Counting Sheep: The Science and Pleasures of Sleep and Dreams. Paul Martin

scant attention paid to its preparation or enjoyment. Fortunately, Britain has since developed more enlightened (if not self-indulgent) attitudes to food, and recent decades have witnessed cooking and eating emerge as pleasurable activities in their own right. For some people in wealthy nations, cooking and eating have become more a form of entertainment than a biological function.

      Meanwhile, sleep is mired in the cultural equivalent of a 1950s British canteen meal: an inadequate and faintly unhealthy affair, indifferently concocted and consumed with more haste than enjoyment. Too many people regard sleep as the brain’s equivalent of fast food or overboiled cabbage. If gastronomy is ‘the reasoned comprehension of everything connected with the nourishment of man’, as it was originally defined, then should we not start thinking about sleep in the same way? I hope that by the end of this book you will be pondering the gourmet delights of sleeping, napping and dreaming, and starting to savour more of their lost pleasures for yourself.

PART II Insufficiencies

       2 Sleepy People

      She looked a little worn out, a little tired, but, then again, didn’t everybody? We all look a bit tired, these days, some more than others.

      William Boyd, Armadillo (1998)

      Many of us in our everyday lives are getting sleep of inadequate quantity and quality, and this is bad for our mental and physical health. Lack of sleep makes us inefficient at work, dangerous behind the wheel of a car and unattractive to be with; it lowers the quality of our lives, causes accidents and makes us more vulnerable to illness. And it is unpleasant.

      I am not referring here to the acute sleep deprivation that comes from occasionally staying up all night, although that is common enough in professions such as medicine, the military and politics. Rather, I am talking about the chronic sleep deprivation that accumulates as we continually stint ourselves of sleep, day in and day out, because of the conflicting demands of work and leisure, or because of a sleep disorder, or just because we do not think sleep is important. So, what are the reasons for believing that sleep deprivation is a real problem?

Are we sleep-deprived?

      Eight hours they give to sleep.

      Sir Thomas More, Utopia (1551)

      The evidence that chronic sleep deprivation is a common feature of contemporary life comes in several interlinked strands. We will start with perhaps the most obvious one of all: the observation that many people feel sleepy when they are awake.

      Assessing the extent of daytime tiredness in society is tricky, not least because so many people have come to regard feeling tired as normal. Nonetheless, numerous scientific studies have unearthed evidence that the problem is real and widespread. For example, a 2001 poll of Americans’ sleeping habits found that 22 per cent of adults felt so sleepy during the day that it interfered with their activities. A 1994 survey found that 5 per cent of the British population were experiencing severe daytime sleepiness, while a further 15 per cent felt moderately sleepy during the day. It also found that the people suffering from daytime sleepiness were twice as likely to have a vehicle accident.

      A similar picture has emerged from other countries. For instance, a recent study discovered that 10 per cent of middle-aged Finns were excessively tired and tended to fall asleep unintentionally during the day. Their sleepiness was statistically associated with an array of nasty things, including a heightened risk of traffic accidents, premature retirement, depression and anxiety. In Sweden, 9 per cent of adults were found to be suffering from daytime sleepiness, while a survey in Warsaw recorded that 21 per cent of adults felt moderately sleepy during the day. Australian researchers detected excessive daytime sleepiness in 11 per cent of adults. You get the picture. Not even the youngest and healthiest are immune. A French investigation of 58,000 army conscripts discovered that 5 per cent of these fit young men were affected by excessive daytime sleepiness and 14 per cent of them were sufficiently tired to sleep during the day.

      Overall, it is safe to conclude that at least one in ten adults in the general population (you, me and the people next door) are currently affected by moderate or severe daytime sleepiness. Some scientists believe the situation is much worse, with up to one in three adults suffering from significant sleepiness. A major review undertaken by the US National Commission on Sleep Disorders Research estimated that as many as 70 million Americans – more than a quarter of the population – were suffering from sleep deprivation or some form of sleep problem, at a direct cost to the national health care bill of about 16 billion dollars a year. The Commission’s report concluded that:

      A convincing body of scientific evidence and witness testimony indicates that many Americans are severely sleep-deprived and, therefore, dangerously sleepy during the day … By any measuring stick, the deaths, illness, and damage due to sleep deprivation and sleep disorders represents a substantial problem for American society.

      The problem appears to have deepened over time. Objective evidence about historical changes in sleepiness is hard to find, but there is some. A standard psychological test of personality, which has been regularly administered to large numbers of Americans since the 1930s, revealed that the proportion of men who felt tired during the day was significantly higher in the 1980s than it had been in the 1930s. And the average amount of sleep American students get has fallen by more than one hour over the past three decades. We seem to be a generally wearier bunch than our forebears.

      Tired people are certainly common enough in the doctor’s waiting room. Physicians frequently encounter patients complaining of feeling tired all the time. The condition even has its own acronym, TATT. Of course not everyone who feels tired all the time is suffering from a lack of sleep. Chronic fatigue can result from anaemia, diabetes, cancer, depression and a whole host of other medical disorders. The distressing condition known as chronic fatigue syndrome (CFS), also referred to as myalgic encephalomyelitis (ME), is characterised by debilitating fatigue, pain in the muscles and joints, impairments in thinking and a general, horrible malaise. CFS is a distinct medical condition that cannot be attributed simply to lack of sleep. The origins of CFS remain controversial, but current theories focus on a combination of malfunctioning immune reactions and psychological factors.

      CFS and other medical conditions undoubtedly account for some of the tiredness in society, but not much. The fact is that most people who feel tired during the day are just that – tired. They are tired because they have not been getting enough sleep. This explanation is so simple and so blindingly obvious that it is frequently overlooked.

      Ordinary, everyday tiredness does not always require a medical explanation, but one is often sought nonetheless. ‘Exhaustion’ has become a voguish affliction of actors, pop stars and other celebrities. From time to time, a distraught and haggard celeb will flee to a clinic feeling, well, exhausted. The clinic duly subjects them to a battery of medical tests to establish whether they have diabetes, anaemia, ME or a thyroid disorder, while the media throb with stories about personal relationship problems, nervous breakdowns, exotic diets, exotic drugs, professional insecurities and emotional crises – just about everything, in fact, apart from plain tiredness. But given the long hours they are sometimes expected to work, plus the jet lag-inducing international travelling, it would be surprising if our stars of stage and screen did not occasionally feel very tired.

      Another reason for believing that sleep deprivation is a common problem is that many of us get less sleep than we want or need, and considerably less than the proverbial eight hours we all supposedly aspire to. The evidence on this point is clear. For example, research found that in the 1990s young American adults were sleeping for an average of 7.3 hours a night. However, even this modest figure was inflated by weekend lie-ins: on weekday nights, Americans slept for an average of only 6.7 hours. A more recent study, which assessed the sleep patterns of