How sleep affects work performance: what the research shows

Sleep affects work performance through attention, reaction time and mistakes. Lab studies show that even moderate sleep loss, like a few weeks of 6-hour nights, slows people down and makes them less accurate, often without them noticing. Field studies and economic estimates show the same thing at work: more errors, lost days and real costs. Snoring belongs in this picture too, because broken sleep and daytime sleepiness often go together.

How does lack of sleep affect work performance?

Lack of sleep makes you slower, less focused and more error-prone at work. The National Heart, Lung, and Blood Institute (NHLBI) says sleep deficiency can cause problems with learning, focusing and reacting, and can make it harder to make decisions, solve problems and remember things. It says people who are sleep deficient are less productive at work and school, take longer to finish tasks, have slower reaction times and make more mistakes.

The NHLBI also points out that this isn't just about desk jobs. It lists healthcare workers, pilots, students, lawyers, mechanics and assembly line workers among the people whose work suffers from sleep deficiency.

Can you get used to sleeping 6 hours a night?

You may feel used to it, but your performance keeps sliding. In a well-known 2003 study in Sleep, researchers at the University of Pennsylvania kept 48 healthy adults aged 21 to 38 in a lab. Some were allowed 8, 6 or 4 hours in bed a night for 14 nights in a row, and others had no sleep for 3 nights.

Those limited to 4 or 6 hours got steadily worse on every thinking test, and the deficits built up night after night. By the end, 6 hours or less a night had produced deficits equal to up to 2 nights of total sleep deprivation.

The most important finding for anyone at work was about self-awareness. People's own sleepiness ratings rose at first, then only crept up a little more, and didn't clearly separate the 6-hour and 4-hour groups. The authors concluded that the participants were largely unaware of their growing deficits. In other words, "I'm fine on six hours" is exactly what someone with those deficits would say. Our guide to how much sleep adults need covers the recommended 7 hours or more.

Is being tired at work like being drunk?

Being tired can impair performance about as much as being mildly drunk. In a 2000 study in Occupational and Environmental Medicine, Australian researchers tested 39 people, 30 from the transport industry and 9 from the army, over 28 hours without sleep and again after measured doses of alcohol.

After 17 to 19 hours awake, which for these participants was 10:30pm to 1am, performance on some tests was equal to or worse than at a blood alcohol concentration of 0.05%. Response speeds were up to 50% slower on some tests. After longer without sleep, performance reached the level seen at about 0.1%, the highest alcohol dose given.

Seventeen hours isn't extreme. It's a 6am start and a late evening. The NHLBI makes a similar point about driving, saying studies show sleep deficiency harms driving ability as much as or more than being drunk. Our article on sleep apnea and driving looks at the road risks in more detail.

Does tiredness cause mistakes at work?

Tiredness causes more mistakes at work, and one of the clearest examples comes from hospitals. In a 2004 randomized study in the New England Journal of Medicine, researchers compared interns working a traditional schedule, with extended shifts of 24 hours or more every other shift, against a schedule that cut out those long shifts and reduced weekly hours.

On the traditional schedule, interns made 35.9% more serious medical errors, including 20.8% more serious medication errors. They also made 5.6 times as many serious diagnostic errors. The authors concluded that eliminating extended shifts could reduce serious errors in intensive care.

Most jobs don't involve 24-hour shifts, but the lesson carries over. When tired people do complex work, the mistakes add up, and some of them are the kind nobody catches in time.

How much productivity does poor sleep cost?

Poor sleep costs a lot of productivity, both for individuals and employers. A 2017 analysis by RAND Europe, published in RAND Health Quarterly, estimated that workers who sleep less than six hours a night lose about 6 more working days a year to absence or working below par than workers who sleep seven to nine hours. Those sleeping six to seven hours lose about 3.7 more days.

Across the US economy, the report estimated losses of between $280 billion and $411 billion a year from insufficient sleep, depending on the scenario. It also found that people sleeping under six hours had a 13% higher mortality risk than those sleeping seven to nine hours.

A 2010 study in the Journal of Occupational and Environmental Medicine surveyed 4,188 employees at four US companies. People with insomnia or insufficient sleep had significantly worse productivity, performance and safety outcomes than good sleepers, and the authors estimated fatigue-related productivity losses at $1,967 per employee a year.

