Why a good night's sleep is crucial for mental health


Despite the fact that we all do it, sleeping remains one of the most prevalent mysteries of science. While there are many theories as to why humans need to sleep when many other animals do not, the truth is we don’t actually know. What we do know is that sleeping is intrinsically linked to our mental health. Below we look at some of the research behind the link between mental health and a good night’s sleep.

Different Types Of Sleep

You may not realise it, but when you go to sleep, you are not simply going to sleep. Between the times your head hits the pillow and you get up in the morning, you actually alternate between two very different kinds of sleep. The first is deep sleep, during which our bodies essentially minimise the level of work they do. Our breathing and heart rates slow down, our core body temperature drops, and our muscles relax. This cycle gives our body a break and helps us stay physically healthy. If you think of your body as a factory, this is when all the workers go home and the machinery is given a chance to cool down.

The other category of sleep is known as REM sleep, which stands for Rapid Eye Movement. This is when we are dreaming, and is so called because our eyes can often be seen moving under their lids as we dream. During REM sleep, our bodies operate at more or less the same levels as when we are awake. We think that this allows our minds to process the information we absorbed during the day, which helps our memory, learning ability, and cognitive abilities. In the factory analogy, this is when the employees are working behind the scenes to get the affairs in order.

Generally speaking, we switch between the two types of sleep every hour and a half. Sleep disorders or disturbances can disrupt this cycle, which will reduce the quality of the sleep and have knock-on effects for our health.

Effects On Mental Health

Failure to get a good night’s sleep can affect our mental health in both direct and indirect ways. Perhaps the most obvious way in which our mental health is affected is through grogginess, or the inability to process information that would ordinarily be easy for us. When our minds have not rested sufficiently, they will attempt to use as little energy as possible. This means that our brains are ‘shutting down’ more often, and not operating at full capacity even when we are thinking. This affects our minds both directly and indirectly, as we become cranky and frustrated at our inability to do things we know we can.

A lack of sleep does not only impact our mental health from a physiological standpoint, but also from a social one. People who have trouble sleeping will have less energy to go out, meet friends, work, carry out tasks successfully, and so on. When all of these factors combine, they can affect us in a variety of ways. We become more isolated, as we don’t want to go out, but are also not in the mood to socialise. This alone lowers our self-esteem, which is also lowered by our inability to learn or comprehend new information, and fewer tangible successes in life. Our grades drop, we perform worse in work, we even have less energy and drive to invest ourselves in the things we enjoy, all of which impacts our immediate mood, and ultimately, our overall mental health.

With over 70 identified sleep disorders, as well as factors such as diet and exercise, it can be difficult for us to identify exactly why we are having trouble sleeping. While it is normal to have the occasional bad night, or even a period of sleepless nights (because of exams, grief, etc), you should not be experiencing trouble sleeping consistently for extended periods of time. If you are, visiting a specialist is by far the most effective way of identifying the root cause of your troubles and overcoming them. One of the most amazing things about sleep is that the effects of high-quality sleep are near-instantaneous, so if you are having trouble getting to sleep at night, don’t wait any longer to address it. 

David Clarke