How much sleep is enough?
A Time to Sleep and a Time to Wake
The third chapter of the ancient Book of Ecclesiastes begins with, “There is a time for everything.” It follows by listing fourteen pairs of contrasts, beginning with “a time to be born and a time to die,” and ending with “a time for war and a time for peace.” This passage was popularized in the song “Turn! Turn! Turn!” by Pete Seeger.
This list of contrasts in everyday life is not exhaustive, but they are representative of the whole of life in this world. There are many other significant pairs not in this list. One is a time to sleep and a time to wake.
Sleep Related Issues
On Memory Foam Mattress.Org, the relationship between sleep and health and how it relates to other areas of life, such as work and personal relationships, is the topic of a couple of pages (Sleep Disorder and Fibromyalgia and Unreported Sleep Disorders) and several Blog articles (Snoring Solution: Look to the Pillow, Sleep Apnea and Hypopnea, Digestive Disorders and Sleep Disturbance), and is touched on in most other items, including Memory Foam Mattress Reviews. The role of mattresses is also considered.
This relationship between sleep and other areas of life is a two-way street. How well and how long we sleep affects them, and they affect how well we sleep.
Sleep Information Resources
The question of How much sleep is enough? is addressed by several persons and organizations in books and articles and online. Frankly, there is not total agreement on the answers, but there is general agreement with differences on particulars. The most authoritative sources are the National Sleep Foundation, National Institutes of Health, Mayo Clinic, and Harvard Medical School. There are other authoritative sites, such as WebMD, Prevention Magazine, Kids’ Health, Beds.Org, and many others. A number of bed, bedding and mattress manufacturers have blogs with well-researched articles on sleep.
Up and At It
How in the world did people get up on time to begin their day’s work before alarm clocks were invented? Most of them had enough sleep by dawn. They woke up naturally. This was so common that those who habitually slept in were regarded as slothful, lazy.
Before the industrial age, most went to bed earlier in the evening than modern people do. Usually, the only ones who stayed up late, or all night, were those who had to, such as guards. The exceptions were times of festivities. Some people did stay up habitually to drink and carouse, such as those with idle wealth who did not need to work daily.
Today, many people go to school or work with too little sleep. Many articles in print and on the web describe sleep deprivation as close to an epidemic. There are a number of reasons for this. Some are cultural or social expectations.
One woman who grew up during the Great Depression told how her father, the son of a German immigrant, said that four hours of sleep a night was enough for anyone. It worked for him, so the children did it too – that was until his daughter contracted tuberculosis and had to rest more, even missing the rest of that school year.
How Much Sleep Is Enough?
The answer to this question is not the same for everyone, even for those of the same age, gender, race or ethnicity, and body type. Issues such as health conditions and metabolism influence the amount of needed sleep. Especially important is the quality of sleep we get. Therefore, the hours of needed sleep for each category will be ranges of hours. When a source lists a set number of hours of sleep required for an age group, this is to be taken as an average or median time rather than a precise time for everyone that age.
The most authoritative source about the amount of sleep needed is the National Sleep Foundation (NSF). Besides their article How Much Sleep Do We Really Need?, they have a chart, Sleep Duration Recommendations, from a 2015 research paper, showing how much sleep is needed in nine stages of human life, from newborn to older adult. As may be expected, the core recommendations are in ranges. The ages for each stage are noted, and consecutive ranges overlap. Also noted are hours outside each range which may be appropriate.
SLEEP DURATION RECOMMENDATIONS
|Stage||Ages||May be Appropriate – Under||Recommended hours of sleep||May be Appropriate – Over|
|Newborn||0-3 mos.||11 to 13||14 to 17||18 to 19|
|Infant||4-11 mos.||10 to 11||12 to 15||16 to 18|
|Toddler||1-2 years||9 to 10||11 to 14||15 to 16|
|Pre-School||3-5 years||8 to 9||10 to 13||14|
|School Age||6-13 years||7 to 8||9 to 11||12|
|Teen||14-17 years||7||8 to 10||11|
|Young Adult||18-25 years||6||7 to 9||10 to 11|
|Adult||26-64 years||6||7 to 9||10|
|Older Adult||65+ years||5 to 6||7 to 8||9|
The first thing we notice is that, on-the-average, newborns sleep most of the time, up to ¾ of the day. The needed sleep time drops rapidly until school age, then a gradual decline until older adults. Note the recommended sleep duration for teens, 8 to 10 hours per night with a short as 7 hours and as long as 11 being acceptable.
Surveys and studies show that teens average 7 hours per night or less, and only 6 or 7 out of 100 sleep as long as 8¼ hours. This means that many teenagers suffer sleep deprivation. This adversely affects their ability to learn in the classroom, and to make sound judgments, such as when driving. It also contributes to irritability.
According to NSF, one reason for this lack of sleep is the shift of their waking hours to later in the day. Moving from childhood to adulthood, they begin to stay up later in the evening. Along with this, after school jobs and extracurricular activities often extend their waking time. While 50-60 years ago, school usually started about 9 AM, most schools now start 7:00 to 7:30. The effect is to squeeze teens’ sleeping time at both ends. This has led to many proposals to start school later, such as by the Fairfax County School Board, based on recommendations by the Children’s National Medical Center and responding to pressure from parents.
Not only teens, but adults are affected by sleep deprivation. Many young and middle-aged adults work long hours, or multiple jobs, or cap their workday with activities.
One reason we need so much sleep is regular cyber maintenance of our central nervous system. While we rest, our brains go though several cycles to reset processes, sort out information from the day, manage memory systems, and repair damage to nervous tissues. At the same time, other tissues of the body are repairing and rebuilding. On the average, we go through one complete rotation of cycles in about three hours. Two of these rotations take about six hours or more. Each rotation ends with the Rapid Eye Movement (REM) cycle. This is why we dream just before waking up.
The number one culprit in sleep deprivation is going to bed too late for the time we have to get up. In other words, we are robbing ourselves of sleep. There are a number of factors leading to this. One is modern lighting. Beginning with kerosene and gas lamps, indoor lighting became more affordable. This continued through incandescent bulbs and fluorescent lights through LEDs, making it less expensive to stay up late.
Another factor is shift work. Work scheduled during daylight hours is more natural, in line with our bodies’ rhythms. Working until late at night makes it hard to get up at sunrise (unless it is winter in the northern latitudes). The problem here is daylight disturbing the later stages of sleep.
But it is not only work and activities depriving modern people of sleep. Electronic devices play a major role. For some, the job continues long after they leave the office with text messages, emails, and forwarded business calls. Add to that entertainment and social media.
Then when we are asleep, it is not under ideal conditions, with lights on cell phones, digital clocks, monitors, etc. tricking our pituitary glands.
Tips for Getting Enough Sleep
Several sources have advice for how to get enough sleep. No two lists are exactly alike, but a few key sources are the National Heart, Lung, and Blood Institute of the National Institutes of Health, the Office of Disease Prevention and Health Promotion of the U.S. Department of Health and Human Services, the Centers for Disease Control and Prevention, and the Mayo Clinic.
Our bodies, as well as those of animals, have circadian rhythms that control daily cycles of activity. This includes when we sleep and when we are awake. This is the cause of jet lag, leaving the daily cycles of one time zone and resetting them in another. The next time zone – only an hour off – is not too bad, but across the continent or the ocean can leave us feeling “out of sync” for a day or two.
We sleep best when we do it on a regular schedule. This is not necessarily down-to-the-minute, but going to bed within the same two-hour period and getting up within the same half-hour period each day helps most people to set their cycles. This works best when we are not too far off on weekends and holidays. The cause of “Monday morning blues” is usually messed-up weekend sleeping schedules. Try to limit staying up too long to only one weekend night.
Get ready for sleep
This is not the same as getting ready for bed, although that is a part of this. Wind down your activities about an hour before bedtime. This works best if certain activities – for instance, listening to soft music or light reading – are scheduled for this time. As a ritual, it tells your body it’s time to sleep.
Not too full, not too empty
Avoid heavy eating within three hours before going to bed. Your digestion could keep you awake, especially if lying down triggers acid reflux. Also avoid caffeine and nicotine three-to-four hours before sleep, even more if you can. Nothing like an upper when you’re trying to get down. And alcohol is not good too close to bedtime. It may seem to relax, but it interferes with sleep cycles.
Control the atmosphere
We sleep better when the room is cool enough – not too hot – and quiet. Lower light levels before bed and darkness when in bed help us sleep. You may have to turn the digital clock so it does not face you in bed.
Physical activity and time outdoors during daylight help us set our body clocks. The physical activity helps our circulation, pulling enough oxygen into the body to help with rebuilding during sleep.
We all have to deal with stress in daily life. The key is how we handle it. Controlling our response to stress affects our entire body. For instance, adrenal glands react to heavy stress by releasing adrenaline, which make the body tense. Part of this is psychological, how we handle stress mentally. If we can’t handle the stress, we may need counseling or other help. Sometimes we can also control the cause of the stress.
The Role of the Mattress and Pillow
in Getting Enough Sleep
Your mattress may be a contributing factor to not getting enough sleep or oversleeping because of poor sleep. Two mattress culprits are poor support and pressure. The mattress has to preserve proper spinal posture. At the same time, it has to cushion vulnerable parts of the body in a way that relieves pressure.
Innerspring mattresses depend on pressure to support you, and this puts pressure on large joints, such as hips, shoulders and knees. Making the springs lighter to reduce pressure increases the chance of loss of support, as coils under heavier parts of the body fail.
Pressure is reduced by making the mattress more conforming to the shape of the body. The least conforming innersprings are continuous coils. These are also the most durable type of innerspring (lasting over 20 years), and this fact coupled with the lower cost persuades many consumers to buy Serta’s continuous coil models. This may be acceptable to back sleepers, but not to side sleepers.
The best way to relieve pressure on a continuous coil mattress is with a memory foam topper, such as the Snuggle-Pedic Reversible Memory Foam Topper. This 2” topper has two layers, with 4-lb. memory foam on one side and 5-lb. on the other. Latex foam toppers are another alternative. The basic difference is that latex itself has pressure.
If one is looking for pressure relief in an innerspring mattress, pocket coils are the best choice. The individually wrapped coils respond independently, yielding to larger parts while still supporting the smaller areas, such as the lower back. But these springs, like latex, still apply pressure.
Padding is needed to smooth out the feel of the individual springs in pocket coils, usually foam of some type built into the mattress above the coils. The best is memory foam, followed by latex, then polyurethane foam. If the mattress is not too high, a memory foam topper, such as the one described above, may be added.
All-foam mattresses are the best for pressure relief. However, many foam mattresses are subject to sagging when the foam no longer springs back from compression. The best foam mattresses for pressure relief are memory foam mattresses. Memory foam is made for pressure relief. It is the best mattress material for back pain.
What works for one person may not work for another. Find the mattress that helps you to sleep better.