How to improve sleep quality: an expert guide
Dr. Jason Ellis is a Professor of Sleep Science and Director of the Northumbria Sleep Research Laboratory. He is a qualified Somnologist, expert in Behavioural Sleep Medicine, a Practising Health Psychologist, and author of The Insomnia Cure.
Why do we sleep?
While sleeping may seem like a passive activity, it was only in the 1950s that we started to understand that there is in fact a lot more going on beneath the surface. Sleep really is a reflection of daytime activity where you are walking, talking, and using up lots of energy. At nighttime, you actually use about the same amount of energy as you do during the day but it’s diverted internally.
I’m often asked what happens if we don’t get enough sleep? Without a sufficient amount of sleep, and certainly enough deep and REM sleep, we start to see a detrimental impact on our physical, mental and emotional health, both in the short and long term.
What are the different stages of sleep?
There are two main stages of sleep. Firstly, REM (or rapid eye movement) sleep, which involves dreaming. When we look at people's brains during this stage, it tends to look almost like they're awake. It’s during this phase of dreaming, that long-term memory consolidation and emotional regulation occur. For example, if you've had a bad day, if you're stressed, or you've seen something traumatic, it’s during REM sleep that your brain attempts to organise, work through and make sense of those experiences.
The other main stage is called non-REM. Taking up 75% of the night, non-REM sleep is made up of four semi-distinct stages. Stage one is where your brain activity starts to slow down and should only take about 5-10 minutes. Stage two takes about 50% of your whole sleep and in effect, acts as a filing system where your brain decides what is important to remember (and consequently turned into long-term memory), and what is less important (and to be forgotten). It also acts as a way to protect deep sleep and REM in the face of noise or pain.
Finally, we've got stages three and four which are all about restoration and repair. The main area of focus here is the endocrine system, which uses hormones to regulate your body’s vital internal processes such as energy, reproduction, stress management, growth and development. Immune system functioning is also closely tied to deep sleep More recently, it was discovered that certain toxins, such as beta-amyloid (a protein associated with Alzheimer’s disease) are also removed from the brain during deep sleep.
How much sleep do we actually need?
Every individual has different sleep requirements, since we are all unique beings all leading drastically different lives. While there is no definitive number, there is a general optimal range for adults which is around seven to nine hours per night, plus or minus an hour. Below six or above ten hours tends to be a sign of an abnormal sleeping pattern.
Really, the key point is how do you feel in the morning? About half an hour after you've woken up you shouldn’t feel tired enough that you want to go back to bed. If you do, it could be a sign that there is an issue with either the quality or timing of your sleep.
What affects sleep quality?
There are a few factors to consider when it comes to sleep quality: how long it takes you to fall asleep, how often you wake at night, the times of night you’re asleep for and how long you sleep for overall. If you’re alert during the day and fall asleep quickly at night—that’s a good sign. If your sleep is unbroken, this also generally indicates you are experiencing good quality sleep. Lastly, if your sleep takes place somewhere between 9pm and 8am, and overall you sleep between six and nine hours, you’re in the optimal sleep zone. All these factors together contribute to what we would call quality sleep.
How can you measure sleep quality?
We’ve talked about sleep stages, where stage one is falling asleep, stage two is light sleep and stages three and four are a deep form of restorative rest. Throughout the night, you progress through stages one to four and then you enter REM sleep. This is known as your sleep cycle and each iteration should take 90-100 minutes before it repeats itself. Over the course of the night, you'll get most of the slow wave deep sleep in the first half of the night. In the second part of the night, you get a lot more REM sleep. This makes sense from a biological perspective—it's important to keep the human body alive and efficiently working, and that's why we capitalise on those early hours, to get more slow wave, deep sleep. In the latter part of the night, we deal with emotions and memory. Each sleep stage exhibits different brain wave activity and so, measuring how much of each of those stages people are getting would provide a good insight into sleep quality. But of course, it's very difficult to measure this outside of the laboratory. Therefore, we have to rely on how people actually feel about their sleep.
When we talk about how to have better sleep, it’s firstly important to establish a baseline. If you’re interested in improving sleep, whether it’s the amount you sleep or the overall quality of it, start keeping a detailed journal of your sleeping habits. Over a period of time, change different factors, such as when you go to bed and see the effect it has on how you feel in the morning until you reach a place where you see tangible improvements.
What is insomnia and how is it diagnosed?
Insomnia is the most common sleep disorder, affecting about 10-15% of the population. We would generally classify insomnia as being dissatisfied with your sleep, this dissatisfaction may include difficulties getting to sleep, staying asleep, or waking up too early in the morning. Naturally, if you don't give yourself enough time for sleep, you'll find yourself in a sleep deficit. The real problem, however, arises when the individual experiences notable daytime dysfunction or impairment. What we mean by that is that it becomes more difficult to work, manage the household and even maintain relationships. You might experience difficulties with mood stability, memory, or concentration too. These issues should persist for at least three months to get a clinical diagnosis.
The work that I do is looking at the early stages of the condition, with a view to prevent insomnia. Thus far, what we've understood is that having two weeks of sleep problems, usually in response to stress or anxiety, is quite normal. Any longer than that and it becomes abnormal: you can't elicit a stress response for very long without starting to damage the body itself. After the two week mark, an individual should be treated as quickly as possible in order to have the best chance of success.
How can you improve quality of sleep when you have insomnia?
It might sound counterintuitive, but if you start to experience insomnia, the best thing to do is nothing. There will be a tendency to compensate for the lack of sleep by napping or lying in, but these things can actually create a longer term problem. Strategies such as drinking more coffee to stay awake and drinking alcohol to get to sleep are all in fact very detrimental to the sleep cycle itself. If you avoid these strategies in those first two weeks, your body will correct itself and normal sleep should resume.
If these sleep issues persist, there are a number of alternative ways to improve sleep that may help manage the problem. For example, if you are in bed and find yourself struggling to get to sleep, get out of bed. By lying there awake for a long time, you might yourself getting frustrated, and worried—these negative emotions are then associated with the bedroom itself, making sleep even more elusive the next night. Even if you don’t struggle with insomnia, normal occurrences, such as an argument with a partner, can really affect your sleep cycle. In this instance, get out of bed and do something relaxing for half an hour. The importance of getting out of the bedroom is to avoid introducing lots of daytime behaviours into your desired sleep space. To improve sleep, you want to keep a clear line between where you associate areas of wakefulness and sleep.
Beyond the three month mark, you might want to consider therapy. Cognitive behavioural therapy for insomnia is very effective and works for about 60-70% of patients lasting for at least 10 years. The only reason we don't know it lasts longer at this point is because we haven't studied it for more than 10 years. It’s an effective treatment to provide immediate relief and also improve sleep quality in the long run.