Some use sleep deprivation to break you, Ray Romano tells. You could as well say, "Sleep deprivation makes many dreams fade." Chronic insomnia is most often defined as difficulty falling or staying asleep or having non-restorative sleep on most nights for at least a month.
Tackling sleep deprivation may well be in your interest. A large part of the population in Western countries suffer from chronic sleeplessness and other sleep disturbances. In the USA, about 25 percent of the workers suffer from chronic insomnia, a ccording to a nationwide survey - Workplace sleepiness costs $63 billion a year in lost productivity, and insomnia is responsible for 252 million lost days of productivity each year. When this is found out now, the focus should be on finding ways to address the problem, says Professor Ronald C. Kessler of Harvard Medical School. About one in five people with insomnia receive drug or behavioral treatments 
From this it stands out that troubled sleep is a major problem in the US. Nearly a quarter of adults are unhappy with their sleep patterns, while up to 10 percent suffer from full-fledged insomnia. And insomnia has long-term consequences, says Dr. Charles Morin. A 2002 report suggests that insomniacs are more than twice as likely to have congestive heart failure than individuals without the disorder. Besides, long-term studies suggest insomnia may be a risk factor for numerous psychological disorders. It is a pressing public health problem.
Despite that, much insomnia goes undiagnosed and untreated, even though treatment may be possible. Dr. Morin says that people should not assume sleep problems will take care of themselves, and that health care providers should pay close attention to the various treatment options. 
Then what about the guru Yogananda, who passed away in 1952? He slept very little for many years, if he slept at all, and died of a heart attack when he was 59. Before he passed away, he taught followers they should sleep less than average . . .
"Life is something that happens when you can't get to sleep," says Fran Lebowitz. Add "-as long as it lasts to that."
"You want to know your requirements, not those of the average Joe . . . Some people . . . genuinely need nine or ten hours of sleep a night to function well . . . sleeping nine to ten hours a night is not in itself a sign of ill health or laziness," assesses Dr Lawrence Epstein. He goes on to show many signs of getting too little and enough sleep. Being drowsy at day and nodding when watching TV, are two signs of not getting enough sleep, and feeling fully rested is a sign of sleeping well enough. He lists more such signs too. (Epstein with Mardon 2007:28-30, passim).
Here is another good reason for getting a proper amount of sleep: It 'cuts stroke risk'. A computerised analysis of health, lifestyle and other factors among 288,888 adults who took part in a survey from 2004 to 2013, brought to light that those who got 7 to 8 hours of sleep a night were 25% less likely to get a stroke. Those who slept for more than 8 hours a night were 146% more likely to get a stroke, and those who slept less than 7 hours a night were 22% more likely to get a stroke. Besides, fit exercise, including walking, swimming and cycling three to six times a week lessened the stroke risk too. These results, presented at the American Stroke Association's International Stroke Conference (19 February 2016), echo previous research where for example poor sleep quality among older people goes along with a higher risk of stroke.
Sleeping very long or very short may be symptoms of one or more factors that bring about stroke, and not direct causes of stroke. Still, one should pay heed:
They say sleeping short or long increases the risk of stroke, but a more fit way of telling it may be, "Sleeping long and short go together (co-variate) with an increased risk of stroke." What are causes and what are symptoms may not be easy to sort out, but a good doctor seeks to, to avoid superficial dealings. Sleep disturbances are very common today, co-vary with stress, but are often treated superficially, without seeking to find or remedy possible, underlying causes. And some deeper causes are related to lifestyles. For example, stress builds up diseases, including sleep disturbances and heart disease, and stress may be alleviated or handled by such as meditation. Statistics have brought about ample documentation of it. [◦The Mayo Clinic on coping with stress and meditation]
Average statistics may offer some initial help in sorting out things and getting aware of a problem, but "As you cry in the wood, so will your echo be". It means "coarse divisions into groups give coarse research answers". For example, there is a large difference between sleeping one hour longer than the average, and seven hours longer. One or two hours more sleep a night more could be helpful to lots of persons, whereas seven hours more might be a sign of some disturbande, even illness. Similarly, just how many hours one sleeps short over a longer period counts. It is a "graded affair", so we had better allow for nuances. When research is designed to be less coarse than "sleeping short", sleeping long", results may be more nuanced and work better for it.
