Insufficient sleep is bad for your mental health

Insufficient sleep is bad for your mental health

Insufficient sleep isn't just a consequence of mental health difficulties; it can lead to depression, anxiety, stress, anger, and other problems too. This article outlines some of the negative effects of poor sleep on our mental health.

It’s widely known than mental health difficulties such as depression, anxiety, and being stressed can disrupt sleep. At Lemons to Lemonade we often hear therapy clients telling us they can’t get off to sleep, or can’t get back to sleep if they wake during the night, because difficult thoughts keep them awake. It’s less well known that having insufficient sleep can itself be harmful to our mental health. Most of us need somewhere between seven and nine hours of sleep every night. In modern societies, it’s quite common to have less than this. There are twin pressures on our time: fitting in all the demands of home life and social life in the evenings, and the need to be up in the mornings to meet the demands getting to work and/or getting children to school. These can lead us to averaging only six to seven hours’ sleep, or even less: we may not realise it, but we’re chronically sleep-deprived. Sleep deprivation can be even worse for those of us who have to work varying shift patterns.

Sleep deprivation has a host of detrimental effects on our mental life. Let’s look at some of them.

First, let’s consider the relationship between poor sleep and common mental health difficulties. Scientific studies have shown that if we’re deprived of enough sleep, the connections in the brain between the amygdala, where negative emotions such as fear, anxiety, and anger arise, and the cortex, that’s responsible for rational thought and which acts to regulate those negative emotions, are weakened. This release of inhibition from the cortex means that we feel negative emotions more strongly when we’re sleep-deprived. This makes us more vulnerable to depression, anxiety, and anger. The connections between the cortex and the striatum, where positive emotions are generated, are also weakened, so we can also feel positive emotions more strongly. This can lead to behaviours like excessive sensation-seeking, pleasure-seeking, which can lead us into difficulties in our social relations, and addiction.

This means that not only do mental health difficulties cause us to sleep badly, but also poor sleep itself leads to mental health difficulties. It’s what psychologists call a “maintenance loop”: poor sleep reinforces mental health difficulties, which in turn reinforce poor sleep, and so on.

Second, poor sleep impairs our ability to form new memories. Every night, memories from the day are transferred from short-term to long-term memory while we sleep; if we don’t get enough sleep, some of these memories never make it into long-term storage and are lost. Poor sleep has various other bad effects on memory that we don’t have space to discuss here.

Third, poor sleep leads to us having “microsleeps” during the following day – moments, a few seconds long, where we lose conscious awareness. In concentration tests, being awake for 19 hours continuously has been found to be as harmful to our ability to concentrate as being over the legal alcohol limit for driving. This can have devastating effects. Figures from the AAA Foundation for traffic safety, an Amercian charity, show that having only 5-6 hours’ sleep increases your risk of crashing your car by nearly twice, and having less than four hours’ sleep makes you over eleven times more likely to crash.

Luckily there’s a proven answer to sleep difficulties; and no, it’s not sleep medication, which is only a short-term fix. The top recommendation of the National Institute for Health and Care Excellence (NICE) is a psychological therapy, Cognitive Behaviour Therapy for Insomnia (CBT-I), which we offer at Lemons to Lemonade. If you recognise you’re sleep-deprived and want help, you can contact us by email at or by phone on 07376 010506.

This is the first in a series of three blogs about sleep. You can read about what happens when you sleep normally in the second blog, here: