Part 1: Sleep and its connection with health
However else we may differ in the ways we live our lives, one thing that is common to all of us is the need for sleep. We’ve all heard stories of people cheating their natural rhythms and ‘power napping’ throughout the day so they only need a few hours at night, (remember Margaret Thatcher and her famed four hours a night), but in reality this is very rare and most of us relish a good night’s sleep. But how many people are actually getting a regular, totally refreshing, wake-up-bright-and-breezy, 7-8 hours of solid, undisturbed sleep? Recent studies report that insomnia and disordered sleeping is suffered by around one third of the population, with insomnia being one of the most commonly reported problems in primary care. Insomnia is closely linked to a number of psychological problems, as well as a reduction in perceived general health and wellbeing. In addition, there is considerable research supporting a strong link between inadequate sleep and increased risk of cardiovascular and all-cause mortality. This may seem like a shock but when you consider how awful you feel when you’ve had just one night of bad sleep, you begin to realise how important sleep really is.
Studies have found that poor sleep quality and duration play an important role in immune and neural function at a molecular level. This can lead to the development of disease including cardiovascular disease (CVD), metabolic disorders and, as a result, reduction in lifespan. Sleep deprivation, even mild, leads to compromised brain and physical function, often manifesting as poor concentration, bad coordination or clumsiness, reduced ability to cope with everyday stress, low energy and moodiness. Quality of sleep impacts on how we perceive our health status, regardless of whether a real problem or illness is present. As a result we are more likely to take time off work, feel generally unwell and use unnecessary medication if sleep deprived. Insomnia alone accounts for over 10% of days off work after controlling for actual illness.
Most people would consider poor sleep to be when they have not had enough, but it seems that the health impact is also seen in people getting too much sleep, namely 9 hours plus. In studies comparing three durations of sleep:9 hours, on average per night, an increased risk of adverse health conditions was observed in both the ‘short’ and ‘long’ sleepers compared with the ‘average’ sleepers. Some studies, however, suggest that the optimal number of hours of sleep is specific to each person, but on the whole those who get 7-8 hours of solid, good quality sleep, each night have the lowest risk of disease and premature death. Financial and social status have not been found to be a determinant of average length of sleep, suggesting the causes of poor sleep are not linked to a particular type of lifestyle.
System shutdown: the sleep process
So, if the right length and quality of sleep is so important that even getting too much can affect our health, what goes on once we enter ‘system shutdown’? Sleep is divided into two distinct phases: REM (Rapid eye movement), which we have come to associate with dreams, and non-REM. These make up 20-25% and 75-80% of total sleep time respectively. Non-REM sleep is further divided into four stages – each representing an increasing level of depth. These phases cycle throughout a period of sleep starting with non-REM stages 1-4, followed by REM. The two phases lengthen with each cycle as a period of sleep continues.
During these phases, altered functioning of the body’s systems occurs compared with when we are awake. Brain activity, heart rate, blood pressure and respiration rate all slow down during non-REM sleep then pick up again during REM; muscle tone, however, acts in the opposite fashion, being almost normal during non-REM sleep and completely absent during REM sleep.
Scientists believe that sleep-wake cycles are regulated by the interaction of two processes: S, sleep promoting and C, maintenance of wakefulness. Process S is controlled by neurons in the brainstem responsible for turning off arousal inputs, therefore allowing the brain to shut down and ultimately fall asleep. It has been found that loss of these specific structures results in extreme insomnia. Regions of the brain responsible for sensing the state of the body also influence this process by telling the brain how full its stomach is, current psychological or emotion status and whether it’s the right time to sleep, e.g. it’s dark outside.
Process C generates and maintains wakefulness through activation of the brain’s arousal systems and a collection of neuronal inputs, which prepare nerve cells for interpretation and analysis of incoming information from all the senses. This two-process regulation of sleep is also closely linked to our circadian rhythm, a clever body clock that controls many aspects of physiology and behaviour, by direct interaction between the brain and brightness detectors in the retina. As a result, the body is able to control which systems are activated at night and make sure certain things only happen during the day. The sleep-wake process changes dramatically from birth to old age, with a general pattern towards reduced sleep efficiency as we age.
Part 2: Why we need sleep and becoming more sleep efficient
The reasons why human sleep follows these cycles, why things change so much over a lifespan and even why we need to sleep at all still baffles sleep scientists, but just stay awake for 24 hours and you’ll soon see we cannot function without it. Speculation over the years has led to the following theories as to why we need to sleep:
1) Humans have adapted for protection and energy conservation. Scientists to some extent believed that in order to survive the potential dangers of predators at night, when we are poorly equipped to cope with a threat, we adapted to crawl into a hiding place and sleep until the sun came up. It was also thought that due to poor supply of food the adaptation process forced us to go into system shutdown when we are least able to forage, therefore conserving valuable energy supplies. These theories have since been largely dismissed due to strong opposing evidence.