Solid statistics can be helpful in singling out overt risk factors. In this case they are divided into "much", "average" and "little" sleep. As suggested above, the solution to more relevant findings is to grade "much" and "little" further. That is some help, but still not ideal help. Why? Many causes of strokes may not stand out from averages-based statistics, for people are individual (not average). It is good to take individual causes into account too, even though average-based statistics hardly find such ones unless they are shared by many. Besides, our organisms differ a lot too, down to the size and performance of the internal organs, Dr Gordon Allport shows in Personality (195...)
Average statistics of sorted groups still needs to allow for some leeway and individual assessments. It means you may try to find out how much sleep you need "all by yourself", with the help of research findings if you get to good sources of it. Go to a qualified professional if you can. If not, Dr Epstein's book is good for self-help diagnosis. However, sleep medication to relieve symptoms might be a two-edged sword.
As you don't want to become dependent on pain-killer drugs and antidepressiva because they are no good overall solutions, you take a look at alternative treatments, such as acupuncture, ayurveda, chinese herbal medicine, Western herbal medicine, homeopathy, yoga and meditation to get better from stress, which is a frequent cause of troubled sleep for all too many. If there is some leeway for you, try some complementary or alternative treatment first, and maybe that "will do the trick". In that case you find something or someone that helps. You should might also check whether you lifestyle sustains health by quality living, or disease by stress and cramped conditions, and seek help wisely.
It means: When it comes to treatments and orientations, opinions vary, also among medical professionals. There could well be alternatives to drugging yourself to sleep.
Not all are asleep who have their eyes shut. (Proverb)
The Americanised guru Yogananda (1893-1952) talked for sleeping less, being "electrified" through kriya yoga. The core of it is to breathe gently in an ujjayi way. Some prefer to keep they eyes closed while meditating.
If kriya yoga does not do the trick, believing in Yogananda's pet idea that "five hours of sleep is enough" and so on, could cause sleep deprivation to your loss. Clumsiness is one effect.
Yogananda, himself a very light sleeper, if a sleeper at all during his last few years, died of a heart stroke at 59. That is what the doctor who examined him at the time stated. That Yogananda's fellowship SRF calles it his mahasamadhi, does not alter a doctor's medical conclusion.
We can learn from the life of a person too, and not just what he says.
The lot of Frankenstein's monster
The monster in Mary Shelley's debut novel Frankenstein from 1818, was vivified by electricity. Frankenstein's monster is often portrayed as a sleepy, freaky, slow, clumsy fellow, a bit like a sleep-deprived goof - Enough sound sleep bulwarks against trudging along such a road in life.
If Tom, Dick and Harry cut down on sleep because they have been inspired by yogi tales or tales of hibernating bears in caves, they might benefit from cold water thrown on them instead of getting awfully sleepy and manipulated in a state of serious sleep deprivation.
There is a study of kriya yoga by Das and Gastaut (1955), where one kriya yoga performer outdid others in "sitting like a log". He was not representative of the majority of the yogis in the study. Think of it: If one out of four hundred kriya yogis says he can do without much sleep and so can you, reserve your judgement about the latter part at least. People are different, with widely differing needs.
Kriya yoga is at heart the gentle pranayama method that is otherwise known as ujjayi in hatha yoga. The additions that make it called kriya yoga by some, include postures and other parts of hatha yoga. A variant of ujjayi is described in the Hatha Yoga Pradipika (2:51-54). That text is from the 1300s.
You are served by less hype than the guru Yogananda went for. Ask for evidence, verfied too. Ask for sound research findings, and reserve judgement until you have got a fair amount of good, solid facts. That could help you steer along if you first sort out where your feet are standing and go on from there. One should seek not to overstretch - not to practise what you are not mature or ready for. Such helpful hints could give you the upper hand when it comes to your actual practice.
