A Guide to Shift Work Sleep Disorder

When your schedule has you working hours that don’t fit the typical 9-to-5 grind, you can feel like you’re living in a different time zone. More importantly, the constant battle between your work hours and your internal clock can impact your health and well-being, sometimes leading to a condition called shift work sleep disorder (SWSD), or shift work disorder for short. Just ask any of the nearly 24 million Americans who power through non-traditional shifts, keeping our hospitals running, our streets safe, and those late-night pizza cravings satisfied. (1) Shift work sleep disorder is a real thing, and we’re here to talk about what it means and how to get your sleep back on track.

Note: The content on Sleepopolis is meant to be informative in nature, but it shouldn’t be taken as medical advice, and it shouldn’t take the place of medical advice and supervision from a trained professional. If you feel you may be suffering from any sleep disorder or medical condition, please see your healthcare provider immediately. Additionally, restrictions and regulations on supplements may vary by location. If you ever have any questions or concerns about a product you’re using, contact your doctor.

Long Story Short

Shift work sleep disorder, also known as night shift fatigue syndrome, is a circadian rhythm sleep disorder caused by working irregular hours, affecting an estimated 27 percent of shift workers.
Shift workers account for approximately 25 percent of the adult workforce.
Shift work and night work are considered to be the most harmful schedules for workers.
Working night shifts for 10 or more years raises the risk of heart disease by 37 percent compared to working daytime shifts.
Night workers face a 42 percent higher risk of depression compared to those with daytime schedules.

What Is Shift Work Sleep Disorder?

Shift work sleep disorder occurs when you have trouble adjusting to your sleep and wake times because of your work schedule. (2) You might picture someone working the graveyard shift, but shift work disorder affects anyone working non-traditional hours, whether that’s nights, early mornings, rotating shifts, or any schedule outside the typical 9-to-5. (2)

This type of work schedule often forces you to sleep at a time during the day that clashes with your body’s circadian rhythms, Eric Olson, M.D., pulmonologist and sleep medicine specialist at Mayo Clinic and president of the American Academy of Sleep Medicine, tells Sleepopolis. (3)

In fact, shift work disorder is a type of circadian rhythm disorder. (4) (5) Think of your circadian rhythm as your internal timekeeper, following a 24-hour schedule based on daylight. When it’s dark, your body releases melatonin (the sleep hormone) to help you sleep. (6)

“When an individual is experiencing a shift work disorder, their body may produce melatonin when they need to be alert and awake at their job,” Olson says. As a result, your body’s sleep signals come at the wrong times, making it hard to stay alert at work and sleep well at home.

This mismatch can also cause both short-term and long-term issues. You might experience insomnia (trouble falling asleep or staying asleep), excessive sleepiness during work, fatigue, and more. (4) Over time, shift work disorder can affect your immune system and increase your risk of heart disease and obesity. (7) We’ll dive deeper into the symptoms below.

Examples of Shift Work Jobs

What is shift work? If your workday happens outside the typical 9-to-5 schedule, chances are you’re doing shift work. This type of work schedule includes: (7) (8)

Night shifts (graveyard or third shift): Working usually during the night, for example, between 11 p.m. and 7 a.m.
Evening shifts (swing or second shift): Usually starting your work shift anytime after noon, such as between 3 p.m. to 11 p.m.
Early morning shifts: Starting before the sun rises
Rotating shifts: Alternating between different shift schedules

Here are some common shift work jobs:

Healthcare workers (nurses, doctors, paramedics, and other medical staff)
Law enforcement and emergency responders
Manufacturing and factory workers
Transportation workers (truck drivers, pilots)
Hospitality workers (hotels, restaurants)
Retail employees
Security guards
Power plant operators
Call center representatives

Shift Work Sleep Disorder Symptoms

If you’re dealing with shift work sleep disorder, there’s usually more going on than just feeling tired.

“The sleep disturbance leads to increased sleepiness and/or insomnia,” Brittney Jones, PsyD, a licensed clinical psychologist and board-certified insomnia specialist, tells Sleepopolis. But the impact goes way beyond sleep issues.

Common shift work sleep disorder symptoms include: (7) (9) (10)

Insomnia (trouble falling asleep when you need to, even when you’re exhausted!)
Waking up too early or frequently during your sleep time
Excessive sleepiness during work hours
Difficulty staying alert during your shift
Headaches
Brain fog and trouble concentrating
Memory problems
Decreased energy
Making more mistakes at work
Feeling irritable or moody
Increased stress levels

There’s more: these sleep disruptions can impact your work performance and your social life, Jones explains. You might experience relationship struggles and feel isolated from loved ones. (11) And it can be hard to be your best self when you’re constantly fighting your body’s natural sleep rhythm.

If you’re nodding along to these symptoms, it’s worth talking to a healthcare provider or sleep specialist. In the meantime, stick around. We’ll cover some practical ways to manage these symptoms and help you get the quality sleep you deserve.

What Causes Shift Work Disorder?

