The life saving benefits of good sleep

Sheena Fraser

As a GP and mum to three children I have had my fair share of sleep deprivation over the last 20 years.

In fact, at no stage during my junior doctor years of 32 hour shifts, or my breast feeding days of three-hourly feeds, did anyone explain to me that the lack of sleep would be harmful to me, not just at the time but later in life too.

It was much later after attending a lecture on sleep in my 40s that it suddenly dawned on me that I should have given this natural physiological process much more of my attention.

Living in a covid world is making us all look at our health and in particular what makes us vulnerable to the effects of Covid-19. Sleep may not be the first thing we think of in the fight against the virus but I’m going to share with you why I think it should be taken much more seriously.

Sleep isn’t just for restoring our energy levels and resting our tired muscles. Our bodies are hard at work while we slumber and some of these physiological processes are fundamental to our fight against covid.

Immune function

We rely on seven – nine hours sleep as an adult to develop long-term immunity to disease and to maintain healthy immune cells to fight infections and cancer cells. Our microbiome (the trillions of microorganisms which share our bodies and perform many important tasks for us) thrive on seven – nine hours sleep but sadly the variety of helpful organisms diminishes with less than five hours sleep.

In an experiment in California participants given a dose of the common cold virus up their noses had a 50% chance of developing cold symptoms if they slept five hours or less. However, they had only an 18% chance of developing symptoms if they slept for seven to nine hours. Our response to vaccines are also enhanced by seven – nine hours sleep, with sleep deprived individuals only developing 50% of the immune response compared to those who had slept seven – nine hours.

If we are sleep deprived (less than five hours sleep) then our immune function is impaired and this can lead to more serious or prolonged infections and an increased likelihood of cancer.

Sleep and metabolism

Sleep aids our metabolism which helps us to balance insulin and glucose and regulate our weight. A lack of sleep increases our appetite and leads to our calorie intake hiking up by 370 calories per day which can result in weight gain and diabetes. We are all now aware of the additional risk that obesity and diabetes pose to us with covid.

Sleep and learning

At a time when the schools, colleges and universities are closed and we are having to do more home learning, sleep can cement new learning and aid the processing of new information. Sleep deprivation on the other hand will reduce our concentration and impair our memory making studying much harder.

Sleep and stress

Living in a covid world is stressful. We face health anxiety, bereavement and social isolation. We are confined to our houses during lockdown, and spend much more time with our immediate family. For some, this is a really positive experience getting to spend more time with the ones we love the most, but for others it can lead to stress, disharmony, arguments and fights. In the worst cases this has led to psychological and physical abuse within families.

Getting seven – nine hours of good quality sleep can help reduce our cortisol levels lowering our anxiety which helps us to stay calm and manage stress better. REM sleep can help us to process difficult emotions and experiences reducing our likelihood of anxiety, depression, PTSD and prolonged grief reactions and help us remain positive and stable with our mood. We all have a better chance of getting through lockdown unscathed if we prioritise our sleep.

Sleep and ageing

At a time when we are more socially isolated and lacking in stimulation through social interaction, activities and travel I have noticed that several more vulnerable older patients of mine have started to lose their memory and show signs of dementia. Whilst the cause of dementia is multi factorial there is a clear correlation between lack of sleep and cognitive decline.

The Glymphatic system is a system of lymphatic fluid (CSF) composed in glial cells, which pulses through our brains during deep non REM sleep. Its purpose is to remove the harmful metabolic contaminants produced by the hard working neurons in the brain. Think of it like a intensive wash for the brain every night. One of the most important by-products we remove is amyloid protein. Failure to remove this protein causes it to build up in the brain – and this has been detected in the brains of people with Alzheimer’s disease.

Sadly one of the first places amyloid is deposited is in the mid frontal lobe which is a key area for sleep initiation. This can worsen our sleep and lead to an acceleration of amyloid deposits and advances the disease process. Sleep deprivation leads to high blood pressure and 200 times the risk of ischaemic heart disease through furring of our arteries. Maintaining good vascular circulation to the brain is essential in preventing vascular dementia and strokes. A good long sleep is therefore an essential means to help prevent dementia.

Sleep well

So, how do we achieve the perfect seven – nine hours of unbroken sleep per night? Our best chance is by following tried and tested sleep methods such as maintaining the same sleep and wake time each day, having a dark, cool and quiet room to sleep in, omitting bright or blue light 1-2 hours before bed, cutting caffeine after 2pm, and avoiding alcohol.

We reset our circadian rhythms with regular mealtimes, exercise and sunlight exposure. This list is not exhaustive and more information is available on If you are a shift worker you may need to work a little harder to maintain a healthy sleep work balance. There is additional information specifically for you on the Sleep Council’s website.

If you have suffered from insomnia it may seem like an impossible task to improve sleep. However, CBT and sleep restriction has an excellent success rate so is worth a try. Ask your doctor how to access this or there are many self help books to try. Head to to find out more.

Having optimised my own sleep hygiene and after working on getting my kids to have good sleep routines I am now sleeping 7.5-8hours a night, I have lots of energy during the day, I rarely catch infections, my mood remains positive and I can cope with the busy life I lead. It’s worth remembering that children need more sleep for their growth and development. My children are sleeping for 10 hours a night and are benefitting from a positive outlook, stable mood, bags of energy and excellent concentration and memory when it comes to school work.

I hope this inspires you to think about your sleep day to day, measure it, note down what works well for your sleep and what doesn’t, try to maintain healthy routines to aid your sleep and see how you feel when you reach those perfect seven – nine hours of uninterrupted sleep. It may even save your life!