?
  • Do you have health issues such as being overweight? Are you at risk for any disease?
  • Are you experiencing sleep problems ?
  • Do you depend on caffeine to get you through the day?
  • Do you feel sleepy when driving ?

These are questions that must be asked before you can find the number that works for you.

Sleep Time Recommendations: What’s Changed?

“The NSF has committed to regularly reviewing and providing scientifically rigorous recommendations,” says Max Hirshkowitz, PhD, Chair of the National Sleep Foundation Scientific Advisory Council. “The public can be confident that these recommendations represent the best guidance for sleep duration and health.”

A new range, “may be appropriate,” has been added to acknowledge the individual variability in appropriate sleep durations. The recommendations now define times as either (a) recommended; (b) may be appropriate for some individuals; or (c) not recommended.

The panel revised the recommended sleep ranges for all six children and teen age groups. A summary of the new recommendations includes:

  • Newborns (0-3 months ): Sleep range narrowed to 14-17 hours each day (previously it was 12-18)
  • Infants (4-11 months): Sleep range widened two hours to 12-15 hours (previously it was 14-15)
  • Toddlers (1-2 years): Sleep range widened by one hour to 11-14 hours (previously it was 12-14)
  • Preschoolers (3-5): Sleep range widened by one hour to 10-13 hours (previously it was 11-13)
  • School age children (6-13): Sleep range widened by one hour to 9-11 hours (previously it was 10-11)
  • Teenagers (14-17): Sleep range widened by one hour to 8-10 hours (previously it was 8.5-9.5)
  • Younger adults (18-25): Sleep range is 7-9 hours (new age category)
  • Adults (26-64): Sleep range did not change and remains 7-9 hours
  • Older adults (65+): Sleep range is 7-8 hours (new age category)

…. and it continues ….



How much can an extra hour’s sleep change you?

9 October 2013 (BBC)

The average Briton gets six-and-a-half hours’ sleep a night, according to the Sleep Council. Michael Mosley took part in an unusual experiment to see if this is enough.

It has been known for some time that the amount of sleep people get has, on average, declined over the years.
This has happened for a whole range of reasons, not least because we live in a culture where people are encouraged to think of sleep as a luxury – something you can easily cut back on. After all, that’s what caffeine is for – to jolt you back into life. But while the average amount of sleep we are getting has fallen, rates of obesity and diabetes have soared. Could the two be connected?

We wanted to see what the effect would be of increasing average sleep by just one hour. So we asked seven volunteers, who normally sleep anywhere between six and nine hours, to be studied at the University of Surrey’s Sleep Research Centre.

The volunteers were randomly allocated to two groups. One group was asked to sleep for six-and-a-half hours a night, the other got seven-and-a-half hours. After a week the researchers took blood tests and the volunteers were asked to switch sleep patterns. The group that had been sleeping six-and-a-half hours got an extra hour, the other group slept an hour less.

In the first episode of Trust Me I’m a Doctor, seven volunteers were recruited to take part in an unusual experiment at the Sleep Research Centre at the University of Surrey

While we were waiting to see what effect this would have, I went to the John Radcliffe hospital in Oxford to learn more about what actually happens when we sleep.
In the Sleep Centre, they fitted me up with a portable electro-encephalograph, a device that measures brain wave activity. Then, feeling slightly ridiculous, I went home and had my seven-and-a-half hours of sleep.

The following day I went to discuss what had happened inside my head during the night with Dr Katharina Wulff.

The first thing she pointed out was that I had very rapidly fallen into a state of deep sleep. Deep sleep sounds restful, but during it our brains are actually working hard. One of the main things the brain is doing is moving memories from short-term storage into long-term storage, allowing us more short-term memory space for the next day. If you don’t get adequate deep sleep then these memories will be lost.

You might think: “I’ll cut back during the week and then make up for it at the weekend.” Unfortunately it doesn’t work like that, because memories need to be consolidated within 24 hours of being formed.

Since deep sleep is so important for consolidating memories it is a good idea if you are revising or perhaps taking an exam to make sure that you’re getting a reasonable night’s sleep. In one study, people who failed to do so did 40% worse than their contemporaries.
Deep sleep only lasts for a few hours. My electrode results showed that during the night my brain went through multiple phases of another kind of activity, called REM sleep.

“This is the phase when you are usually paralysed – so you can’t move,” Wulff explained. But the eye muscles are not paralysed, and that’s why it’s called rapid eye movement sleep.”

During REM sleep an extraordinary thing happens. One of the stress-related chemicals in the brain, noradrenalin, is switched off. It’s the only time, day or night, this happens. It allows us to remain calm while our brains reprocess all the experiences of the day, helping us come to terms with particularly emotional events.

We get more REM sleep in the last half of the night. Which means that if you are woken unexpectedly, your brain may not have dealt with all your emotions – which could leave you stressed and anxious. Drinking alcohol late at night is not a good idea as it reduces your REM sleep while it’s being processed in your body.

