Sleep. We all need it. How much, where, when – all depends on our circumstance, preference, and lifestyle. But it’s vitally important for our mental and physical health, whether we’re growing up or growing old. Sleep ‘hygiene’ is becoming a buzz-word, one perhaps that we might associate with reading those mattress adverts on the tube. Why should we be ‘hygienic’ about our sleep, and why might our parents just possibly have been right to insist on those oh-so-sensible bed times once when we were too little to decide for ourselves?

The architecture of sleep, as it’s referred to, has three distinct states. Wakefulness, NREM (non-rapid -) and REM (rapid-eye-movement) all represent different phases of neuro/physiological regulation with associated consciousness changes which can be mapped using an EEG to observe levels of brain activity. Broadly, as body activity reduces, and humans fall asleep, brain waves get slower and bigger, allowing 90-minute cycles of REM and NREM sleep to occur. During the deepest phase of sleep (‘slow wave’ sleep), growth hormone bursts occur, and the brain can restore its supply of ATP, the body’s best immediate energy source. While no-one really seems to be sure WHY we sleep, a huge variety of reasons have been proposed over the years, including regulatory metabolic and immune functions, as well as memory consolidation and waste clearance.

Whilst the jury is out on finding the definitive answer as to the reason that we all spend on an average of 25 years of our life asleep , the impacts of trying to fit in just one more episode of your favourite TV-drama at a time where you should be ‘away with the fairies’ (couldn’t find any evidence for this folks), are both well-documented and profoundly common at a time where we are constantly demanding more from our walking hours. Disruption to our circadian rhythm most commonly leads to fatigue with an increased probability of accidents, poorer concentration and impaired cognitive function. Hormones such as cortisol and TSH (thyroid-stimulating hormone) rise during sleep deprivation, contributing independently to the perhaps chronic stress state in which many of us find ourselves (and may consequently be found reaching independently for that 3pm chocolate biscuit). Worse than this, studies are demonstrating links between sleep debt and obesity, with an increased risk of developing type 2 diabetes resulting from as little as 30 minutes of sleep deprivation each day . Incredibly, in 2009, the Danish government paid compensation to a cohort of women who developed breast cancer after a long period of working at night ; although the link to malignancy has yet in no way been substantiated, the case was tribute to the fact that we still don’t fully understand the severity of consequences of this seemingly most basic of functions.

Sleep hygiene is a huge topic and refers to a variety of different practices and habits that are important to pay attention for good quality sleep and full daytime alertness. Common advice includes going to bed and getting up at the same time each day, with regular (preferably morning) exercise. Keeping the sleeping area dark and free from distractions – especially when it comes to setting the apple-iPhone alarm for that 6am wakeup –is key, as is preparing yourself physically and mentally for sleep by unwinding at the end of the evening with a non-caffeinated drink or a warm bath. The most common cause of insomnia is a change in daily routine, such as travelling or work stress, so looking at other ways to relax, such as mindfulness will also help. Evidence is still outstanding for other wives-tales such as Lavender (one RCT tested inhaled lavender in combination with sleep hygiene techniques and found improved sleep quality in the intervention group, although further follow-up was recommended to demonstrate ‘sustained’ effects).

In conclusion, similar profiles of sleep deprivation may be linked to other common-place nasties like stress, poor routine, lack of exercise and time outside, and poor diet. Addressing these before our head hits the pillow will certainly help us drop off, and live well, too. What’s stopping you from sleeping? Is there anything about your routine that you can ‘clean up’? It might be more important than you realise.


[1] Neurophysiology of sleep and wakefulness. Literature Review in Respiratory Care Clinics 11(4):567-86 · January 2006
[2] Based on an average life expectancy of 75 years, at 8 hours of sleep/night.

[3] The Impact of Sleep Debt on Adiposity and Insulin Sensitivity in Patients with Early Diabetes: LBT 097-116-Late-breaking Diabetes & Glucose Metabolism. Hall D-F. Thursday, March 5, 2015: 1:00 PM-3:00 PM, Diabetes (San Diego Convention Center).

[4] Article, Nigel Morris – August 2015, The Independent Online.

[5] Article, The Sleep Foundation.

[6] Effect of Inhaled Lavender and Sleep Hygiene on Self-Reported Sleep Issues: a Randomized Controlled Trial. Lillehei AS, Halcón LL, Savik K, Reis R. Journal of alternative and complementary medicine, NY 2015.