When it comes to your health and wellbeing, there are four main pillars of health; regular exercise, good nutrition, dealing with stress and getting enough sleep.

But sleep is often a neglected element of our health. We don't tend to think too deeply about it. However, having a good night's sleep is vital for our health and wellbeing. After all, we are asleep for a third of our lives, so nature must have built in this vital habit for very good health reasons.

Some scientists have described sleep as nature’s own life support system. It’s ‘non-negotiable’ and we cannot survive without it. To put this in perspective, we can go without food for weeks, but the longest ever recorded ability to stay away is only eleven days, with most people unable to go without sleep for around three days.

But there are also significant health issues arising from sleep deprivation, especially if this is a regular or chronic occurrence.

A new piece of research from Nuffield's Healthier Nation Index (HNI) performed across the UK on over 8000 over 16s showed that 74% of adults reported a decline in sleep quality over the last 12 months. Furthermore, what was particularly worrying was that 1 in 10 adults reported that they were getting only between 2-4 hours of sleep per night! This amount of sleep deprivation is clearly injurious to our health in so many ways as has been shown in medical sleep research repetitively.

When we are awake, we tend to generate small amounts of a biochemical called ‘adenosine’ which builds up throughout the day. It is this adenosine which causes what the scientists call ‘sleep pressure’ to build up, with its end point and its objective of helping us to sleep and enter the various cycles of sleep , which are repeated throughout the night.

What are these Sleep Cycles Through the Night?

There are actually four different cycles that a healthy person will typically exhibit throughout the night.

In essence, these two main groups of sleep cycles are REM and non-REM sleep. REM simply means ‘rapid eye movement’, which describes how the eyes dart back and forth under the closed eyelids. This is also the part of sleep where we dream. The main cycles are as follows:

NREM 1(1-5 mins): When we start to fall asleep, we enter Non-REM Stage 1 (NREM 1). This is very light sleep in which we are starting to doze off, perhaps with some initial twitching. Heart rate slows as does breathing, muscles start to relax and we switch from mostly beta wave activity to alpha waves.

NREM 2 (10-60mins): This is deeper sleep and we spend around fifty percent of our sleep in this stage throughout the night. Brain waves slow down, but with occasional bursts of activity called ‘sleep spindles’

NREM 3-4 (20-40 mins): This is very deep sleep and is clearly the most restorative part of our sleep pattern. Sleep talking and even sleep walking will occur in this stage. In this stage the brain also undergoes a very important controlled ‘wash-through’ process, in which cerebro-spinal fluid gently removes various toxins such as amyloid beta proteins. Read below for more details.

REM Sleep (10-60 mins): This is the stage in which most powerful dreaming occurs, together with eye movements, whose reason is still unknown. Heart rate increases again together with respiration rate too. Arousal and awakenings can occur more easily during REM sleep.

These various cycles repeat every 90-120 minutes, resulting in around four or five such cycles every night.

How Much Sleep do we Really Need?

Whilst people may believe it is a myth, eight hours sleep is actually the recommended target duration according to sleep scientists. There are some people that seem to be able to function on less than this, however, this lack of sleep is likely to cause health issues later in life. The ‘I’ll sleep when I’m dead’ protagonists, fail to realise what long term damage they are doing to their health and certainly to their brain health.

In fact, we are now sleeping less now, than ever before! Data tells us that in the early 1940’s we slept on average 7.9 hours per night. Now we sleep for only 6.31 hours each night, which means that much of the population will be getting less than just six hours a night. This is a very unhealthy practice as we will discuss below.

Unfortunately, there is a growing number of people struggling with sleep loss. With impacts such as busy work schedules and an increase in stress levels, sleep often gets pushed to the bottom of priorities.

What are these Health Problems linked to Poor Sleep?

While poor sleep or lack of sleep will have a negative impact on our overall health across many areas, there is no doubting the benefits of good quality sleep and regular daily sleep patterns.

Your Weight

Perhaps one of the most underappreciated benefits of good sleep is controlling your weight. Scientific studies show that lack of sleep has been linked to higher body weight (BMI) and even obesity, which itself can lead to a list of other downstream diseases such as diabetes and cardiovascular diseases, including strokes. Other clinical studies showed a reduction in muscle mass too, which in itself is another unhealthy direction to head.

Sleep deprivation can also disrupt the so-called circadian rhythm (daily internal clock) and so in turn, can disrupt appetite hormones too, like ghrelin that stimulates appetite - increasing the desire to eat more.

Your immune system

A key aspect of health that benefits from getting enough sleep is the immune function. When our immunity falls, we are unable to fight viral or bacterial infections particularly well - leading to a greater risk of acquiring a variety of diseases.

One important facet of our immune system is the so-called “Killer Cells”, which behave as our ‘immune assassins’, protecting us against a large number of pathogens or disease-causing invaders.

Clinical studies show that even losing just four hours of sleep in one night, is enough to cause a 70% loss in immune function. Imagine the impact on our immune system if we continue to have poor sleep patterns for months or even years.

Your Cognitive Function and Overall Brain health

Enjoying a good night’s sleep supports various aspects of brain function, cognitive ability and memory too, all-important to retain as we age.

Sleep typically gets worse with age, as we tend to generate less sleep pressure than when we were younger. However, it also becomes more important too - it’s one of the best things to help with the overall aging process.