Below are a fair amount of research findings about sleep and sleep deprivation. There is much to get proficient in.
When you become experienced in meditation, able to go deep into superconsciousness, five hours of sleep are enough. - Yogananda, Ak 20
I think six or seven hours of sleep is enough. After that you don't actually sleep; you drug the body. [Yogananda, in Dr 185]
True or false? See what sleep research has come up with and adjust well, and thereby draw benefits. Ferret out the facts first, and if you wish, add Yogananda's prayer-demand, "Save Me from Wrong Beliefs," if that should be wanted too [Wfe No 150]. For one thing is what Yogananda taught; another thing is what is fit. What SRF's Yogananda teaches about sleep could derange less than half the followers. Guru followers are told by a society's "Beloved Leader, whose guidelines we don't find faults with", to cut down sleep to seven, six, or five hours a night, depending on what quotations are resorted to, ignoring that many persons need far more sleep to function well. Being a sectarian guru follower, on the other hand, how fallen is that?
As for cults and sects and whatever they call themselves, some who find it fit to break down the resistance of others, may deprive them of sleep and go on to indoctrinate them more easily. There is fair literature that goes into such methods as hard cults thrive on: propaganda, manipulation, mind conditioning, thought reform, brain-washing - name are many, and the degrees of severity are many too. Propaganda may be the inviting first step. Autobiography of a Yogi contains much tall kriya yoga propaganda in the form of unverified, fantastic claims, while telling nothing of the many backsides to learning it from Yogananda's fellowship, SRF - to learn it there you have to become a "New Age bondsman" by an oath without regret buttons. It goes against many human rights, for sure. [Literature on "mind-battering"].
Breaking down the selfhood of a glowing follower is feasible, but not much of a good accomplishment. It is fit to seek to found your rhythms of living on facts that rank higher than what is childishly "doctrinated" in sects as "infallible".
Just be aware of cult signs along the road and don't ignore them.
"How much sleep do I need - and what may happen if I don't get enough?" is a legitimate double question. 7,5 to 8 hours a night is the average. Many need more and others much more. If we get too little sleep, we may get awfully tired and make stupid mistakes and endanger ourselves and others thereby. And in the longer run, health may suffer.
"Can I really get on by four or five hours a night?" The short answer is: No, in the long run you probably can't. But all are not alike.
"A few people need a little (four to six hours), a few people need a lot (nine to ten hours), and most are in the middle (seven or eight hours). Most sleep specialists believe that the overwhelming majority of people need at least seven and a half hours of sleep to function at their best. That's a good goal for the average person." - Lawrence Epstein with Steven Mardon, [Hgs 27-28]
Now it would be good to search for the key causes of your lack of sleep. Could it be deficient sleep guidelines by someone you trust? When that happens, it is better that the ill-founded trust goes than your fair health.
From here I go into more sides to averaged sleep lengths for different sorts of folks, various effects of sleep reduction, sleep deprivation, and what is called normal sleep:
Sleep research, initially
Sleep length varies among people
Some people naturally sleep for eight and nine hours a night, and some even longer. And the effects of sleep reduction can rebound. See what experts maintain below, and bear in mind that one has to make allowances for the fact that that some diseases, like allergies, simply call for more than an average length of sleep too. There is much research to draw on to suggest how necessary sleep is for health, well-being and life itself.
