According to the recently published Great British Sleep Survey, more than 51% of us now struggle to get a good night's sleep.
Women are three times more likely to be affected by insomnia than men.
Evidence collected from more than 20 000 adults between March 2010 and this June shows that 93% of insomniacs report low energy levels and 83% complain of mood swings. About 77% find it hard to concentrate, 64% say they are less productive at work and 55% report relationship difficulties.
Persistent poor sleep can increase the risk of developing conditions such as diabetes, depression, high blood pressure and strokes. Research at the University of British Columbia suggests that every hour of sleep lost at night may cost us one IQ point the following day. And it is often a long-term issue: a quarter of people with insomnia have suffered from it for more than 10 years.
The United Kingdom health service spent a staggering £50-million on sleeping pills last year. But many pills have side effects and the survey's findings suggest they do not solve long-term sleep problems: 42% of people who have taken them on and off have continued to have poor sleep for more than a decade.
So, without pills, what can we do about poor sleep? Most people focus first on what Colin Espie, professor of clinical psychology and director of the University of Glasgow's sleep centre, calls "sleep hygiene": our pre-bed routine and the environment in which we try to sleep. Espie says these factors account for only 10% of sleep problems and that "most people with insomnia have better sleep hygiene than easy sleepers". But most experts concur that the following make a difference.
A dark room is important to a good sleep. Also try to avoid "blue light" less than two hours before bed: research by the Lighting Research Centre at the Rensselaer Polytechnic Institute in New York state suggests that light from laptop, tablet and cellphone screens tricks us into thinking it is daytime and keeps us alert, although this has been disputed. Bedrooms should be a comfortable temperature (about 18C), quiet and well ventilated, with comfortable beds and pillows.
Anything that stimulates the system, such as caffeine (although some studies show a cup of coffee may lengthen the time taken to drop off by just three minutes), alcohol, chocolate, tobacco, a heavy meal or strenuous exercise, will make it harder to get to sleep. Indigestible foods are best avoided; carbohydrates can promote serotonin, which aids sleep. Aim for a regular, balanced diet and no late-night excess. Twenty minutes a day of exercise will make a big difference, but avoid it just before bed.
A weekend lie-in or afternoon snooze can do more harm than good. According to research at the University of Texas Southwestern Medical Centre, "sleep debt" is best "repaid" by getting up and going to bed at your normal times rather than disrupting your body clock. Naps are recommended only if you are too exhausted to function.
"Sleep hygiene" alone will not determine whether or not we sleep well. About 90% of the battle is in the mind, which is why talking therapies and cognitive behavioural therapy are coming to be seen as perhaps the most useful solution. Espie helped to launch Sleepio, a pioneering online cognitive behavioural therapy programme. In a full clinical trial, it helped 75% of people with long-term poor sleep to get better.
So, get your head right and you will usually sleep. But how? These are Espie's top tips:
Recognise that "sleep is not a lifestyle choice; it is a biological inevitability. It is very, very powerful and we need to get it working for us: a person not sleeping well has first and foremost to allow sleep to do its work. Sleep is a process of letting go."
Most sleep problems are psychological obstacles. Like all things we should do automatically, when we try to do them we screw up. Adopt a relaxed, confident approach to sleep, not a neurotic, panic-stricken one. Recognise there's a right and a wrong kind of effort. Your role model is the "careless sleeper".
Go to sleep only when you feel sleepy and, if anything, shorten the time you try to sleep. A lot of people put good sleep beyond the achievable simply because they are so worried about not sleeping. Their sleep becomes frayed and even more broken. If I try to read a book in bed, it's never very successful because I go to bed when I'm ready to sleep. It's counterintuitive, but a shorter sleep often means a better quality of sleep.
Put the day to bed long before putting yourself to bed. "A racing mind – what happened today, what's on tomorrow? – is a huge obstacle to sleep. So take time before bed to go through the day, think about tomorrow, put things in their boxes, make a list. Set your mind at rest."
Learn to value relaxation and, if necessary, learn specific relaxation techniques. Above all, don't try too hard. But, of course, for some that is easier said than done. – © Guardian News & Media 2012