Your body’s circadian rhythm has a straightforward job: to keep you awake during daylight and help you sleep when it’s dark at night. (12) When you work non-traditional hours, like nights or rotating shifts, you’re asking your body to go against its natural design. This means working during times your body expects to rest, and when it can’t adapt, shift work disorder may develop.

“Shift work sleep disorder is fundamentally caused by missing sleep at night,” Alex Dimitriu, M.D., double board-certified in psychiatry and sleep medicine, tells Sleepopolis. The more your schedule differs from normal nighttime sleep, the harder it gets, especially if your shifts keep changing, he explains. (4) For example, working an evening shift might be more manageable than an overnight shift or having your schedule flip-flop between day and night shifts every few days. (4)

Several factors can make you more likely to develop shift work disorder:

Age: People over age 50 may have a harder time adapting to shift work, and they may struggle more with consecutive night shifts. (13) (14)
Gender: Insomnia tends to be more common in women who do shift work, a review of studies found. (15) The researchers believe this is possibly due to higher rates of anxiety and depression, plus the added challenge of juggling work with household responsibilities. (15)
Shift type: Night shifts and rotating schedules are particularly tough on your body, Dimitriu notes. (3) Only about 1 in 4 night shift workers fully adapt to their schedule, and even years after quitting night work, some people still struggle with sleep issues. (4)
Sleep patterns: Your natural tendency to be either a “morning lark” or a “night owl” matters too. “Night owls may find it easier to adjust to an evening shift than a morning shift, and vice versa with an early bird,” Olson says. (7)

Still, not everyone who works non-traditional hours develops shift work disorder. (7)

Shift Work Sleep Statistics

Remember those nearly 24 million Americans we mentioned who work non-traditional shifts? Let’s look at what research tells us about shift work’s impact:

Around 25 percent of the adult workforce are shift workers. (2)
Night workers are 42 percent more likely to experience depression compared to those with daytime schedules. (4)
One study found that 51.1 percent of shift workers have at least one sleep disorder. (4)
An estimated 27 percent of shift workers experience sleep problems that develop into shift work disorder. (4)
For every five years of night work, the risk for breast cancer increases by 3.3 percent. (3)
Working night shifts for 10 or more years raises the risk of heart disease by 37 percent compared to working daytime shifts. (16)
Shift workers are nearly three times more likely to be involved in workplace accidents due to fatigue and cognitive impairment. (2)

How Is Shift Work Sleep Disorder Diagnosed?

You can start with a self-assessment. Olson suggests asking yourself these questions:

Do you have a schedule that requires you to work when you would normally sleep?
Do you have trouble sleeping, or are you severely tired due to your work schedule?
Have you had this work-related sleep problem for at least one month?
Does this problem hurt your social, family, or work life?

If you answered yes to these questions, it’s time to talk to a sleep specialist. “People with SWSD usually see a healthcare provider to have this condition diagnosed,” Jones explains. You’ll likely be asked to keep a sleep log for about two weeks — tracking when you sleep, how long it takes to fall asleep, and how refreshed you feel when you wake up. (17)

Healthcare providers will use this sleep log to confirm that your sleep troubles are connected to your work schedule and have been going on for at least three months, Jane Dyonzak, Ph.D, a licensed clinical psychologist specializing in sleep and behavioral medicine, tells Sleepopolis.

You may also need some tests for an accurate diagnosis. You might be asked to wear an actigraphy device (think of it as a specialized activity tracker) that measures your movements during day and night to get a clearer picture of your sleep patterns. Some people may also need a sleep study to check for other sleep disorders like obstructive sleep apnea or narcolepsy, Jones says. (17)

Treatments for Shift Work Sleep Disorder

You may not be able to change your work schedule, but you can help your body get with the program. The goal of shift work disorder treatment is to reset your internal clock to match your work hours, and your healthcare provider may recommend a few ways to help make this happen: (18) (19)

Bright light therapy: Light is your body’s biggest clue about when to be awake or sleepy. “Bright light exposure may be used to shift the internal clock and sleep-related hormones,” Jones explains. This might mean using light boxes and special glasses to nudge your body’s melatonin production to better match your work schedule. (18)
Light avoidance: Dim things down toward the end of your shift, Jones says, and try as best you can to dodge the sun on your way home (that may mean rocking sunglasses at 7 a.m.!).
Strategic naps: Give yourself a boost with a well-timed nap. Jones advises squeezing in a 30–60 minute rest before your shift or catching a quick snooze if you can during an early break.
Melatonin supplements: “Taking melatonin supplements before the sleep window may help improve sleep duration,” Jones notes. A healthcare provider trained in sleep practices can help with the timing of melatonin when treating SWSD.
Consistent schedule: Our bodies love consistency, even when working non-traditional hours. Dimitriu recommends working several night shifts in a row rather than alternating between days and nights.
Smart caffeine use: Caffeine can be your friend before and during your shift, but skip that 3 a.m. cup if you want to sleep at 8 a.m., Jones says.
Prescription medications: Dyonzak notes that wake-promoting medications, like modafinil (Provigil), might be an option as they can help you stay more alert when you need to be. But these medications are not a substitute for good sleep, and should be discussed with your healthcare provider.
Lifestyle adjustments: As a shift worker, you’re likely getting less sleep than most people — typically 1 to 4 hours less than those working traditional hours. (7) To get closer to the recommended 7 to 9 hours, create a peaceful sleep space (think blackout curtains, quiet, cool, and cozy), and get your family on board with your sleep schedule.

