This article covers ⬇️
- Why we sleep
- The optimal amount of sleep
- What is sleep hygiene?
Why do we need sleep?
There is a close relationship between sleep and health. Humans spend roughly 1/3 of their life asleep, yet understanding the depth of sleep physiology is something that still has many scientist scratching their heads.
What we do know, is that insufficient sleep is linked to 7 out of 15 leading causes of death, including cardiovascular disease, some cancers, diabetes and high blood pressure. Sleep additionally benefits cognitive performance and productivity, and reduces your risk of accidents at home, work and on the road . Sleep is vital for immunity. It ensures our immune system maintains its immunological memory and is able to fight illness and disease .
There is particular emphasis on the long term, and possibly irreversible, effects of sleep deprivation on young people. It can contribute to:
- Reduced academic performance and cognitive ability .
- The onset of mood disorders such as depression, especially if other risk factors such as family history and stressful life events are also present .
what’s the Optimal amount?
We all appreciate a good night’s sleep, not to mention being able to make it through the afternoon without the burning desire for a post-lunch snooze. Insufficient sleep is an increasingly relevant problem globally, but especially in industrialised countries such as the United Kingdom. The need for us to keep up with a restless modern society that functions 24/7 prevents an alarmingly large number of us from sleeping enough each night, and this is associated with numerous mental and physical health issues .
What then is the optimal amount of sleep?
This varies throughout your lifespan and steadily decreases from birth; the National Sleep Foundation recommends that young adults and adults sleep for 7 to 9 hours, while 7 to 8 hours is appropriate for older adults .
What is Sleep hygiene?
You may have heard this term thrown around, and no it does not refer to the quality of your hand washing and tooth cleaning pre-bed! Your sleep hygiene is the combination of good and bad habits you practise that affect the quality of your sleep and therefore how well you function during the day.
Sleep hygiene tips
What constitutes ‘good sleep hygiene’?
Most importantly, we should sleep for an optimal duration of time for our age group; too much or too little could both adversely affect our daytime alertness.
Other good sleep hygiene habits include:
- Limiting time spent napping during the day. While a power nap can be a quick fix to lift your mood and improve your productivity, it cannot compensate for poor nighttime sleep. Limit naps to 30 minutes if possible!
- Staying away from the caffeine and alcohol around evening time. While a glass of red is renowned for provoking that urge to snooze, both of these have stimulant properties and are disruptive to sleep.
- Daytime exercising. This can be as little as 10 minutes of walking or cycling! Daily exercise can significantly improve sleep quality.
- Avoiding foods that cause indigestion and heartburn close to bedtime. This includes rich, fatty, spicy or fried food, in addition to citrus fruits and carbonated drinks. In other words, give yourself some time to digest that hot curry before attempting sleep.
- Adopting a relaxing bedtime routine that signals to your body it is time to sleep. This could include reading or showering. Avoid strenuous activities and emotionally upsetting conversations pre-bed if possible.
- Creating a good sleep environment. This includes optimising bed comfort, a room temperature between ~16-19°C, dim lighting, and blackout curtains, eye shades and ear plugs if necessary. Avoiding bright phone and laptop screen lights and using machines that create white noise, such as fans, can aid relaxation. 
- Avoiding brightly lit environments just before bed. Melatonin is a hormone that plays a role in your natural sleep-wake cycle. Levels should rise at night to promote entry into sleep, and this is encouraged by reduced light levels. After-dark light prevents the natural rise in melatonin, essentially tricking your brain into thinking it is not yet time to sleep. 
- Maintaining a healthy sleep-wake cycle by ensuring you are exposed to enough natural light throughout the day – this keeps melatonin levels low until nighttime . If you are working from home, a well lit working space could make that crucial difference to your sleep quality .
Signs of poor sleep hygiene:
- Night time sleep disturbances
- Sleepiness during the daytime
- Taking too long to fall asleep. 
If any of the above apply to you, consider making changes to your pre-bedtime routine.
What is insomnia?
Insomnias = disorders causing difficulty falling or staying asleep.
A common condition in the UK, studies suggest as much as 37% of the population experience symptoms. These include:
- Difficulty falling asleep
- Difficulty remaining asleep
- Waking too early. 
Insomnia is mostly chronic (occurring over months to years). It can be linked to psychiatric disorders such as anxiety, depression and eating disorders. However, acute insomnia can result from stressful life events such as job loss and bereavement .
As insufficient sleep can affect all aspects of a person’s life, insomnia can be highly detrimental to our mental and physical health. Insomnia treatments can involve both targeting behaviour and sleep hygiene habits to eliminate contributing factors, and pharmacological therapies such as hypnotics if necessary.
Written by Jessica Atkinson BSc (Hons)
Edited by Rebekah Jade BSc (Hons)
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