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Knowledge is power
Key restorative processes take place while we are asleep, yet about one in five adults in the UK, and a third of those in the US, fail to get the seven to nine hours recommended for those aged 18-64.
Sleep deprivation has been linked to a long list of health problems, including type 2 diabetes, cardiovascular disease, depression and obesity.
Sleep tracking tech can help you work out if you are failing to give your body time to recover at night. Devices and apps that monitor only movement are less accurate than those that also track heart rate and breathing patterns.
Regular rules
It is not, however, all about duration. Our bodies do different things during different sleep phases, which are characterised by different brainwave patterns. REM sleep has been linked to learning and memory, while growth hormone is released during deep sleep.
One of the best ways to boost sleep quality is to maintain regular sleep times. A US study published last year found that students with irregular sleep patterns get lower academic grades.
Mind the nap
What did Albert Einstein, Margaret Thatcher and Salvador Dalí have in common? They were all enthusiastic nappers. Sleeping for 10-20 minutes after lunch can be restorative, although longer naps, especially in the late afternoon or evening, can undermine night-time sleep.
Disruptive drinking
Many believe a nightcap improves sleep. A 2013 review of 27 previous studies showed alcohol can indeed help people fall asleep more quickly, but also that it reduces REM sleep. That helps explain why you may feel drowsy and lack focus the morning after.
Booze also disturbs sleep by increasing urine production, making you need the bathroom at night. Caffeine, meanwhile, blocks the build up of sleep-inducing chemicals in the brain.
Research suggests leaving at least six hours between your last coffee and bedtime, although the time it takes to break down down varies from person to person.
The dark side of light
Body clocks in almost every cell in the human body use signals about light levels to control fluctuations in things such as hormone levels, temperature and metabolism.
Studies have shown that melatonin is released earlier and sleep duration is longer in societies that live without electric light. Candlelight may not be practical, but dimming bright lights in the run up to bedtime helps your body prepare for sleep. Using tablets, phones and televisions late at night does the opposite.
Do sweat it
Research has shown that working out can boost sleep. A review of 34 studies involving almost 2,000 participants found exercise shortens the time it takes to nod off and improves sleep duration and quality.
However, Japanese researchers found that vigorous running an hour before bedtime cuts sleep length, while moderate exercise does not.
“Regular exercise during the day or evening is a great way to improve sleep, but within two hours of bedtime it releases hormones that can lengthen the time needed to get to sleep,” says Shadab Rahman, a sleep researcher at Harvard Medical School in Boston, Massachusetts.
Make a sleep sanctuary
Ensure your mattress and pillows are comfortable and supportive. If you are sharing, you are likely to sleep better in a 1.8 metre-wide super king than a 1.4 metre-wide double. Thick curtains or blackout blinds can also help.
Body temperature drops during sleep, so 16-18C is about right. Keep your bedroom clean and clutter-free. Soothing scents may put you in the right mood for a good night’s sleep.
(THE GUARDIAN)
