Meet 'Sleep', the guardian of your wellbeing galaxy | UniSC | University of the Sunshine Coast, Queensland, Australia

The brain is a very busy organ, using up lots of energy and performing complex tasks repeatedly. And because it’s highly active, metabolic waste builds up quickly, which means the brain needs to cleanse itself on a regular basis – just like the rest of our body (though, unlike the rest of our body, the brain doesn’t have lymphatic vessels to do the job).

So how then, does the brain remove its metabolic waste products? Amazingly, it’s only been in the last ten to 12 years that researchers have discovered how. The answer is, the glymphatic system, and this system kicks into gear while we sleep.

Dr Christina Driver, Lecturer in Mental Health and Neuroscience at UniSC's Thompson Institute, said sleep plays an extremely important role for brain health.

“While it is often thought that the brain is also resting when we sleep, research now suggests that the restorative role of sleep, may actually be due to the brain shifting into a functional state, whereby the glymphatic system works to clear neural waste products that build up when we're awake,” Dr Driver said.

"For example, metabolic by products such as beta-amyloid, the protein associated with Alzheimer's disease, can accumulate between our brain cells. If these protein aggregates are not flushed away by the glymphatic system, this can affect numerous brain functions, leading to short and long-term harm."

According to the 24-Hour Movement Guidelines (Department of Health 2017, 2019a), children and young people need eight to 17 hours of sleep a day, depending on their age.

Research has also shown that for adolescents, who commonly experience delayed sleep-wake patterns, poor quality and a lack of sleep is associated with higher scores on suicidal ideation scales.

"Unfortunately for a lot of young people, the interplay between early school start times and this circadian rhythm phase delay has been shown to result in severe sleep deprivation during the week and then trying to catch-up sleep on the weekends," Dr Driver said.

Humans spend roughly one-third of their lives sleeping. For most Australian adults, getting seven to nine hours of uninterrupted sleep is recommended, according to the Australian Institute of Health and Welfare.

"While most Australians are meeting national recommendations for how much sleep is required each night, many still experience some form of sleep problem,” Dr Driver said.

“In 2016, it was estimated that nearly half (48%) of all Australian adults had at least two sleep-related problems.”

Although there are guidelines for the amount of sleep we should be having at different stages of life, Dr Driver says the quality is just as important as the quantity.

“When we get enough good quality sleep, this can enhance many different aspects of cognition. Sleep can help improve memory, attention, concentration, problem solving, emotional processing, and judgment, and can even boost creativity."

She shared some well-researched methods to help improve your sleep quantity and quality, and said even “making one or two small changes can help.”

Methods to improve your sleep quantity and quality:

• Reduce light exposure in the evenings – use low/minimal lights before bedtime

Excess light can throw off your sleep and circadian rhythm. Avoiding bright light can help you transition to bedtime and contribute to your body’s production of melatonin. In the same way, viewing sunlight in the morning can help normalise your circadian rhythm.

• Minimise blue light exposure in the evening – no doom scrolling in bed!

The lights on our screens may trick our brains into thinking it is daytime, therefore potentially affecting melatonin release. Ideally, stop looking at a screen one to two hours before bed.

• Exercise every day but not too close to bedtime (due to increases in hormones like adrenaline and noradrenaline)

The changes exercise initiates in energy use and body temperature, can promote solid sleep.

• Limit caffeine later in the day and be mindful of alcohol consumption too close to bedtime

Alcohol can induce drowsiness, so it may seem like it is helping you sleep, but unfortunately, alcohol affects the brain in ways that can lower sleep quality.

• Try not to eat too close to bedtime

Large meals especially can affect hormones and sleep quality. Similarly, reduce fluid intake in the late evening and try to use the bathroom right before bed.

• Try to keep regular sleep and wake times

Your body’s circadian rhythm functions on a set loop, aligning itself with sunrise and sunset. So, being consistent with sleep and wake times can improve sleep quality in the long term.

• Optimise your bedroom environment

For example, minimise external noise, light, and artificial lights from devices, and create a bedroom that you find relaxing, with a comfortable bed.

• Have a calming pre-sleep routine

Strategies include listening to relaxing music, reading a book, taking a hot bath or shower, meditating, deep breathing etc.

• If you're struggling to fall asleep after 20 minutes, get out of bed

This reduces the chances of you building a connection between your bed and getting frustrated with not being able to sleep. Do something relaxing in low light like reading, but avoid checking the time or using electronics and go back to bed when you feel tired again.

• If sleeplessness is chronic, get help

If you are still struggling, make sure you chat to a medical professional to rule out a sleep disorder such as sleep apnoea, sleep movement disorders, and circadian rhythm sleep/wake disorders.