Why getting enough sleep is important for mental health, as study shows link between sleep and depression

A man wearing a grey hoodie lays on his bed with an arm over his face
Consistently not getting enough sleep has been linked to an onset of depressive symptoms. (Getty Images)

A bad night’s sleep can ruin the next day, but consistently not getting enough sleep can be damaging to your mental and physical health.

A new study has suggested that consistently sleeping fewer than five hours a night can increase the risk of depression. The results were similar between those who were genetically inclined towards sleeping for shorter periods and those who were not.

Researchers from University College London (UCL) analysed genetic and health data from 7,146 people recruited by the English Longitudinal Study of Ageing (ELSA) and found that short sleep was associated with the onset of depressive symptoms.

Professor Andrew Steptoe, head of Behavioural Science and Health, UCL Institute of Epidemiology and Health Care, said: “Suboptimal sleep and depression increase with age, and with the worldwide phenomenon of population ageing there is a growing need to better understand the mechanism connecting depression and a lack of sleep.

“This study lays important groundwork for future investigations on the intersection of genetics, sleep, and depressive symptoms.”

A woman sits in the dark with her hand on her head
Being unable to fall asleep can have a big impact on our mental health. (Getty Images)

Why is sleep so important for mental health?

Sleep is crucial for our bodies and brains to recuperate and rejuvenate after each day, and helps with overall functioning. When we consistently have poor sleep, it can profoundly impact how we function and feel, Lisa Gunn, mental health prevention lead at Nuffield Health, tells Yahoo UK.

Lack of sleep can lead to:

  • Poor emotional regulation

  • Stifled creativity and problem-solving

  • Reduced efficiency and productivity

  • Poor memory recall

  • Tiredness

  • Lack of motivation and concentration

Sleep and mood are also closely connected, Gunn says, adding: “It’s been found that poor or inadequate sleep can cause irritability and stress… Prolonged sleep deprivation has also been associated with depression, anxiety, and in extreme cases, thoughts of suicide or self-harm.”

How much sleep should we be getting?

According to the NHS, the average healthy adult usually needs around seven to nine hours of sleep. However, some people are genetically predisposed to sleep either less or more, and the amount of sleep you get can be affected by age, health and personal circumstances.

However, you may be suffering from sleep problems, such as insomnia, if you aren’t able to get an adequate amount of sleep often. Symptoms of a sleep problem include:

  • Finding it difficult to fall asleep

  • Lying awake for long periods at night

  • Waking up several times during the night

  • Waking up early and being unable to get back to sleep

  • Feeling down and having lower moods

  • Having difficulty concentrating

  • Being more irritable than usual

How do you treat sleep problems?

Luke Cousins, regional physiology lead at Nuffield Health, says that some sleep issues can be prevented by improving sleep hygiene. This refers to your sleep environment and behaviour before bed that can impact how much and how well you sleep.

He recommends:

Setting a routine

Stick to the same bedtime and activity times every day and try to avoid the temptation to nap. Aim to wind down at least an hour before bed.


A woman sits on her bed with a notebook on her lap and she is looking down and writing in it
Writing down what is bothering you before going to sleep can help you relax and put worries aside. (Getty Images)

To prevent worries from interrupting your sleep, take some time to write them down before you go to bed. Create a to-do list and postpone thinking about bothersome issues.

Making your bedroom a place to relax

Make sure the bedroom is dark, comfy and quiet. Good air quality and room temperatures are also important - the ideal room temperature for sleeping is between 16C to 19C.

Prioritising diet and exercise

Eat a balanced diet throughout the day and aim to avoid eating large meals for at least two hours before bed. Try to get at least an hour of exercise a day, but don’t exercise in the two hours before bed.

Turning off all electronic devices

A woman looks at her bright phone screen in the dark while she is in bed
The bright light emitted by your phone can disrupt natural sleep hormones, making it harder to sleep. (Getty Images)

Social media is addictive, but phones and laptops emit a blue light that can keep us awake and prevent the release of melatonin. Avoid looking at screens entirely for two to three hours before bed.

However, if you need help getting to sleep due to insomnia or other health issues, discuss treatment options with your GP. These might involve sleeping tablets which can only be taken for a short period of time, or cognitive behavioural therapy that can help you identify what is affecting your sleep and introduce new techniques to get to sleep.

More information about mental health: