For some of the biggest names in politics, sleeping as few hours as possible seems to be de rigueur. Donald Trump gets by on four to five hours, while Theresa May claims she sleeps for about five or six hours a night. “There’s a lot of work to do,” she said on BBC Four’s Desert Island Discs. Since becoming prime minister, it’s believed that May has sliced an hour off her alarm clock. But should sleep deprivation really be something that’s worn as a badge of honour?

The amount we sleep impacts everything from our immune system to our memory, and therefore our ability at work. One study found that sleeping six hours per night for 14 nights, compared with regularly getting eight, produced “cognitive performance deficits equivalent to up to two nights of total sleep deprivation”. Another study found that having more kip can equate to a higher salary, with just one hour extra sleep boosting your pay packet by 4.9%. Sleep deprivation even costs the UK economy £40bn a year, according to research from Rand Europe.

Not only are you less alert when sleep deprived, but you’re less likely to make good decisions, focus on tasks or manage your mood, says Lisa Artis, PR and marketing officer for the Sleep Council. “There are dangers in being sleepy at work, especially if your job involves driving or operating any kind of machinery,” she says. “If a worker loses just one night of sleep their cognitive ability is roughly the same as being over the legal alcohol limit.”

Indeed, sleep deprivation compromises our accuracy and judgment – just like alcohol. “It affects our brain’s ability to assess risk, increasing the likelihood of us making riskier decisions than when well rested,” says Dr Guy Meadows, a sleep and insomnia specialist and founder of the Sleep School.

Sleep deprivation has even “been found to be at the heart of most major disasters including Chernobyl, Exxon Valdez and the Challenger space shuttle”, he says. An investigation into the Exxon Valdez oil spill, which saw the tanker spill more than 10m gallons of crude oil into the sea, found that the crewman piloting the ship had worked up to 18 hours before the accident.

A good night’s sleep

More, better-quality sleep is essential to a safe and healthy work environment, experts say, but how much sleep should we be aiming for? “There is no magic number, but there is a general consensus that around seven to eight hours is best,” says Artis. “Most adults require somewhere between six and nine hours in order to feel refreshed and to function well both mentally and physically.”

Sleep scientist Prof Graham Law says it’s down to each individual. “You will know how you feel. You don’t want a feeling of grogginess, nor do you want to sit staring at your screen not working. But ultimately, if you answer no to ‘is tiredness a problem for you in the day?’ then you are doing the right thing.”

However, having a good night’s sleep doesn’t always come easy. The Sleep Council found that 74% of Brits sleep less than seven hours a night.

But there are ways to get around this – an afternoon nap could be an effective way to keep focused during the day. “I truly think that modern society, which thinks napping is for lazy or old people, is going to realise that we should have a quick, short rest in the middle of the day,” Law says. “We have a circadian dip after lunchtime and a nap will mean you work better in the afternoon.” However, keep it short – about 20 minutes – as any longer you are having a full sleep. Artis also warns: “Be aware that if you experience insomnia or poor-sleep quality at night, napping might make these problems worse.”

Many of us would jump at the chance of having a snooze at work. One in five workers said they would be more willing to accept a job if napping was allowed, according to a survey by online bed retailer Time 4 Sleep. It’s not surprising then that companies such as Google and Uber are embracing employee napping, with dedicated pods installed at their offices. However, critics have questioned if such pods are actually a ploy to encourage workers to stay longer in the office and pull all-nighters.

Anis Qizilbash, founder of Mindful Sales Training, is a huge advocate of a nap. “I take a nap because when I feel tired and work is more effort than it needs to be. I curl up on the sofa or tuck into bed for 20 minutes, wearing eyeshades. It might take five minutes to fall asleep, but it’s the best 15 minutes deep sleep ever.” She says napping for more than 30 minutes makes her groggy, so she always sticks to less than 30 minutes. “After the nap I feel alert, refreshed, and clear-headed, and I also find I’m more creative.”

Aside from a siesta, Law says no caffeine before bed, exercise, a cool bedroom, and just using the bedroom for sleeping and sex can all help ensure a good night’s rest. “Then you could think about relaxation methods such as yoga and mindfulness,” he says. “Also sort the clutter – this may be physical in your environment, or may be emotional clutter, or work clutter. This will allow you to stop thinking which then leads to drifting into sleep.” And maybe encourage your employer to invest in a napping pod. Sweet dreams.

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• This article was amended on 4 August 2017 to correct the spelling of Time 4 Sleep’s name.