These are estimates built on surveys and models, so treat the exact figures as rough. The direction is consistent across studies, though: short sleep shows up at work.

Can snoring make you tired at work?

Snoring can make you tired at work, especially when it's heavy or linked to sleep apnea. In a 1996 study in Chest, Swedish researchers surveyed men aged 30 to 64 from the general population and men referred to a sleep lab.

Compared with non-snoring men in the general population, snorers in the general population were four times as likely to report excessive daytime sleepiness at work. Snorers referred to the sleep clinic were 20 times as likely, and men with obstructive sleep apnea 40 times as likely. The clinic snorers and the men with sleep apnea also reported more difficulty concentrating, learning new tasks and doing monotonous tasks. The authors concluded that snoring is not merely a nuisance.

The study relied on self-reports, so it shows a link rather than proof that snoring causes poor work. But it fits with what we know about broken sleep, and our guide to snoring and sleep deprivation explains how the two can feed each other. It's also a reminder that a partner's snoring can cost the partner sleep and focus too.

What can you do to sleep better for work?

The most useful step is to protect enough sleep on most nights. The NHLBI says that with enough sleep each night, you may find you're happier and more productive during the day. Its healthy sleep habits include:

• Going to bed and waking up at the same time every day, keeping weekends within about an hour of weekdays
• Using the hour before bed for quiet time, away from intense exercise and bright screens
• Avoiding heavy meals and alcohol close to bedtime
• Avoiding caffeine later in the day, since its effects can last up to 8 hours
• Keeping the bedroom quiet, cool and dark
• Keeping naps to no more than 20 minutes

For shift workers, the NHLBI suggests keeping lights bright at work, limiting caffeine to the first part of a shift and blocking light and sound in the bedroom for daytime sleep. Our guides to napping, caffeine and sleep and mouth tape for shift workers go further.

If snoring is breaking up your nights, the NHS suggests side sleeping, losing weight if you're overweight, not smoking and not drinking too much alcohol. It says nasal strips or dilators can help when the nose is blocked or narrow, and devices that keep the mouth closed can help when it falls open. For snoring through an open mouth or a stuffy nose, some people try the Titan Sleep System, which pairs nasal strips with mouth tape. Check you can breathe comfortably through your nose with the nose test first. We don't recommend mouth tape for children.

When should you see a doctor about tiredness at work?

You should see a doctor if you're sleepy at work despite giving yourself enough time in bed, or if your snoring comes with signs of sleep apnea. The NHS says to see a GP if you feel sleepy during the day, your breathing stops and starts while you sleep, or you make gasping or choking noises, which can be signs of sleep apnea.

Nodding off while driving, a nose that's always blocked, or tiredness that doesn't lift after a few good nights are all worth raising too. If you're pregnant, ask a clinician before trying any snoring product. Our guides to waking up tired and sleep apnea warning signs can help you work out what to mention.

Our pick (paid partner): Titan Sleep System

If snoring is chipping away at your sleep before a workday, our pick is the Titan Sleep System. We haven't tested or ranked products ourselves, and Titan's products weren't used in any of the studies above; this is our recommendation, not a proven fix for tiredness.

Titan says the system combines TitanAir Nasal Strips and Titan Bamboo Silk Mouth Tape as one nightly routine. It describes the strips as drug-free external nasal dilators with flexible spring-loaded bands, worn just above the flare of the nostrils, and the tape as a bamboo silk strip worn horizontally across the lips. Titan suggests 20 to 30 minutes of daytime practice with the tape before the first night.

Titan says every batch is third-party tested and certified PFAS-free, and its 30-night guarantee refunds you if your sleep isn't better after 30 nights. That's long enough to see whether the system fits your routine on work nights.

Read next

• Does lack of sleep make snoring worse?
• How much sleep do adults need?
• Why do I wake up tired after a full night's sleep?

* This content is for informational and educational purposes only and is not medical advice. It is not intended to diagnose, treat, cure or prevent any disease or health condition. Talk to a qualified healthcare provider about your health.