Help yourself at night
You can help yourself get a truly good night's sleep, says Lawrence J. Epstein in A Good Night's Sleep. Sleep is basic, and most people can get better sleep. I appears that in 2005, about 75 percent of the American population had at least one symptom of a sleep problem. Moreover, the partner of someone with a sleep disorder is often as disrupted as the one with the disorder - if they sleep in the same bed, for example. Experts think most people need 7,5 to 8 hours sleep to function at their best. [Hgs 3-5]
From sleeping too little
Sleep experts tell from how several long-term studies reveal that if you sleep less than five hours a night, you're more at risk of developing depression, heart disease, stroke and type 2 diabetes. A recent major study suggested that women who sleep for six hours or less each night were 62 percent more likely to develop breast cancer than those who sleep seven hours. Lack of sleep has been shown to affect hormones and metabolism, making overeating and weight gain more likely. Moreover, lack of sleep can lower your immunity, affect your mood, leading to relationship problems. Your judgment may be impaired. And overall, evidence suggests that people who sleep less than five hours at night don't live as long as those who sleep seven to eight hours. [Tdt 13, 14, 19].
Assess your own sleep need and whether you are sleep-deprived
How much sleep do you need? Wendy Green thinks the answer can be found by "listening to your own body. If you're able to fall asleep fairly quickly at night when tired, enjoy largely unbroken sleep and awaken feeling refreshed, then you're probably getting enough sleep - regardless of how much that is." Sleep expert Neil Stanley says, "What is important is that you get the right amount of sleep for you. Simply, if you feel awake and function at a high level during the day, you are probably getting enough sleep, but if on six hours sleep you feel sleepy the next day, then it's not enough for you." [Tdt 20]
"Take a minute to think about how much sleep is not enough for you. The key here is daytime drowsiness," says Epstein. "Along with feeling drowsy in the daytime, you're probably sleep deprived if you (a) struggle to get out of bed; (b) are frequently irritable; (c) have difficulty concentrating; or (d) nod off or come close to nodding off after lunch or dinner, at the movies, watching television, or while driving." [Hsg 28-29]
Wendy Green counsels that you answer these questions: (1) Do you rely on an alarm clock to wake you up? (2) Do you feel sleep during the day? (3) Do you doze during the day, whenever you have the opportunity? If you answered 'yes' to any of these three questions, it is likely you are sleep-deprived. To find out why it is so, identify the root causes of your sleep problems, she says [Tdt 21]. Learning about normal sleep will allow you to recognize if what you are experiencing is a genuine problem. Further, seeking to address the source of the sleep problem should improve your sleep and your daytime energy and alertness, says Epstein. [Hgs 9]
Varying lengths of sleep, and REM sleep
Jim Horne goes on to tell: "There will be some who sleep longer or shorter than the average, and I am excluding those who have insomnia. For adults aged between 20 and 70 years, the average [which is thirty-four percent] sleep is between 7 and 8 hours a night" [Sjs 172] - and around twenty minutes longer for women than men. Around the seven-eight hours average "is the typical bell-shaped 'normal distribution', with decreasing numbers sleeping longer and shorter than the average." [Sjs 172-73] Accordingly, around 24 percent sleep for 8-9 hours a night, and about 12 percent sleep for 9-10 hours a night. And ca. 5 percent sleep for 10-11 hours a night. One or two percent sleep over 11 hours. [From figure 15, in Horne 2006, p 172]
The first five hours of sleep seem to be of the same quality for five- and nine-hour sleepers alike, in terms of how light or deep the sleep is, and rapid eye movements (REM). Both types have similar amounts of deep sleep and REM sleep. [Sjs 173] Also, about every ninety minutes, a sleeper enters REM sleep, going through several stages of sleep throughout the night, alternating between REM and non-REM sleep. In normal young adults, there are usually for or five alternating non-REM and REM periods. Most deep sleep occurs in the first half of the night, and as the night progresses, periods of REM sleep get longer. Later in life there is less deep sleep, says Epstein. [Hgs 18]
Cutting down on sleep - and mania
From long to short sleepers
Extremely short sleepers and extremely long sleepers are very rare. Natural sleep of these sorts is termed healthy if the sleepers feel quite alert and are not dozing off during the waking day. Healthy short and long sleepers do not differ much by way of intellect and IQ. However, there is a tendency for short sleepers to be more 'enthusiastic' people, and very short sleepers may tend toward mild mania. Very short sleepers "may have a somewhat shorter life expectancy." [Sjs 174, 175]
Great short sleepers are found
