The Importance of Sleep For Health
It seems we are suffering from a sleep deprivation epidemic – enough to cause the federal government to call for a parliamentary inquiry into sleep health awareness in late 2018. In 2017 the National Sleep Foundation commissioned a review on sleep health. The review found that almost 40% of Australians report getting inadequate sleep. The review went on to describe the impact on a range of factors to do with health, wellbeing and productivity. It estimated the cost to individuals, workplaces and the health system of around $40 billion.
Sleep is fundamental to health. Disordered sleep is common to many mental illnesses, including depression, post-traumatic stress disorder and dementia. In addition, there are lifestyle factors that impact sleep quality, including shift work, being overweight, alcohol use and computer screen usage after dark. Feeling drowsy before midday is a sign that you are not getting enough sleep. Other signs include “foggy brain” and problems with memory recall.
We need sleep to learn. Sleep allows the brain to undertake a range of functions necessary for good brain health - including washing the brain, remodelling neural circuits, organising storage space for new information and transferring short-term memory into long-term memory. Our memory is a massive storage system that contains all the information that we need to make our way in the world. If we can’t remember, we don’t learn, and we will find that managing life is more difficult. Inadequate sleep ages the brain.
Sleep helps creativity. During REM (rapid eye movement) sleep, many of the emotional regions of the brain become active, with associations (i.e. dreams) being made between new information and information in long-term memory storage. “Sleeping on a problem” makes sense and often we awake with a solution or insight that seemed previously elusive. During sleep, our brain has “joined the dots”. In healthy people, sleep is inevitable and is regulated by two hormones – melatonin and adenosine. Melatonin acts as a signal generator, sending a message to the brain that it is time to sleep. But melatonin doesn’t make us sleep. This is the job of adenosine, which acts like a chemical pump that builds up pressure during waking hours, creating a desire to sleep. It acts like a bank – when the mortgage is due, we must make payment or face the consequences.
Create a healthy sleep routine. Try to regulate sleep according to your body’s natural clock. Going to sleep and waking up at the same time creates a good “sleep habit”.
Prefer books to screens before bed. LED-powered devices (e.g. tablets) suppress melatonin release and disrupt REM sleep. Late-night catching up on work emails might make it harder for you to recall information the next day.
Avoid over-heating. A cooler room temperature is better for sleep.
Moderate caffeine and avoid alcohol before bed. Although alcohol is a sedative, it disrupts the brain functions that regulate sleep. Alcohol suppresses REM sleep, which can have serious consequences for brain health over time.
Retrain your brain. Cognitive Behavioural Therapy is recommended as a first-line treatment for insomnia. It targets the mental (or cognitive) factors such as the racing thoughts and worry that are part of sleep difficulties and the behavioural factors that help create the right environment for sleep, helping the mind re-establish a positive anticipation about sleep.
There is much more to sleep than we might imagine. If you are having difficulties with sleep, think about improving your sleep habits. If problems persist, have a chat with your GP.
Anne Ward is principal psychologist of Mindinsight, providing evidence-based psychology services to adults, children and adolescents. Mindinsight is located in the T&G Building at 45 Hunter Street Newcastle. Visit www.mindinsight.com.au or phone 4942 7660.