2) Recalibration and restoration. Based on the understanding that if we don’t sleep we become, in most cases, rather useless at carrying out daily tasks, scientists hypothesised that sleep allows our bodies to undergo a series of essential daily recalibration processes to ensure we are functioning at our optimum. These processes allow time for repair, fine tuning and rejuvenation of any system seen as not fully functioning, therefore ensuring we wake up restored and ready to face another day.
3) Brain development. Recent findings suggest that sleep correlates to changes in structure and organisation of the brain. When we are children, sleeping is essential for brain development as it is the time we process the days events and as adults, after a period of bad sleep we are less able to perform simple tasks and learn new things. This has led scientists to conclude that the quality and quantity of sleep has a huge impact on learning by affecting our attention capacity and on memory consolidation – also an essential element of the learning process.
Tips for improving shut-eye
So it’s plain to see that good quality sleep really is of vital importance not only for general wellbeing but also for health and brain development. But what can you do if you are struggling to get this essential restorative sleep? If you are someone who generally wakes up feeling sluggish, drowsy and below par and rarely refreshed, eager to face the day, here are some simple recommendations to help get you closer to finding that elusive sleep.
- Before bedtime, make sure your brain and body have had sufficient time to shut down. The areas of the brain that allow you to fall asleep are those that turn off sensory input mechanisms. If you are forcing them to remain switched on by watching TV, surfing the internet, studying, working or playing computer games until 10 minutes before you want to be asleep, your senses will be in hyper-drive, preventing you from entering a relaxed state of mind until well after you want to sleep. Opt instead for reading a book in bed, listening to a light-hearted radio station or some music.
- Switch off all bright digital screens at least half an hour before bed. If you do watch TV or use a computer before bed, try to ensure that these activities are carried out in a room other than the bedroom, as this will help your brain to associate the bedroom with rest and relaxation.
- Try to go to bed and get up at the same time every day. By getting into a routine, your body clock will be more in tune with when you need to be asleep, allowing you to feel tired at the right times, not when you need to be awake.
- Making sure your sleep environment is calm, clean and tidy will have a positive impact too. Changing the colour of your sheets to white, pale blue or any other colour you find calming and keeping your room tidy and clutter free will help create a relaxing, sleep-friendly environment.
- Light is very important too, as the brain uses this as a means to detect the time of day as an indicator for when we should be sleeping or wakeful. Try to spend a little time before bed in dim lighting, use a bedside lamp whilst getting ready for bed, to give the brain a signal it’s time to wind down.
If you are still struggling having tried all of the above, you might want to optimise the following aspects of daily life. Regular exercise will help keep you physically fit and healthy – both great aids to good sleep – but also in an age when we lead very sedentary lives we often go to bed physically alert. Some moderate to high intensity exercise most days of the week will help you burn off excess energy and even induce sleepiness, as your body prepares to recover. Make sure you are not exercising too close to bedtime, as the hormones that get you fired up and ready for action will still be active in the bloodstream, keeping you awake.
Taking a warm bath or a hot milky drink before bed are both comforting ways of telling the brain it’s time to relax. If you do have problems in sleeping make sure to avoid caffeine from about 2pm onwards, as this can linger in the blood, keeping you alert much longer than you might think. Alcohol is also a false friend when it comes to poor sleep. It may help you to fall asleep more easily but the impact it has on body temperature and growth hormone cycles means it will likely affect the quality and quantity of sleep. One drink finished an hour or more before bedtime should be optimal to help you relax in the evenings without impacting too much on sleep quality. Try not to use alcohol as an aid for sleeping as it does not provide a long-term solution and may even become a problem of its own. All of the above factors can alter your body temperature, which can have a big impact on sleep quality. Try to make sure you are cool but comfortable when you go to sleep and that the temperature in your room isn’t likely to change drastically during the night. Being too hot or too cold will keep you awake and prevent your body from shutting down adequately, thus preventing restful sleep.
Busy minds stay awake
Many of us have trouble sleeping as we feel we aren’t able to ‘switch our brains off at night’. If you are someone who has this problem, try to clear your mind of everything possible before switching the light off. You could try the following:
- Write down anything you need to remember to do in the morning or during the following day. Set alarms or reminders on your phone to make sure you don’t miss appointments. This will stop your brain from hanging onto these thoughts in an attempt to commit them to memory before you sleep.
