The Importance of Sleep to our Mental Health

By Jolene and Krisha

Vetted by Dr. Reena

According to Suni and Dimitriu (2023), sleep is closely connected to mental and emotional health, with demonstrated links to depression, anxiety, bipolar disorder, and other conditions. While research is ongoing to better understand the connections between mental health and sleep, the evidence to date points to a bidirectional relationship. Mental health disorders tend to make it harder to sleep well. At the same time, poor sleep, including insomnia, can be a contributing factor to the initiation and worsening of mental health problems (Suni & Dimitriu, 2023).

Our natural sleeping and waking hours are determined by our circadian rhythm, which lasts about 24 hours and is influenced by the sun and the amount of light in our environment. People vary in circadian rhythm, with some being more active in the morning and some more active at night. To signal your body’s circadian rhythm to sleep at your desired time at night, it may be helpful to get proper light exposure in the day and turn down the lights at night.

When we sleep, we go through several rounds of the sleep cycle. Our sleep cycle has the following stages: 2 stages of light sleep, 1 stage of deep sleep and then REM sleep. Deep sleep is important for ‘repairing’ our body after a day’s work. REM sleep occurs after about 90 minutes of falling asleep. Vivid dreams often occur in this stage such as nightmares or eventful dreams. REM sleep is thought to help in consolidating memories formed recently, especially that of emotional events (Summer, 2023; Suni & Vyas, 2023).

Obstructive sleep apnea (OSA) is a common sleep related breathing disorder (Povitz et al., 2014). There is more to OSA than just snoring: it involves pauses in breathing during sleep and a reduction in the body’s oxygen levels due to obstructed airways, creating fragmented and disturbed sleep. OSA has significant adverse effects on a person’s overall well-being. OSA is associated with higher rates of Major Depressive Disorder (Gupta & Simpson, 2015), increased daytime fatigue, heightened risks of cardiovascular problems (Johns Hopkins Medicine, 2022), and cognitive problems (Stranks & Crowe, 2016). Cognitive impairments include memory loss, lowered processing speed and difficulties with attention.

According to Spicuzza et al. (2022)’s research, the COVID-19 pandemic had a bigger impact on patients with severe OSA, as these patients’ perceived sleep quality and mental health deteriorated even further. Poor sleep quality leads to increased stress and susceptibility to depression, and these 3 factors form a vicious cycle, especially for patients with OSA.

However, OSA can be managed through treatments such as continuous positive airway pressure (CPAP), mandibular advancement devices (MADs), oral appliances and surgery. CPAP is a commonly used treatment for OSA as it is safe, non-invasive and highly effective. Every night, the patient wears a small mask that fits securely over the person’s nose and mouth, and the mask is connected to the CPAP machine which quietly and gently pumps in pressurised air to keep a person’s airways open throughout. Besides improvements in sleep quality, CPAP is also known to improve depressive symptoms (Povitz et al., 2014; SingHealth Duke-NUS Academic Medical Centre, n.d.; Spicuzza et al., 2022). Hence, if you find yourself excessively tired during the day and others have told you that you snore a lot in your sleep, we suggest you get yourself checked for sleep apnea and seek treatment as soon as possible.

Both sleep and mental health are complex issues affected by a multitude of factors, but given their close association, there is strong reason to believe that improving sleep can have a beneficial impact on mental health and can be a component of treating many psychiatric disorders.

Poorer sleep is associated with the following negative consequences:

1. Depression

2. Anxiety

3. Paranoia

4. Hallucinations (such as in bipolar disorder or schizophrenia)

5. Memory and cognition problems, along with drops in alertness

Freeman et al. (2017) found that after receiving treatment for insomnia via digital cognitive behavioural therapy (CBT) through the Sleepio treatment programme, university students had reduced paranoia (-58%) and hallucinations (-39%), along with lowered depression and anxiety.

This is further supported by Blackwelder et al. (2021)’s study for the Centers for Disease Control and Prevention (CDC), which found that U.S. adults who had insufficient sleep (less than 6 hours of sleep per night) were 2.5 times more likely to experience increased mental distress. Poorer quality sleep worsens depressive symptoms and increases the risk of developing depression (Chen et al., 2012; Chattu et al., 2018). Hence, there is a lot of research suggesting that improving your sleep quality can improve your mood and overall mental health.

Besides mental health problems such as depression or anxiety, poor sleep hygiene contributes to poorer sleep quality. Furthermore, the following factors were associated with poorer sleep quality:

1. Playing video games excessively, especially nearer to bedtime. The intensity of video game playing was a more important factor than the absolute amount of time spent on playing video games (Altinas et al., 2019).

2. Using electronic media, especially if done in bed or shortly before bedtime. Avoid surfing the internet or scrolling through social media before bedtime! (Lemola et al., 2015)

3. Caffeine intake is negatively associated with sleep quality (Wang & Biro, 2021). Avoid drinking too much coffee or tea, especially in the few hours before your intended bedtime.

4. Alcohol makes it more difficult to fall into deep sleep.

5. Irregular sleep schedule.

6. Heightened stress levels.

Practising mindfulness to relieve stress was found to significantly improve sleep quality, depression and anxiety (Chen et al., 2020). Regular exercise timed properly is also associated with better sleep quality (Wang & Biro, 2021).

Taking control of your daily sleep schedule is an essential step towards getting better sleep. To start building a healthier sleep schedule, you can try implementing these strategies into your daily routine:

1. Set a Fixed Wake-Up Time: It is close to impossible for your body to get accustomed to a healthy sleep routine if you are constantly waking up at different times. Pick a wake-up time and stick with it, even on weekends or other days when you would otherwise be tempted to sleep in.

2. Budget Time for Sleep: If you want to make sure that you are getting the recommended amount of sleep each night, then you need to build that time into your schedule. Considering your fixed wake-up time, work backwards and identify a target bedtime. Whenever possible, give yourself extra time before bed to get ready for sleep.

3. Be Careful With Naps: To sleep better at night, it is important to use caution with naps. If you nap for too long or too late in the day, it can throw off your sleep schedule and make it harder to get to sleep when you want to. The best time to nap is shortly after lunch in the early afternoon, and the best nap length is around 20 minutes.

4. Adjust Your Schedule Gradually: When you need to change your sleep schedule, it is best to make adjustments slowly and gradually, with a maximum difference of 1-2 hours per night. This allows your body to get used to the changes so that following your new schedule is more sustainable.

With better sleeping habits, it is likely that you will see more positive effects in other aspects of your life such as an improvement in mood and increased productivity.

References

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Blackwelder, A., Hoskins, M., & Huber, L. (2021). Effect of Inadequate Sleep on Frequent Mental Distress. Preventing Chronic Disease, 18, E61–E61. https://doi.org/10.5888/pcd18.200573

Chattu, V., Manzar, Md., Kumary, S., Burman, D., Spence, D., & Pandi-Perumal, S. (2018). The Global Problem of Insufficient Sleep and Its Serious Public Health Implications. Healthcare, 7(1), 1. https://doi.org/10.3390/healthcare7010001

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