As for famous leaders and notables who have been able to survive on little sleep, like Alexander the Great, Napoleon Bonaparte, and Thomas Edison, they "all were somewhat hypomanic [having mild manias]." [Sjs 175] Further, a study of naturally short sleepers found that they had a more positive attitude to life and were more optimistic. Long sleepers, on the other hand, were more likely to be 'worriers'. For all that, the long, happy sleeper is to be reckoned with too. And true happiness has no mania and nothing faked in it, I would add. [Sjs 174]
Sleep reduction is possible, but count the possible, accumulating cost
It may be feasible for some to cut down on sleep to the degree that Yogananda tells followers to. "Given a few weeks of gradual sleep reduction, people may well be able to adapt to taking less sleep, without increasing their day-time sleepiness. I am not advocating that we do so," says Horne, and speaks of the effects. "Restriction to six hours of sleep is just about the limit for most people," he goes on to say on the basis of studies on sleep reduction. However, there was a snag to it: the extra wakefulness that resulted from cutting down on sleep, was used by the participants in the study just to waste time. [Sjs 180-82] And lack of sleep is directly linked to poor health, including heart disease, diabetes, and obesity. Even a few nights of bad sleep can be detrimental. [Hgs 5]
Sleep reduction is possible within some reasonable bounds, but hardly recommendable, one may add. "Are we chronically sleep deprived?" asks Horne before commenting: "Increasingly, it is being claimed that seven to seven and a half hours of sleep per night, typical for many healthy adults, is insufficient, and that chronic sleep debt is becoming endemic in western populations. Seemingly, many of us are largely unaware of this apparent chronic sleepiness, and to avoid this state of affairs we should be taking up to nine hours of daily sleep." However, there is a great chance that "much of this sleepiness is more imagined than real". Horne brings up his arguments and the studies he bases them on, in the following twenty pages. [Sjs 184, 184-205]
Cumulative sleep debt
Partial sleep deprivation - when you get some sleep, but not 100 percent of what you need - is said to bring on what is called sleep debt. Concerning cumulative sleep debt, Lawrence J. Epstein says, "When you fail to get eight hours of sleep, you start to accumulate a sleep debt . . . The greater your sleep debt over a few days, the stronger the drive for sleep." In the quote, "eight hours" stands for the certain amount of sleep the body needs to function at its best, and that could be more or less than eight hours. [Hgs 24]
Epstein writes that by sleeping more than usual we can repay a sleep depth. In such cases we add an extra hour to the hours of sleep you really need for several days, and then we can return to getting the sleep the organism needs without the added hour. And "if you've accumulated hundreds or thousands of hours of sleep debt" through bad sleep habits by heeding insensible directives and rules, "a few weeks of getting the sleep you need, plus a bit more, should clear the slate," writes Epstein. [Hgs 36-37]
Estimated costs of sleep deprivation and sleep disorders
Studies have shown that performance on tests of alertness and thinking continues to get worse the longer the sleep deprivation lasts. So we do not adapt to sleep deprivation. Further, sleep deprivation and sleep disorders are estimated to cost Americans over $100 billion [100 000 000 dollars] annually. Sleep problems affect moods, mental alertness, work performance, energy level, and the sex life of about a quarter of partnered adults, so there are many good reasons to wake up to the importance of sleep. [Hgs 6-7]
A repeat: We are not alike. By comparison, a horse needs 3 hours, a cow needs 4 hours, a rabbit 8 hours, a cat 12,5 hours, and a bat needs 19 hours. [Hgs 30]
Larks and owls among us
Some are inborn early risers, termed larks, and some are late risers, called owls. Owls go late to bed and sleep late. Standard sleepers are in between the larks and the owls in that their sleep/wake rhythm pushes them to sleep from about 10:30 or 11:30 PM to 6:30 or 7:30 AM. [Hgs 30-31]
As we age, we have tendency to go to sleep earlier, typically by about an hour. [Hgs 31]
On sleep, sleep curtailment, sleep deprivation, and sleep recovery
Sleep's brain activation
J. Allan Hobson, a man who needed eight to ten hours of sleep and still did not feel completely refreshed when writing Dreaming: A Very Short Introduction [Dsi], tells of the value of sleep and of dreams too. Studies in sleep laboratories have brought such evidence that it is generally assumed that everyone dreams in sleep. Recalling the dreams is quite another matter. [Dsi 70, 10] The brain self-activates in sleep. Brain activation in sleep is essential to survival because it allows the organism to restore the effectiveness of its core regulatory systems, Hobson goes on. [Dsi 70, 76, 71]
Recovery from sleep-deprivation debated
After three or four weeks or so, sleep-deprived rats begin to die off. Some persons get psychotic through prolonged sleep deprivation. A good thing is that recovery should be complete for those who have been deprived of sleep for a week or two - when sleep finally is allowed. [Dsi 76, 72, 75].
Is really sleep recovery complete, as Hobson says? It depends. Jim Horne says in Sleepfaring that following "a night or two without sleep, or even longer ... only around a third to a half of the lost sleep seems to be reclaimed on recovery. Almost all of the deep sleep is recovered, but most of the missing light sleep seems to be gone for good." And then he adds some detail. [Sjs 178-79]
Long sleepers and short sleepers
"When long and short sleepers [referring to length of sleep and not body size] are sleep deprived for a night, long sleepers do not usually sleep for much longer than normal during the following recovery night, because this sleep seems to 'soak up' the essential parts of the lost sleep that has to be recovered, at the expense of light sleep. [Sjs 173-74]" This essential sleep is mostly deep sleep. And, to quote Epstein: "Deep sleep seems to be a time for your body to renew and repair itself." [Hgs 15] Horne: "Short sleepers, on the other hand, have to extent their recovery sleep to replenish lost deep sleep. It is as if they have no spare capacity within their normal sleep to absorb it. The average sleeper lies between these two extremes." [Sjs 174]
Hobson informs that short sleepers (four to six hours a day) are no more 'abnormal' or unusual than longer sleepers (eight to ten hours a day). But there is a caveat: Short sleepers tend toward being more 'enthusiastic' and having mild manias [Sjs 174]. Hobson mentions further that sleep curtailment compromises his ability to be attentive and to organize his own mental activity efficiently and effectively. [Dsi 70, 76, 71]
Epstein defines complete sleep deprivation as what happens as the hours of waking go beyond sixteen and seventeen hours. The immediate result is you feel tired, and then you feel exhausted. A study showed that twenty-four hours of wakefulness had the same deleterious effect on driving ability as having a blood count of .10 (one per thousand) and 'under the influence'. If complete sleep deprivation lasts longer, things go downhill, and mood swings, depressions, and increased feelings of tension are less rare. Total sleep deprivation can be dangerous and even fatal. [Hgs 32-33]
Partial sleep deprivation
Partial sleep deprivation is the type that occurs when you get some sleep, but not 100 percent of what you need – commonly what we think of as building up a sleep debt. Problems are more likely to become apparent after two or more nights of short sleep. The most obvious signs are increased irritability and sleepiness. Work performance begins to suffer, particularly on complicated tasks, and people are more likely to complain of headaches, stomach problems, and sore joints. In addition, people are at substantially higher risk of falling asleep on the job and while driving home." Short term consequences of sleep deprivation are increased accident risk, and long term consequences are increased disease risk. [Hgs 34-35]
Benefits of sleep
If, like Yogananda, you have been used to "treating sleep as a second-class citizen in your life," you may get rid of sleep debt by getting more sleep. "It will take some time to fully recover lost sleep but you will feel the effects quickly." It may be better alertness or performance, or both. It may be improved memory and creativity, and improved overall health, writes Epstein. [Hgs 37-38]
Finally we go from the little sleep to the "big sleep" (next page).