Sleep problems are not just tiring and frustrating, they can also cause health problems, raising the risk of heart disease and stroke, according to a study recently published in the European Heart Journal.
So what are the causes of nightmares, teeth-grinding, restlessness and early waking? There are 89 different sleep disorders.
And here, with the help of experts, the Daily Mail examines ten of the most common and explains how to tackle them.
Tossing and turning
Likely cause: You’re probably too hot.
"Our bodies follow a strong natural rhythm, rising in temperature through the day and falling overnight," explains Dr Neil Stanley, a sleep expert. "At around 3am we have the biggest dip and anything that makes it difficult for us to lose heat at that point will cause disturbed sleep."
One problem is central heating. "Although people set their central heating [or cooling] to 21 degrees because that’s comfortably warm [or cold], our bedroom feels very hot [or cold] and we become restless, moving around to try and cool down [or warm up]."
Women also tend to be more restless at night during menopause and their menstrual cycle because their body temperature rises.
What you can do: "The temperature under the covers should be around 29 degrees," says Dr Stanley. "Given enough time you will heat your bed up to the right temperature because you are always burning calories, which generates heat. On a cold night your body has to work harder, so people use electric blankets or hot-water bottles - but you can overheat your bed.
"Make sure the bedroom is about 16 degrees because you need to lose temperature out of your head."
So let your room cool by turning the heating off in the evening or opening a window.
Grogginess on waking
Likely cause: A change of routine or oversleeping.
"The body craves regularity and wants to get up at the same time every day. It prepares for waking an hour beforehand," says Dr Stanley. "But it can only prepare if it knows when you’re going to get up. So if you usually wake up at 7am during the week, then at 6am your body sets the wheels in motion so you can leap out of bed."
Our natural body clock ensures hormone production is timed for waking. For example, an anti-diuretic hormone rises during the night to control urine production so your sleep isn’t disturbed by needing to go to the loo.
Your gastric juices kick-start your appetite in the morning, adds Professor Kevin Morgan, of the Sleep Research Centre at Loughborough University. But if your routine is disturbed, for instance because you lie in at the weekend, your body has to catch up on all this when you wake. The same happens on a Monday morning after a sleep-heavy weekend as the early start isn’t expected.
What you can do: The solution is as simple as sticking to a pattern and not sleeping in at weekends. "This will help synchronise with your body’s natural rhythms and also prevent the feeling of 'sleep drunkenness', where you over sleep and don’t feel good afterwards," says Prof Morgan.
Walking/talking in your sleep
Likely cause: Alcohol, medication, genetics or having something on your mind can all trigger these night time activities, known as parasomnia. "Everyone is capable of sleepwalking or talking," explains Dr Stanley.
"The conscious part of your brain can be deeply asleep while other bits, such as the area controlling movement and navigation, are still awake."
The problem can run in families, but it can also be triggered in anyone when sleep is partially disturbed, meaning part of their brain is awake.
One trigger is alcohol, which lightens sleep. Parasomnia is also common in children as their nervous system is still developing. It can also be brought on by medications, such as some antidepressants, or by different drugs interacting.
What you can do: Some parasomnias, such as talking, are often harmless. Others, such as having sex while asleep (most prevalent in young men) may be more problematic. Sleep- walking can be especially dangerous.
The advice is to try to work out the triggers which disturb full sleep (such as alcohol), check side-effects of medication with your GP and check if the problem runs in your family.
Likely cause: If you’ve had sufficient sleep, tiredness may be a result of weight gain (leading to sleep apnoea) or anxiety, which disrupt sleep without you realising it. "Sleep apnoea is a prevalent condition which affects 2 to 4 per cent of the population,’ says sleep nurse Rebecca Mullins. ‘It is common in the overweight, particularly men with large collar sizes."
As they sleep, sufferers’ airways start to collapse and they can stop breathing for anything from ten to 60 seconds. Their oxygen levels drop so low the brain wakes them and they start breathing again with a snore.
"Sufferers are not usually aware of the problem, but they don’t get refreshing sleep," says Mullins.
Another cause is anxiety. Dr Stanley says: "This makes sleep lighter and reduces the amount of deep sleep, the most restful part. Some people accept feeling sleepy during the day as being their natural state, but nothing could be further from the truth - sleepiness isn’t natural.
"If you’ve had a good night’s sleep you should feel brilliant. Unexplained tiredness during the day is always indicative of something." Other causes are chronic disease and teeth grinding.
What you can do: "If week after week you feel sleepy, then something is going on you need to look at," says Dr Stanley, who suggests speaking to your doctor.
Waking in the night
Likely cause: Intermittent waking without obvious cause is probably due to changes in your environment, stress or age. "From an evolutionary point of view, you could only sleep well if you felt safe and secure," says Dr Stanley. "So anything that stops this will disturb your sleep."
We sleep in cycles and wake very briefly at the end of each cycle, but usually only vaguely recollect this.
However, if you have something on your mind or are attentive to the environment, you will become more awake at that point.
Also, as we get older we wake up more easily. "Throughout adulthood your sleep becomes progressively lighter and more fragmented," says Prof Morgan. "This is because of changes in the nervous system and hormones."
What can you do: Rebecca Mullins says: "Avoid drinks as these fill the bladder. Don’t eat late as your body will still be digesting."
Waking too early
Likely cause: Depression-induced insomnia or your environment are the usual triggers. "Everyone thinks insomnia is not being able to fall asleep, but there are three types - not being able to fall asleep, waking up and waking too early," says Dr Stanley. "The latter is one of the classic signs of depression, though no one knows why." Changes in your environment can also wake you too early, as we wake easily in the morning anyway as sleep becomes lighter.
"You almost certainly won’t wake up for the first three hours of night as you are deeply asleep," says Dr Stanley. "But later sleep is much lighter and more prone to be disturbed by noises."
What you can do: "The big caveat is that if you feel fine during the day then whatever’s happening isn’t a problem," says Dr Stanley. If you think the issue is insomnia, speak to your doctor.
Likely cause: Known as bruxism, teeth-grinding varies from jaw clenching to ferocious grinding that wears teeth down to stumps. It is usually due to genetics or stress. "There’s nothing serious underlying teeth grinding," says Dr Stanley. "Though it can be caused by stress, it is often just due to genetics.’
What you can do: "Treatment is important, as people who grind their teeth have dental problems but also tension headaches," says Dr Stanley.
Usual treatment is a gum shield, though some people grind through these. If teeth-grinding is caused by stress, then the cause should be addressed.
Likely cause: Stress may be a factor, but otherwise they are a random occurrence. "Nightmares are luck of the draw," says Dr Stanley. "We all dream four or five times a night, but only remember them if we wake up during or just after them. So we are all probably having disturbing dreams and just not remembering them."
What you can do:People often associate nightmares with stress, which then makes them more anxious. "If you’re stressed and have a scary dream, you put them together and everything seems worse," says Dr Stanley.
Although stress can cause you to wake up more, remember we all have bad dreams all the time. Try to improve your sleep so you wake up less often.
Sleeping too much
Likely cause: A common cause of hypersomnia is disease. "Lots of people with long-term conditions tend to sleep longer," says Professor Francesco Cappuccio, a sleep expert at the University of Warwick. "It is a marker of ill health."
This also occurs in the chronic stage of long-term depression (while the early stages are characterised by insomnia).
What you can do: Tell your doctor. "Long sleep could be a marker for your GP," says Prof Cappuccio. "Unfortunately, doctors never ask how many hours you sleep - but problems can be picked up from that. If someone sleeps too much, they may have a health problem."
Though we all have our own sleep need, you should take notice if you’re sleeping significantly more over a prolonged period, napping during the day or have trouble waking up.
Can’t sleep until late
Likely cause: If you find you don’t want to go to bed until very late at night and you then struggle to get up in the morning, this could be due to a late natural body clock.
"Everyone has an internal biological clock," says Prof Cappuccio. "But this clock is not exactly 24 hours - it is between 23 and 25, which can make us morning or night people."
People with a late clock have the propensity to go to bed a bit later every day. However, this internal timing interacts with external cues, such as light, to synchronise with the day.
But left without these clues, for instance bright light at night, you would become mismatched with the day, says Prof Cappuccio.
"There is also another sleep/wake cycle regulated by light," he adds. "Melatonin is a hormone that sends you to sleep and this increases when the brain perceives that it is night. When it’s daylight, melatonin is shut down and we wake up."
However, for some people getting up late or early is simply learned behaviour that can be changed.
What you can do: Turn down main lights before bed and use a lamp. If possible, let daylight wake you.
- All pictures used for illustrative purposes only