As the benefits of sleep for physical and mental health continue to pile up, we've become obsessed with whether we're getting enough.
We've enlisted the help of a group of experts to help reveal how to improve the quality of your slumber, whatever your age.
Dr Neil Stanley, an independent sleep researcher and author of the book How To Sleep Well suggests anxiety, burning the candle at both ends and technology use are likely to be the biggest sleep disrupters at this age. "Limit social media late at night and buy an old-fashioned alarm clock – ideally, leave your phone out of the bedroom altogether," he says.
A Stanford University study from 2011 found even the short bursts of light from a message or notification can still be enough to disturb your bodyclock.
"People under 27 are more likely to be night owls, which can be a problem when they enter the workplace," adds James Wilson, a sleep behaviour expert who has worked with the Royal Society for Public Health. "Simply going to bed earlier won't help – don't force yourself to be in bed by 10 or 11. Instead, focus on quality over quantity and on establishing a wind-down routine at least an hour before you would ideally want to fall asleep.
"And if you're watching TV before bed, make it funny or trashy, rather than a cliffhanger."
"This is when work, financial stress and raising a family all kick in," says Dr Stanley.
If you're lying awake, brain whirring, the key thing – rather than attempting any particular exercise or counting sheep – is to stop actively trying to sleep.
"Avoid getting into that mindset of counting how many hours you've got left before you need to be up, worrying about how tired you'll be," says Wilson. "Instead, try thinking about a time you had little or no sleep, but managed to perform fine. Reassure yourself – and you're much more likely to calm your brain so sleep can happen."
Pregnancy can bring insomnia and, as many as one in four pregnant women are affected by restless legs syndrome, a neurological disorder causing an uncontrollable urge to move the legs. This stops people falling asleep or wakes them in the night.
"Low iron is a common trigger and supplements can treat it," says Dr Guy Leschziner, a sleep physician. "So if you're pregnant – or if you have particularly heavy periods – ask your GP to check."
Of course, the broken nights really begin when baby arrives, and a disturbed night's sleep leaves you feeling as bad as an extremely short one – a 2014 study by Tel Aviv University found that women who slept for eight hours but were woken four times were as groggy and tired as women who'd slept for just four hours.
"Once a child gets past feeding, my advice is to take turns on night time duties," says Stanley. "Agree who's going to get up if a child wakes, while the other person sleeps through – with ear plugs in, if needs be."
"If you're snoring, feeling tired in the day, or waking yourself up choking or gasping this could point to sleep apnoea," says Dr Leschziner. "The first thing to try is weight loss, as that often improves it."
It can also be treated with a continuous positive airway pressure (CPAP) device – a small pump and breathing mask to keep the airway open.
As children start to fly the nest, leaving you with a spare bedroom, Dr Stanley suggests a "sleep divorce": separate beds, or even bedrooms.
"It's got nothing to do with the strength of your relationship," he says. "It's just pragmatic. We know from research that the majority of sleep disturbance is down to your bed partner, whether it's physical movement or the noises they make."
During menopause, hot flushes are a common problem at night, "as to fall asleep you need to lose one degree of body heat", explains Stanley. "So avoid doing anything that raises body temperature at night: wear cotton pyjamas, don't eat late or drink alcohol or exercise in the evening."
Sleep practitioner Wilson adds: "People in midlife are often sold memory foam mattresses on the basis that they're better for aches and pains, but they are not great for temperature regulation. You'd be better off with one with more breathable, natural fillings. Likewise, look for a duvet made with bamboo or alpaca fleece."
For both men and women, sleep may be disturbed at this age by trips to the loo. "Getting up once in the night is perfectly natural," says Stanley. "But more than that and it could be down to something more severe – a prostate issue, for example – so see your GP."
He advises avoiding alcohol, which stimulates the bladder, or lots of fluid in the evening. "But make sure you have water to sip to avoid getting dehydrated as that can also wake you up."
It's a myth that we need less sleep as we age, according to Leschziner. "Older people probably need just as much as younger adults, but they're less good at achieving it," he says.
REM sleep behaviour disorders – where people act out their dreams at night, thrashing around and kicking – can be a problem at this age, particularly for men, says Leschziner.
"It can be treated with medication and can sometimes be a precursor to other neurological disorders, including Parkinson's and Lewy body dementia, so don't just live with it."
Wilson says retirement can also trigger problems. "For a lot of people, their job gives them their clock. Things you might have done when you were working, whether it was watching the news right before bed, drinking alcohol or a coffee late in the day, might start to be more of a problem because you're no longer as physically and mentally tired. Getting into the habit of late nights and lie-ins can confuse the body clock."
Drugs for age-related problems – such as pain medication and PPIs for acid reflux – can interfere with sleep, adds Stanley: "Have a conversation with your GP or consultant, as there may be alternatives."
"Unfortunately, insomnia in this age group is very common," says Leschziner. "As we get older, the brain is less good at maintaining sleep."
We also spend less time in REM or dreaming sleep, which is the most restorative type, says Stanley. "This means even if you get the same amount of sleep you always have, you're unlikely to feel as refreshed as you did."
Cognitive behavioural therapy for insomnia –CBTi – is highly effective and should be the first-line treatment, rather than drugs, says Leschziner.
Here, a therapist works with you to change attitudes to sleep and introduce a strict routine.
Another common problem is wanting to get up and go to bed early, he says. "This is a normal shift... that seems to happen over 70, but it can become extreme, meaning waking up at 3am."
Daylight is key to keeping our internal clock in sync with the 24-hour day, so spending time outside may help. "My main advice is don't assume that poor sleep is just part of the ageing process and that nothing can be done," says Leschziner.