How to use ‘sleep maths’ to get the perfect night’s rest

sleep maths illustration
sleep maths illustration
sleep maths illustration
sleep maths illustration

You’re not still suffering from bad sleep are you? Insomnia is so 2023. In 2024, there’s an app for that. Or an orthopaedic mattress. Or a light-therapy lamp...

“The sleep economy has increased dramatically in recent years,” says Dr Guy Meadows, founder and clinical director of Sleep School, an organisation that supports people struggling with sleep. In fact, it is predicted to grow steadily at 6 per cent a year and be worth a dreamy £120 billion in 2030. Some of these products have been helpful, says Meadows. Others have simply created more confusion. We are now lying awake at night, worrying about sleep solutions, and making New Year’s resolutions to get more shut-eye.

In truth, there is rarely one solution, says Meadows. No single memory foam mattress, mindfulness app or white noise machine is likely to wave a magic wand. But do not despair: “More often than not, it is the application of lots of small, daily, gentle sleep habits over time,” says Meadows. The little things add up. Regular routines, less stress and more self-compassion are, of course, key. Sleep School’s own app aims to help with this, but “your bedroom environment also plays a key role in the quality of your sleep,” he says.

“We Brits are sometimes a bit cheap about our bedding,” agrees Russell Foster, professor of circadian neuroscience at Oxford University, and author of Life Time – considered by many to be the modern sleep bible. “We forget that we’re going to spend over a third of our lives in bed, and we won’t commit to a decent mattress.” Doing so might make a world of difference to your sleep. But, as Meadows suggests, it is only part of the puzzle. Tweaking elements from temperature to ventilation, via light and noise, can also be vital, he says.

“It’s about coming up with the perfect equation for you and your own sleep needs,” says Nicola Waller, head of furniture at John Lewis. The department store will soon launch a concept they’re calling “bed maths” (though this should, surely be, “sleep sums”). It focuses on helping customers piece together the right mattress, bedding, pillow and more. This equation, she explains, will be different for a hot sleeper compared to a snorer, or a back sleeper compared to a side sleeper. So what should your own set-up look like, to ensure the best night’s sleep? You do the maths...

Menopausal and/or hot sleeper

Slatted bed + climate-control mattress + cooling pillows + wool duvets = sleep

If you find yourself cooking like boil-in-the-bag rice at night, then you might need to rethink your bed, suggests Waller. A slatted bed base will allow for more airflow than a solid divan, helping to cool you down – but there is more you can do.

There’s some good scientific data to suggest that mattresses specifically designed to transport heat away from the body can improve sleep, says Foster. “And of course, if you are menopausal and having hot flushes, you might want bedding you can remove easily and put back on again when you cool.” As with winter fashion, layers rule.

Many people think of wool as a warming fabric, says Waller, but it has natural cooling properties which can make it a great duvet choice for hot sleepers. A pillow protector is also a wise investment, she suggests. You can lose up to a litre of water at night, she points out. It’s only hygienic, then, to cover your pillow with something you can regularly remove and wash.

Partner problems

Split tension mattress + temperature-balancing linens + separate duvets = sleep

illustration of girl hogging duvet in bed
illustration of girl hogging duvet in bed

What if you need to be wrapped in blankets to sleep, and your partner throws them off? Infuriating, but not uncommon, suggests Foster. Since women tend to be smaller, and have a higher body fat to muscle ratio, they tend to lose heat more rapidly. One solution, he suggests, is to destigmatise sleeping in different rooms (something Cameron Diaz also recently advocated, though from a less scientific standpoint). Alternatively, consider sharing a bed but having separate duvets, he suggests. Different togs for different bods.

Lots of bedding brands now have a temperature-balancing range, adds Waller, including sheets that will regulate the temperatures of two differently attuned bodies at the same time. But what if your quibble is about what happens under the sheets? Split tension mattresses have two different spring tensions in one mattress, allowing one partner to sleep on a firm surface, and the other to sleep on a medium one, says Waller – especially helpful if your partner is a very different weight from you, and so requires a different degree of support.

Side sleepers

Higher-gage, firm pillow = sleep

illustration of man sleeping on side
illustration of man sleeping on side

There’s good science to show that a decent quality pillow improves sleep, says Foster. In 2018, for example, a UCLA study dug into the reasons some teenagers got better sleep than others. Their findings? It was not technology, noise or light that tipped the dial. The students who reported high satisfaction with their pillows had the best night’s sleep (waking less frequently, and showing greater brain connectivity as a result).