Back at the University of Surrey our sleep volunteers had finished their second week of the experiment. What we wanted to see was the effect switching from six-and-a-half hours to seven-and-a-half hours, or vice versa, would have on our volunteers.

Computer tests revealed that most of them struggled with mental agility tasks when they had less sleep, but the most interesting results came from the blood tests that were run.

Dr Simon Archer and his team at Surrey University were particularly interested in looking at the genes that were switched on or off in our volunteers by changes in the amount that we had made them sleep.

“We found that overall there were around 500 genes that were affected,” Archer explained. “Some which were going up, and some which were going down.”
What they discovered is that when the volunteers cut back from seven-and-a-half to six-and-a-half hours’ sleep a night, genes that are associated with processes like inflammation, immune response and response to stress became more active. The team also saw increases in the activity of genes associated with diabetes and risk of cancer. The reverse happened when the volunteers added an hour of sleep.

So the clear message from this experiment was that if you are getting less than seven hours’ sleep a night and can alter your sleep habits, even just a little bit, it could make you healthier. “Have a lie-in, it will do you good” – that’s the kind of health message that doesn’t come along very often.


Also (from an American website,, which is part of the National Sleep Foundation):

Think you can learn to survive on less than six hours of sleep a night? Think again. Adults typically need between seven and nine hours of shut-eye a night to function at their best. Between health care expenses and lost productivity, insufficient sleep in the U.S. rings in at an annual cost of about $66 billion.

How come? When you’re awake, a chemical called adenosine builds up in your blood, and when you sleep, your body breaks it down. Skimp on sleep, however, and adenosine builds up in your bloodstream, making you more and more desperate to snooze. Your reaction time slows, which makes you more prone to dangerous mistakes when driving.

A shortage of sleep is to blame for some 100,000 traffic accidents, 76,000 injuries, and 1,500 deaths a year.

And it adds up. Getting just two to three hours too little sleep for a few nights can have the same effect as pulling an all-nighter—yet it’s something that many Americans routinely do. If that doesn’t sound like a big deal, consider this: Staying up for 24 hours straight and then getting behind the wheel is like driving with a blood-alcohol content that deems you legally drunk in all 50 states.

Just like with a credit card or a mortgage, sleep debt eventually has to be repaid. And the more you add to it, the bigger your balance. Sleeping in on the weekends (a common practice) is one way that you might try to combat a shortage of weeknight sleep, but it’s usually not the best strategy. If you have to overcome a one- or two-hour sleep debt, it might work. But if you’re under-sleeping by, say, an hour every night, Monday through Friday, you’ll end up with a whopping five hours of sleep debt by the time Saturday rolls around. And sleeping in too much on Saturdays and Sundays can make things worse by throwing off your regular snooze schedule and making it harder to sleep on Sunday night.

Useful website about sleep 

and some sensible ideas about how to sleep better, which might help those for whom sleeping well is a problem.


ERCD review of aircraft noise and sleep done for the CAA in 2009

ERCD REPORT 0905 Aircraft Noise and Sleep Disturbance: A Review

K Jones


see also

Restrictions on UK ‘night flights’ at Heathrow, Gatwick and Stansted extended until 2017

In the Government’s response to the Airports Commission’s December 2013 interim report, Patrick McLoughlin announced that plans to more than double the number of ‘night flights’ at Heathrow, Gatwick and Stansted airports have been postponed until 2017. Under proposals outlined in the Commission’s interim report the number of planes allowed to land at the airport before 6am each day would have increased from 16 to 35 from 2015. The government now says it wants to ensure “regulatory stability” at south east airports while the Commission makes its final recommendations on which airport should be recommended to be allowed to build a new runway. The government is also extending the ban on “rare movements made by older noisier types of aircraft.” McLoughlin said: “This decision will help give certainty around the night noise environment for those living near the airports, as well as ensuring operational capacity at these airports is not affected pending decisions on any new airport capacity in light of the commission’s final report.” The government has also postponed the Commission’s recommendation for an Independent Aviation Noise Authority.




Aviation Environment Federation response to DfT’s 2nd stage consultation on night noise

The DfT places restrictions on night flying at Heathrow, Gatwick and Stansted airports. These are reviewed every few years, though in 2012 it was decided to just extend the restrictions until October 2014. There have been two phases to the current consultation, for changes after October 2014, with the first consultation ending in April 2013 and the second phase ending on 3rd February 2014.  The DfT believes it should take “account of the findings of the Airports Commission before making any changes to the night restrictions regime.”  They therefore propose not making any significant changes till October 2017. The Aviation Environment Federation (AEF) has responded to the DfT’s 2nd stage consultation. They comment that  there is a need for an evidence-based target to inform a long-term night noise policy. This should be to reduce night noise below the threshold recommended by the WHO to avoid damaging health impacts. Improvements are needed soon, and therefore they oppose the intention not to make changes before 2017. Greater emphasis needs to be given to the health impacts, on which there have been more studies. There also need to be supplementary metrics to measure the impact of night noise and the  performance of the existing night noise regime.