Dossier: Strong mind

Sleep hygiene: vital for our well-being

We know how much we suffer when we haven’t slept enough. And we don’t sleep well in stressful situations either. Psychiatrist and sleep researcher Christoph Nissen explains the effect of sleep on our well-being and what we can do to sleep better.

Text: Katharina Rilling; Photo: Annie Sprat / Unsplash

Poor sleep results in a bad mood, not being able to concentrate and makes you less resilient. You are more likely to find yourself in a conflict and more prone to mistakes, your mood darkens and the day stretches out in front of you like a great yawning void. It becomes very quickly apparent: we cannot function on too little sleep. And vice versa, our sleep suffers if we feel imbalanced and stressed or facing a crisis.

And the science confirms what we know in everyday life: “Sleep and mental health are closely connected” says sleep researcher and psychiatrist Christoph Nissen, chief consultant and deputy director at the University Psychiatric Services, Bern. “We have known for a long time that many psychiatric problems such as panic attacks and depression lead to sleep disorders. More recent research has indicated that this is also the case vice versa: healthy sleep is vital for our mental health”. But how exactly does lack of sleep affect us? How can I promote healthy sleep? What might help me fall asleep? And from what point on do sleepless nights start to affect us? 

Fact 1: sleep disorders can have a huge impact on our mental well-being and vice versa.

“The odd sleepless night or period of poor sleep is part and parcel of life. It does not necessarily indicate a problem of a medical nature. It won’t help to drive yourself crazy with worry,” says the chief consultant. “Persistent and severe sleep disorders are however a large risk factor for psychiatric problems.” Someone who has three sleepless nights a week over a period of three months or more, or who can’t sleep without constantly waking up or doesn’t get enough sleep is probably suffering from the most common sleep disorder: insomnia.

Sleep disorders such as insomnia and sleep apnoea make people less risk averse, more irritable and unable to concentrate. In addition it may cause panic attacks, depression or lead to addiction and memory loss. “Psychologically healthy people who suffer from a severe and chronic sleep disorder are around twice as likely to suffer from depression five to ten years down the line.” Patients with a sleep disorder who previously suffered from depression are also more likely to suffer from it again. Clearly sleep disorders are more than a mere inconvenience and often symptomatic of a psychiatric problem as we have long suspected. They can also be triggers for such diseases. 

This is valuable knowledge for diagnostics and therapy in order to recognise, treat and prevent psychiatric diseases at an early stage. “In recent years we have discovered that sleep is an important parameter for health that requires special treatment”, says Nissen. And initial research has shown that, in addition to the more traditional treatment methods, a psychiatric disease prognosis can be improved upon through sleep training. 

“The odd sleepless night or period of poor sleep is part and parcel of life. Persistent sleep disorders are however a large risk factor for psychiatric problems.”
Sleep researcher and psychiatrist Christoph Nissen

Fact 2: we declutter our brains when we sleep 

So why does sleep help keep us healthy? “The role that sleep plays for our health still remains surprisingly unknown even though we spend around a third of our lives asleep. Something that occupies so much of our time must be a vital function of our bodies”, says Nissen. “Otherwise evolution would have made a big mistake.”

There are two hypotheses: One is that sleep is important for the so-called neuronal plasticity, in other words the ability of synapses, nerve cells and whole areas of the brain to adapt and change. This is the basis for all learning. Every day lots of nerve cells make new connections and the brain needs to declutter in order to create more capacity. This means relevant synapses are preserved and strengthened and important things are deeply rooted in the memory and trivial stuff is forgotten. This decluttering tends to happen during periods of deep sleep. 

The second hypothesis is that harmful metabolic products that accumulate in the brain during the day are removed. This cleaning happens predominantly during sleep. If it is disturbed, essential processes in the brain are hampered. 

It is interesting to note that this process is slightly different for people suffering from depression. “A healthy person feels shattered after a poor night’s sleep. Someone suffering from depression will experience the exact opposite: A sleepless night can have a powerful effect on the following day and help alleviate the symptoms”, says the chief consultant. The problem with prescribing sleep deprivation as a form of therapy is that patients often fall back into depressive moods once they have caught up on their sleep. Sleep practically makes them ill again. “Highly interesting from a scientific standpoint is that it is possible to dramatically improve the state of depression within hours. The ability of nerve cells to connect together appears to be diminished in someone suffering from depression and presumably momentarily normalised through sleep deprivation.” 

Fact 3: all sleep is not good sleep

Some say you can sleep when you’re dead, and others would love nothing more than to spend the whole of Sunday in bed. So just how much sleep do we need? And Is it possible to sleep too much? “Sleep differs from person to person”, says Nissen. “and sleep requirements are very much individual”. The sacred eight hours that you tend to read everywhere is complete nonsense. A healthy person may need anything between five and ten hours of sleep. “Someone who only needs five hours of sleep probably lies awake in bed for three hours fretting that they haven’t had eight hours sleep and probably developing a sleep disorder because of it.” And those who toss and turn in bed, doze or whose sleep is often disturbed, do not build up enough sleep pressure for the night.

Which is why some people monitor their sleep with smart watches in order to build a clearer picture of how they sleep. Can this be useful? “It is relatively easy to monitor the activity rhythm between movement and rest. Although it doesn’t really help if you still wake up feeling tired in the morning. These watches do not give you the full picture.” The devices may indicate periods of sleep but not if certain areas in the brain are overactive. “We have recently discovered that individual areas of the brain remain active even if you are in a deep sleep. Your own impression of how you slept doesn’t necessarily need to correspond with what your watch indicates.” Imaging techniques in sleep research offer a clearer picture. 

Sleep hygiene: tips for healthy sleep

So-called sleep hygiene can help you improve your own sleep. But Nissen emphasises that it is vital that this term is not misunderstood. “It is not deemed unhygienic to drink a coffee in the evening or do sport late at night.” Rather it is a case of tips about how to sleep better that may help. Sleep hygiene can be particularly beneficial for older people as they often spend time alone, resting and indoors. 

1. Shorten your time in bed and set aside a time at night to sleep
How can I fall asleep quickly, even if I’m not tired? If your sleep is often disturbed the best thing you can do is shorten the amount of time you actually sleep. If you are spending too long in bed, you will end up dozing and not building up enough sleep pressure for actual deep sleep. It is also important to work out how much sleep you actually need. “It is not possible to make a precise measurement of your individual sleep duration”, says the doctor. “But you can make general observations and note your experience. How long do you tend to sleep for when you have fewer social and professional obligations, for example, when you are on holiday?” A sleep diary may offer insight. Long naps after lunch on the sofa are also detrimental and reduce sleep pressure which builds up during the day. 

2. Adapt your sleep window and go to sleep at regular times.
The second most important tip for healthy sleep: Adjust your rest time according to your own so-called chronotype. This means you should find out when you are most inclined to sleep. “Early birds and night owls really do exist. If possible, you should adjust your sleep window according to your particular type.” So maybe you sleep best between 10 pm and 4 am or 1 am to 7 am. Nissen likes to talk about a “wave”, or sleep pressure that is required in order to surf or indeed sleep. If you don’t catch the wave, then you won’t be able to sleep properly. 

3. Avoid taking medication if possible
“A big problem: Even today far too many traditional soporifics are still being prescribed that result in addiction and withdrawal problems”, says the chief consultant. And these sleeping pills cause poor sleep. Nissen’s team in Bern is currently developing the programme ‘Become your own sleep expert’. Even patients with severe psychiatric disorders should be able to improve their sleep with this programme. The optimum sleep windows/times are determined in groups and recorded in an App or diary with the help of the clinical team. The aim is to make this programme an over-the-counter medicine that can be prescribed by clinics and doctors in the same way that you can buy a change of dressing or medication.

4. Treat mental illnesses
Anyone who thinks they may be suffering from depression or another psychiatric illness should seek medical advice from their doctor. Poor sleep can be a symptom that may disappear again once the actual disease has been treated.

5. The supporting factors of sleep hygiene
It is important to lead an active life if you wish to make yourself really tired. Sport, exercise and positive social contacts can also help against stress. Plenty of daylight gives your body the right signals, and we feel tired when it gets dark at night. Your bedroom should be comfortable and not too warm: The ideal temperature is between 16 and 18 degrees. We also suggest having a ritual to wave goodbye to your working day. Avoid taking your laptop to bed in order to keep stress at bay. And other electronic devices such as the television should ideally stay in the living room. A glass of red wine is not necessarily a recommended nightcap. It may help you fall asleep faster, but your sleep will be restless. Nicotine also affects the quality of your sleep. And although we encourage social contact, you would do better to avoid a heavy meal in the evening and the subsequent coffee.