What constituted a perfect pillow appeared to be subjective. What we do know, however, is this: to avoid strains and pains, you want your neck to make a nice horizontal line with your spine. So if you are a side-sleeper, a pillow that is too thin will not provide enough support. One that is too fluffy, however, may also be uncomfortably claustrophobic.

Back sleepers

Lower-gage, fluffier pillow = sleep

“Back sleepers struggle to sleep when their head is either raised too high, or not supported sufficiently,” says Waller. You want to avoid arching your neck, or allowing it to sink too low. A fluffier pillow might also create a more supported, cocooned feeling.

Sleeping with a snorer

Higher-gage, firm pillow + white noise = better sleep

Sharing a bed with a snorer? There is no greater trial. But there may be hope. “People tend to snore more when they’re on their backs, so you could try a pillow that encourages them to turn onto their side,” suggests Waller.

White noise can also help to drown out the sound, or at least make it less alarming. A growing number of speakers have been designed to slip either inside or under your pillow to provide this. Sleep headphones are a good alternative – built into soft headbands to make them comfortable and secure at night.

If noise pollution of any kind is keeping you awake, “noise-cancelling devices are one of the examples where technology can actually be really helpful,” says Foster, “because it’s not low, constant droning noise that disturbs us, it’s intermittent noise.”

Night worriers

Blue colour scheme + old-fashioned alarm clock + blackout blinds = better sleep

Weighted blankets promise to soothe anxious minds and promote sleep, and sales rocketed during the pandemic. Their efficacy, however, is not entirely clear, suggests Foster. However, the impact that light has on sleep is well studied. So if you are waking, then worrying about your ability to get back to sleep, black-out blinds might be a sensible move.

Glancing at an illuminated clock-face will also raise your anxiety needlessly, he suggests, because you are likely to fixate over the exact amount of sleep you are losing as you lie awake. So consider an old-fashioned alarm clock instead of a digital one (or, worse, the clock on your phone).

If you are considering an entire bedroom redesign, some research (including one carried out by the University of Sussex in collaboration with a paper company) suggests that navy blue is the most relaxing colour.

Frequent fliers

SAD lamp + black-out blinds + eye mask + pillow spray = better sleep

If jet lag regularly knocks your circadian rhythm out of place, then blackout blinds can help “create an environment that tells your body it’s sleep time”, says Waller. SAD lamps might also help, she suggests. Originally developed to treat seasonal affective disorder with intense blasts of light, there is some evidence that they can boost alertness and wakefulness in the morning.

To bolster your sleep while travelling Waller recommends bringing an eye mask and a familiar pillow spray: “It’ll help recreate that cocooning, familiar environment you’re used to, which will help you fall asleep.”

Aches and pains

Divan bed base + orthopaedic mattress + latex pillow  + brushed-cotton bed linens = better sleep

illustration of man in bandages in bed
illustration of man in bandages in bed

If you suffer from chronic back pain, studies suggest that a medium-to-firm mattress will improve sleep quality and decrease back pain by around 50 per cent. Waller also suggests a divan frame, which will be firmer than its slatted equivalents.

Latex pillows can also help to support your head and neck, reducing pain. Meanwhile, brushed-cotton sheets and duvet covers are warm, cosy and comforting.


Body pillow + linen sheets + wool mattress topper + sleep mask = sleep

illustration of pregnant woman in bed awake while husband sleeps
illustration of pregnant woman in bed awake while husband sleeps

No need to swap your bed and mattress, says Waller (welcome news, given the price of parenting). Instead, invest in a body pillow: “In the early stages of pregnancy, it will help prevent you from turning onto your back or front. Towards the end of pregnancy, it will support the bump,” says Waller. Hormonal changes can also send your body temperature haywire, so she recommends trying breathable and natural linen sheets.

Aches and pains accompanying your journey to motherhood? If you have a firm mattress, you may need a soft topper to support and comfort you at night, in a natural and moisture-wicking material like wool. If your challenge lies in piecing together enough sleep between your constant trips to the loo, consider a sleep mask and a soothing pillow spray, to help you relax and drift off faster once you return to bed.

Poor circulation

Cosy toes duvet + electric blanket = sleep

There is no greater luxury than an electric blanket. Lay one across the end of your bed, and those cursed with cold toes can balance out their body warmth. There are also duvets on the market that have a higher tog rating in their bottom panels than at the top, keeping your feet warm without overheating the rest of your body. John Lewis, for example, sells the Ultimate Collection Dual Tog Toasty Toes Hungarian Goose Down Duvet.

Other duvets are, of course, available, but it just goes to show. There is a solution out there for every sleep problem. As long as you study hard, and get your sums right.