- Keep a notepad beside the bed in case you find yourself waking up in the night with a head full of work problems or ideas, so you can write things down and fall straight back to sleep.
- Relaxation or meditation techniques can help clear your mind and allow your brain to shut down. Lie on your back with your hands by your sides and focus on one thing, e.g. the movement of air in and out of your nose and mouth, the sounds you can hear in the room or your heartbeat. Try to think only about this one thing and when your mind wanders off this course, gently return your thoughts to your chosen focus. Stay lying on your back for as long as you can or until you feel yourself dropping off, then allow your body to get comfortable and drift off.
- If you are lucky enough to have a partner who doesn’t have trouble in sleeping you could ask them to rub the tips of their fingers or finger nails over your head for a few minutes to help you relax and let go of any tension. Physical contact can be very important for relaxation and the gentle pressure and movement across your scalp will help the brain to cut out any unwanted thoughts. You might want to go one step further and ask your partner to give you a relaxing massage if you are particularly wound up. Focus on the upper back, shoulders, neck, head and face, as these are areas where most of us carry our tensions and stress. Using a lightly scented balm to reduce friction on the skin is preferable to oils as they soak in and don’t require mopping up any excess before rolling over and going to sleep. Make sure to return the favour so your better night’s sleep doesn’t result in a disgruntled partner! A regular professional massage might be a good way of unlocking some deep-rooted problems.
Sleep disorders tend to go hand in hand with psychological problems such as anxiety and depression, so make sure, if this is the root cause of your problems, to address these issues in addition to improving your sleep habits and environment.
Most importantly, stick with any changes you make. You are unlikely to see instant results, as your body needs to adjust to the new regime. Pick just one or two things to try at a time, remain positive and keep persevering. Very soon you should start to reap the benefits.
Part 3: Natural, herbal and pharmacological help
Section 2 covered all the simple things to try at home to help improve sleep quality. What if you’ve tried all of them and you still aren’t sleeping as well as you would like? Many people, at this point, feel understandably frustrated and start to search for natural, herbal and even pharmacological means to improve their sleep. Despite widespread use of nutritional, herbal and pharmacological sleep aids, there is still much conflicting evidence as to what effect, if any, these methods have on sleep and whether there might be some detrimental impact on other aspects of health as a result of taking drugs, supplements or over-the-counter pills. The following section will address the current understanding and options available to help you sleep.
Sleep and diet
Evidence very clearly supports a link between poor sleep and health related behaviour. People who regularly suffer from poor sleep are more likely to exercise less, eat higher energy-dense food and consume a greater proportion of calories from fatty and refined carbohydrate sources. In addition, fruit and vegetable consumption is reduced, meal times are more irregular and snacking more common, when compared with our ‘sleep-efficient’ peers. This not only has a negative impact on sleep quality, but can also lead to serious health problems such as metabolic disorders and obesity if left unaddressed.
So if sleep has such a big impact on what we choose to eat, can what we choose to eat have an impact on sleep? There are many well known dietary methods associated with inducing or promoting sleep – for example, a hot milky drink before bed. Milk contains melatonin, which is the hormone responsible for inducing sleepiness in response to darkness, and strong evidence exists to support the role of milk ingestion at bed time in improved sleep, even in subjects not suffering from sleep disorders. Herbal teas such as camomile are thought to have a calming effect on the brain and body, helping us to relax before bed; camomile is widely used as a natural sleep aid, with wide anecdotal, though little formal, supporting evidence. There is also some evidence linking tart/sour cherries or kiwi consumption with a reduction in symptoms of insomnia. But what about diet in general? Can what you eat on a day-to-day basis affect the length and quality of sleep and if so, then what is the optimal combination of nutrient intake to ensure restful sleep?
When looking at macronutrient content of the diet and its relationship to sleep, scientists have found a small link between protein ingestion and daytime alertness. Inclusion of proteins rich in tryptophan (the precursor to melatonin and serotonin, important for sleep quality) as part of an evening meal may be important for early morning alertness. Some studies go so far as to link pharmaceutical grade protein and the amino acid glycine supplementation with improved sleep patterns. An evening meal rich in carbohydrates but low in protein and fat has been associated with poorer sleep quality when compared with controls. Scientists were unable to decisively conclude that these results were due to the relative carbohydrate or protein and fat content of the two meal types, but this may be worth considering if you are troubled by lack of sleep and tired mornings. The type of carbohydrate may be linked to the length of time taken to fall asleep after a carbohydrate-heavy evening meal, as high glycaemic index compared with low sources were shown to reduce sleep onset. Currently the evidence supporting the role of dietary fat in sleep quality is conflicting.
