Many of us do not think about sleep much – it is a routine occurrence that we often bend to meet our needs from day to day.

But how much sleep do we really need? When does a lack of sleep begin to interfere with our wellbeing? What constitutes a sleep disorder or insomnia? How can we enhance our sleep to ensure we are well rested for every new day?

di-ve.com spoke to Dr Mark Xuereb to answer these questions.

Sleeping is extremely important for many reasons. People who sleep less have an increased risk of heart attack, high blood pressure, diabetes, obesity and being overweight. In conjunction with other maladies, it can aggravate symptoms. For instance, people who suffer from depression can become manic if they lose sleep.

What happens when we sleep? For most of us, the only time we switch off is when we are asleep. In our state of unconsciousness, we are blissfully unaware of what is going on around us.

Sleep has two basic stages. The rapid eye movement (REM) stage comes and goes during the night and comprises around one-fifth of a night’s sleep. In REM, the brain is very active and the eyes move very quickly from side to side, though the body’s muscles are very relaxed. This is the stage in which people dream.

Non-REM accounts for 80% of a night’s sleep, and in this stage, the brain is relatively quiet while the body moves around. This stage is important because hormones are released into the bloodstream and the body goes into repair mode, as Dr Xuereb describes it. Non-REM represents dreamless sleep, and this stage is divided into three sub-stages: pre-sleep, light sleep and slow wave sleep.

In pre-sleep, the muscles relax, the heart rate decelerates and body temperature drops.

During light sleep, a person could wake up easily without feeling confused or disoriented, for instance, during a short nap.

In slow wave sleep, blood pressure drops and it is harder to wake up. A person in this stage who is awoken abruptly would feel very confused and disoriented. This is the stage in which some people talk or sleepwalk.

We usually fluctuate between REM and non-REM sleep cycles about five times a night and we generally tend to dream more towards the morning hours. In a normal night, we wake up once or twice every two hours or so, but we are often not aware of these mini wakes – often, we will only remember them if we are feeling particularly anxious or a sound in the vicinity distracts us.

Knowing the normal physiology of sleep often reassures patients that what they are going through are normal sleep processes. In fact, many people who are concerned about potentially having sleep ailments are actually prone only to what are considered as natural sleep mechanisms.

It is normal to experience problems sleeping properly from time to time, and it is often short-lived. Dr Xuereb points out that it is worth considering what is going on in other aspects of our life. If, for instance, a person is between jobs, stressed out by assignments or exams, or moving house, losing sleep is an inevitable reaction to the unsettled moment they are going through. When we are feeling particularly anxious or stressed out, we tend to dream more.

Some of us are quick to seek out a solution or over-the-counter remedy, but Dr Xuereb warns that these have their own side effects and dependency problems. For example, sleeping pills, which should always be administered by a medical professional, can be addictive and may, with extensive use, slow down the brain, lower intelligence, and hinder performance, learning, memory recall and memory processing.

One thing that many people struggle with is understanding how much sleep we need. According to Dr Xuereb, this mostly depends on age. Babies under the age of two sleep 17 hours a day and for them, this is normal. Children are advised to sleep around nine to 10 hours a night, while adults are recommended about eight hours a night. Older people need around eight hours as well, but they often have only one period of deep (non-REM) sleep per night in the first three to four hours of the night. In old age, we tend to dream less, Dr Xuereb says.

But these well-known numbers often seem unrealistic. In practice, people are different and their needs vary. Some get by just fine on three hours of sleep a night and wake up feeling fresh. For instance, as we grow older, we tend to sleep less, according to Dr Xuereb.

So how can we tell whether we are sleeping enough? If we wake up feeling refreshed, focused, and with a clear mind and good concentration, we are on the right track. It is not so much about how much we sleep, but more about the quality of our sleep and specific sleep patterns, and these are very variable, says Dr Xuereb.

The benchmark is whether we manage to function once we are awake. Though poor sleep can affect our demeanour the following day, the occasional night without sleep will not affect us long-term. For those who fear they may be suffering from insomnia, they should ask themselves whether they are truly experiencing the symptoms – chronic lack of concentration, fatigue, feeling tired all the time, possibly also accompanied by depression.

In many cases, we may unknowingly be making it more difficult for ourselves to sleep well. Several everyday habits can hinder sleep: a television or radio in the bedroom, an uncomfortable bed, a bedroom that is too hot or too cold, napping for too long (more than an hour), not exercising enough, exercising right before going to bed, eating late, going to bed hungry, consuming stimulants (caffeine, nicotine, alcohol), illness or pain, emotional problems, physical problems (related to breathing, heartburn, the bowels), medication being taken…
The list goes on and on.

Fortunately, says Dr Xuereb, there are number of simple things we can do:

• Read before going to sleep or listen to quiet music, but be sure to switch it off before turning in for the night.

• Try aromatherapy as a way of winding down before going to bed.

• Do more exercise to improve your health in general; it will eventually improve your sleep.

• Replace your mattress every 10 years to ensure it does not lose its level of comfort and support.

• If you have concerns that are keeping you awake, write your worries down before going to bed and let them go for the night; you can address them in the morning. If this does not work, get out of bed and do something until your mind starts to relax and you feel the need to rest.

• Avoid drinking tea or coffee in the evening and replace them with milky or herbal drinks that act as relaxants and reduce acid levels in the stomach, leading to better sleep.

• Try to relax your body muscles, working your way up from your feet to your face.

It is important to develop good sleep hygiene, says Dr Xuereb. Do your best to strengthen the link between your bed and sleep, for instance, meaning that you should only lie in bed when you want to sleep. Studying, doing work, or watching TV in bed can weaken your association with bed and sleep, and that can introduce worry into the space that should exclusively be dedicated to resting. It might also help to go to bed later, because the longer you stay in bed feeling restless, the more likely you are to spend time tossing and turning.

According to Dr Xuereb, trying to find a quick fix is a waste of time. In cases of sleep problems that affect a person’s day-to-day life in ways that make it hard to function normally, therapy is a more effective solution than medication.

Making changes to the environment in which you sleep and ensuring that your habits are conducive to sleeping restfully can ensure that you will wake up fresh every day. Ask yourself whether you are sleeping enough and well enough, suggests Dr Xuereb, and if you are unsure, consult sources like the National Sleep Foundation and Sleep Council websites. Consult a therapist if you feel that the problem may be coming from another aspect of your life.

In short, sleeping well may require small changes in your lifestyle, but they can be well worth the effort. After all, we all deserve a good night’s sleep.

Dr Mark Xuereb has qualifications in psychiatry, emergency medicine and family medicine. He is a university lecturer and has a special interest in sports medicine and crisis management.