Best-selling author Dr Michael Mosley thought he'd tried everything that might improve his insomnia. Then he joined a clinical sleep trial for the three-part SBS series Australia's Sleep Revolution.
By the end of the eight-week trial, every one of the trial participants was sleeping better, Dr Mosley says, while 80 per cent of the group – including him – were sleeping a lot better.
He shares the science-backed techniques that are helping him finally get a good's night rest In the new book Four Weeks to Better Sleep.
Listen to the interview
Dr Mosley was an overworked father of four in his early 40s when he started having trouble sleeping.
"I started to wake up at three in the morning and worry about life. And that kept me awake and I often struggled to get back to sleep and it continued to be that pattern, really up until I started making well really until I completed Australia's Sleep Revolution."
Waking up around 3am is very common, says Mosley, who describes himself as "a bit of a worrier".
Making Australia's Sleep Revolution, he was surprised to find out that his "fast-moving body clock" was playing a role.
"Normally, your core body temperature should be at its lowest about four or five in the morning – that's when you're at your sleepiest. It turns out mine was [lowest] at about 1:30 in the morning, and by four or five my body would be [telling] me to get up, get ready for the day. That may be what my body was telling me but it's not what my brain really wanted.
"That was one of the things that surprised me more almost than anything else – the extent to which my core body temperature and my internal clock was out of sync with the outside world. I think that's a big part of what drives insomnia in a lot of people."
Dr Mosley now follows sleep hygiene rules "pretty rigorously" and flashes bright light into his eyes every night.
In the mornings, he finds it helpful to get up at 7am and go out for an early morning walk.
Although it's "quite tough" to action, bedtime restriction – restricting the amount of time you spend in bed – is probably the most effective method of treating insomnia, Dr Mosley says.
For a few weeks during the trial, he went to bed at 11pm and got up at 5am.
"That meant my sleep drive increased to the point where I could pretty well sleep for the night. I gradually increased the amount of time that I allowed myself in bed so I'd get up gradually later. These days it's more like 6:30 so I'm spending about 7.5 hours in bed at night but I am sleeping for about 7 hours."
For Mosley, deep breathing (especially when carried out at three in the morning) has also been "quite life-changing".
"I do that one called four-two-four [aka box breathing]. You breathe in through your nose to the count of four, hold it for two and exhale to the count of four.
"What happens is you're activating something called the parasympathetic nervous system. And that acts like a sort of braking system on your body and your brain ... Keep going for a minute or so, maybe two minutes, you'll find that a great way of falling asleep."
If you're awake in the middle of the night and breathing exercises don't work, Mosley says it's best to get yourself out of bed.
"Find a quiet corner, read a dull book, listen to some music until you feel sleepy and then you get back to bed. The reason you do that is it's about the two S's – bed should be for sleeping and sex and nothing else. You shouldn't be lying there three in the morning worrying about life."
Four Weeks to Better Sleep is designed so readers don't have to visit a sleep clinic or buy any fancy equipment, Dr Mosley says.
"Essentially I start off by telling you a lot more about sleep and what it does and some history of sleep. Then I describe how you can do some self-diagnosis in terms of what your sleep problems are likely to be. Then I describe again in some detail how things like changing your diet can have a big impact on your sleep.
"The book contains recipes, which are based around a Mediterranean diet because we know having more protein and more fibre improves sleep. But critically, it's also about when you eat. Ideally, you should try and avoid eating within a couple of hours of going to bed because your body really doesn't like having to digest food in the middle of the night.
"If you're eating sugary junk food then unfortunately and fairly obviously, that's going to lead to disruptive sleep. The same is true obviously of alcohol and caffeine, particularly taking close to bedtime."
When it comes to supplements, Mosley is "completely unconvinced" that any work for sleep, apart from a little melatonin, particularly for "3am wakers".
"In the book, I go into melatonin and how and when to use it because if you use it in the wrong way, it's just as likely to disrupt your sleep as improve it."
If you feel constantly shattered from lack of sleep, it's "really, really important" to find out if sleep apnea is at play, Mosley says.
"If you are a bit overweight. If you're getting on a little bit, you know 40s, 50s... if you're a woman after menopause, these are all classic times when you're likely to develop sleep apnea. Plus if a parent had it because there's a strong genetic component to it."
Sleep apnea – in which your tongue blocks your airways causing the brain to wake you up – is "massively underdiagnosed" in New Zealand, Dr Mosley says.
"Probably 5% of people who have sleep apnea realise they have sleep apnea. And it's really bad for your brain. It's bad for your heart. It's bad for a whole host of reasons. But also you just feel shattered, you feel awful, which is why sleep apnea is worth paying attention to and getting a diagnosis.
"It doesn't matter how much lavender you have spraying around the bedroom or whale sounds or anything like that. Unless you get sleep apnea sorted out then nothing else is going to work."
Dr Mosley says sleeping with a mandibular advancement device (MAD) – which positions the tongue inside the jaw so it can't fall back –has been "hugely effective" in helping him sleep without a CPAP machine.