Micronutrients play a crucial role in all systems of the body, with even minor deficiencies of certain vitamins and minerals having profound effects on our health and wellbeing. It’s no wonder, then, that several micronutrients have strong links with sleep health. The group B vitamins influence the roles of melatonin and therefore deficiency may impact on sleep. Vitamin B12 has been shown to have potentially beneficial effects on the sleep/wake cycle, as it plays an important role in melatonin secretion. High levels of niacin (vitamin B3) intake were found to improve sleep in insomnia sufferers as it is thought to reduce tryptophan conversion to Vitamin B3 and thus leaves more available for conversion to melatonin and serotonin.
Studies in rodents have found that oral supplementation in subjects with low baseline magnesium status improved sleep quality and quantity. In addition, one study showed that 43 elderly subjects with insomnia, given a magnesium, zinc and melatonin preparation before bedtime for eight weeks increased both their sleep time and quality. It is believed that magnesium plays a key role in pathways responsible for melatonin secretion and acts to decrease central nervous system stimulation, thus promoting sleep.
Nutrition is a complex area of study as it is very hard to clearly conclude that one particular aspect of an individual’s dietary habits is the root cause of a specific problem. There is certainly lots of evidence supporting the role of a number of dietary factors in promoting sleep quality and quantity and it is always important to remember that there is no substitute for a balanced healthy diet rich in fresh vegetables, fruit and lean protein. Avoiding refined carbohydrates and very fatty, salty and processed food should help to ensure you are eating adequate amounts of all the vital nutrients without filling up on the nutritionally ‘empty’ foods. If you are worried about deficiencies in your diet, it might be worth getting tested before trying supplementation, as a healthy diet, possibly with specific supplementary help, can often correct problems in those without more serious clinical deficiency.
Herbal and over-the-counter sleep aids
There is little hard evidence to support the usefulness of over-the-counter natural and herbal sleep remedies. Many of the natural remedies purchased by consumers address individual causes of poor sleep by aiming to reduce anxiety and stress whilst promoting relaxation. Camomile is currently the most common ingredient of herbal potions, with mixtures of valerian root, lemon balm, lavender and magnesium following close behind. Many of these are in tablet form and must be carefully considered before taking. Some of the ingredients are not supposed to be ingested in such high amounts and will likely be largely inactive, meaning that the body cannot utilise them. In addition, they may also contain a number of chemical additives to make them ingestible and digestible.
If you do want to use herbal remedies try oils and balms, or teas to reduce the potentially negative impact of possibly ingesting high levels of poor grade ingredients. Many over-the-counter sleep therapies use the same key ingredient as cold and allergy medicines, antihistamine, as this is generally associated with causing drowsiness. Even if you are experiencing benefits these are pharmaceutical products designed to treat quite different problems and may in the long term impact on your health.
There are a number of pharmaceutical products currently available to help address sleep problems and these are best discussed with your GP, as the reasons behind poor sleep will likely be different for everyone. If you have reached the point where pharmaceuticals seem like your only option, it is important to do a little reading around the subject before you consult your GP so you can have a proper discussion about your options. Making sure you are comfortable and involved in the choice of drugs you may be taking will give you the best possible starting point for successful therapy.
You may also wish to discuss other options available on the NHS. Cognitive behavioural therapy has been shown in recent studies to be more effective than any single component treatment in helping insomniacs. It is not yet understood which elements of CBT are most effective as this is not a standardised practice, but CBT may provide a much more effective and long-term solution to sleep disorders. Your GP may even be able to refer you to a complementary health specialist who will help you address individual concerns relating to your sleep problems.
Sophie Tully– a nutrition, fitness and health scientist – started her consultancy business thanks to the help and support of many inspiring and thought-provoking people. Her passion for fitness and nutrition, deepened by her biomedical science and cancer research background, led to the creation of Sophie Tully – Total Health Consulting, to promote ‘Total Health’ to the public. Sophie’s mission is to show people that ‘optimal health’ is not just being disease-free. It is about living a long and happy life without reliance on medication, or suffering ongoing illness. ‘Health’ results from a delicate balance of nutrition, physical fitness and mental wellbeing, specific to each of us. Each aspect is equally important and reliant on the other two. One element alone can shift the balance and impact on health. Using simple and effective, hands-on methods, Sophie Tully – Total Health Consulting will help clients discover their unique ‘health’ profile and provide simple solutions to achieve vitality.
Sophie Tully BSc, MSc, REPs Level 3.