Dementia and Alzheimer’s Disease

More recently, sleep scientists have observed a strong link between lack of sleep and cognitive decline and even Alzheimer’s disease.

Neuro-imaging studies of the brain show that during deep sleep, the cerebrospinal fluid in the brain exhibits a kind of ‘washing’ through the brain, a natural way of removing problematic toxic protein bundles called ‘beta-amyloid plaques’. In essence, this is rather like the sewage system of the brain, cleansing the toxic proteinaceous debris that is not needed.

However, the presence of these protein plaques is well associated with Alzheimer’s disease, so deprivation of sleep is believed to be a cause of the memory debilitating disease later on in life. Many such experiments show that a lack of sleep can cause a rapid build-up of these plaques, even after just one night of poor sleep. Imagine this effect after a week or a month or even years of deprived sleep!

Once the plaques have been observed in the brain via imaging,  even the most modern medications are not particularly effective in removing these plaques or making a real difference to an Alzheimer’s patient.

Some scientists have even hypothesised that sleep disruption could even be a proxy biomarker for this disease, though this is not proven at this stage.

Other Chronic Diseases

It is well documented that a lack of sleep is associated with many poor health outcomes, including cardiovascular disease and even cancer! Our immune function also suffers from a lack of sleep making us more vulnerable to a whole host of various infections.

Typically, it is the Natural Killer cells that play a major role in our bodies to stave off and kill cancer cells in their tracks. Studies have shown that even just after a single nights deprived sleep (4 hours sleep), this led to a 70% lowering in T cell activity.

Re cancer, one of the main reasons that the risk of cancer increases exponentially with age is due to a less effective immune system, otherwise called ‘immuno-senescence’. It is therefore unsurprising to also learn that lack of sleep is even associated with an increased incidence of various cancers, including bowel, breast and prostate cancers. Increased risk of cancers has even been associated with shift work and disturbed sleep patterns, with the WHO (World Health Organisation) now categorising shift work as a probable carcinogen!

Re Glucose(sugar) Metabolism, lack of sleep has also been shown to interfere with this important energy producing metabolic pathway, making a sleep deprived person 50% less efficient at absorbing glucose and shuttling it into the cells. This in turn causes the pancreas to make more and more insulin. If this is repeated again and again, then insulin resistance can build up leading to type 2 diabetes.

In summary, studies show that a lack of sleep will cause increased loss of muscle, lower testosterone levels in men, less motile sperm, increased risk of Alzheimer’s disease, increased cardiovascular problems, type 2 diabetes and even a higher risk of a variety of cancers.

How can I improve my sleep?

The Sleep Council tells us that around a quarter of people in the UK have problems with getting a good night’s sleep regularly. Improving the quality of your sleep is possible by following the following tips:

• Avoid alcohol or caffeine near bedtime
• Avoid drinking excessive amounts of fluid in the evening
• Don’t stare into any blue light devices such as smartphones and tablets near bedtime
• Exercise every day, but not too close to bedtime
• Try getting into a routine with going to bed and getting up at the same time
• Make your bedroom as dark as possible before bedtime
• Eat a healthy, well-balanced diet with plenty of fruit and vegetables
• Avoid afternoon or evening napping
• Get up early and go to bed early-avoid sleeping in too late
• See your GP if you are having breathing problems during sleep as this can lead to sleep apnoea
• Supplement your diet to replenish vitamins you may be lacking

Can Supplements Help with Sleep?

There are essential vitamins and minerals that are important if we are to ensure that our energy-producing metabolism is at its best. However, we know from published studies (Public Health England) in the UK, that the majority of us are failing to get what we need from our diet alone.

See blog on nutritional deficiencies in our Diet

There are a variety of dietary supplements on the market both in shops, supermarkets and also on the internet.

Firstly, it should be noted that EFSA (European Food Safety Authority) have not granted any legal health claims relating to sleep enhancement to any supplement, not are they likely to in the short term. To gain such legal approval, it is up to the manufacturer to submit a large and high-cost scientific dossier to EFSA, proving via human trials, the efficacy of their particular supplement. So far sleep supplements have been unsuccessful due to lack of solid data.

Having said this, there is a variety of various scientific trials that have been performed successfully across a range of nutrients, with some evidence of efficacy across a handful of these nutrients.

L-Theanine is an extract from green tea leaves and trials do confirm some efficacy for this amino acid, though the effect is small. Associated parameters such as reduced heart rate, lowered cortisol(stress hormone), relaxation all point to L-theanine as being efficacious to some degree in these trials.

Valerian is another root extract grown in Europe and Asia, which has shown promising and worthwhile sleep enhancements across trials.

Lavender also shows some benefits to sleep quality and duration too.

5-HTP (5- hydroxy tryptophan) is a well-known sleep aid within the supplement space and again shows efficacy across many trials. The mechanism is also well established, as tryptophan is a precursor to serotonin, which in turn then biochemically becomes melatonin. Melatonin is a hormone which is secreted by the pineal gland in the brain, whose job is to apply regulate night and day sleep-wake cycles. 5 HTP is widely available, whereas melatonin is available as prescription only, at least in the UK.

GABA (gamma amino butyric acid) is another quite well-known supplemental sleep aid, again widely available. It is a neurotransmitter that blocks impulses between nerve cells in the brain, thereby having a calming effect on the nervous system. Some trials are very positive whereas others fail to demonstrate any effect.