Complications of Shift Work Sleep Disorder

Shift work sleep disorder can affect your health in multiple ways. Let’s look at what researchers have discovered so far:

Heart Problems

Working odd hours can take a toll on your heart health. A small study of female night shift workers found that disruptions to the internal clock from shift work can change how certain genes related to the body’s daily rhythm function, which may increase the risk of developing heart disease over time. (20)

Shift workers are also at higher risk for sleep apnea, and when combined with sleep deprivation, their risk of heart problems can be twice as high as those without sleep issues, according to a review of studies. (21) However, some of these findings need more research to be confirmed.

Metabolic Health Issues

Night shift workers are more likely to develop metabolic syndrome, a cluster of health issues that include high blood pressure, high blood sugar, and increased body fat around the waist. (22) (23)

On top of that, there’s a link between working an increased number of night shifts and high blood pressure, although this connection still needs more research. (23) And eating when your body expects to be sleeping doesn’t help, either. Your internal clock can affect how your body processes food, so eating at night when your body is programmed to fast can disrupt your natural metabolic rhythms. (10)

Weight Gain and Obesity

Shift workers often find it harder to maintain a healthy weight, and it’s not necessarily due to late-night snacking. Research shows that eating later in the day is linked to greater body fat, even if you’re not consuming more calories. (10) When shift work forces you to eat at unusual times, your body’s metabolic processes can get confused, potentially making weight management more challenging. (10)

Decreased Immune System Function

With a disrupted sleep-wake cycle, your immune system can also take a hit. According to a small study, night shift workers have higher levels of monocytes (a type of immune cells) compared to day workers. (24) These disruptions may make shift workers more susceptible to colds, the flu, and other infections. (7)

Cancer Risk

The relationship between shift work and cancer isn’t clear, but researchers have noticed some patterns. Long-term night shift workers, especially those who started before age 30 and work three or more nights per week, may have an increased cancer risk, especially for breast and prostate cancer. (25) But other factors in shift workers’ lives might contribute to this increased risk, like higher stress levels and lifestyle habits such as smoking or drinking. Scientists are still working to understand how shift work affects cancer risk.

Safety Concerns

When your body wants to sleep but you have to work, things can get risky; shift workers are almost three times more likely to have workplace accidents. (2) This is especially true with overnight and long work shifts, like the 12-hour ones. (3) The danger isn’t limited to work, either. The drive home after work can be particularly hazardous, especially after a night shift. (2) (26)

Psychological Effects of Working the Night Shift

Beyond the physical exhaustion of working odd hours, there’s a whole other side to shift work sleep disorder: the mental and emotional toll it can take. Research shows that night workers experience a 42 percent higher risk of depression, and shift workers overall show a 33 percent increase in depressive symptoms compared to those working traditional hours. (4)

“Sleep loss adversely affects neurobehavioral function, leading to cognitive impairments such as trouble concentrating and making decisions, irritability, fatigue, and confusion,” explains Olson. (27) Your patience may run low when you don’t get enough sleep, and suddenly, even minor annoyances can feel like major catastrophes.

It can also throw a wrench into your relationships. Olson adds that sleep loss decreases your level of empathetic accuracy, meaning that you may be less able to understand or interpret others’ feelings. As a result, those in relationships who consistently experience poor sleep are more likely to engage in conflict with their partners. (28) (29)

The social impact can be significant, too. Working when others are sleeping (and trying to sleep when they’re awake) can leave you feeling out of the loop and alone. Jones points out that many shift workers may withdraw from family and friends, which can make mood issues even worse. Some might turn to alcohol or other substances to cope with these challenges. (30)

Daily Routine For Nightshift Workers

Every shift worker’s journey to better sleep looks different, and it definitely takes some trial and error to find what works for you. Here’s a sample schedule for a midnight to 8 a.m. shift, complete with expert tips to help you get better rest. You may want to adjust it to fit your specific situation: (7) (31)

Preparing Your Schedule

Consider gradually shifting your schedule a few days before a schedule change, Dimitriu suggests, similar to adjusting for jet lag. This means if you’re switching to night shift, try staying up a little later and sleeping in longer each day before the change.
For rotating shifts, timing matters. Olson recommends following the clock by moving from morning to afternoon to night shifts instead of jumping backward. For example, it might be easier on your body to go from working 9 a.m. shifts to 3 p.m. shifts to 11 p.m. shifts rather than the opposite.
Stick to the same sleep and wake schedule, even on your days off, to help regulate your body clock, Olson advises.

Before Your Shift

6 p.m. – Rise and shine!
6:30 p.m. – Get some natural light exposure (a walk or outdoor exercise can work great) or use a light box to help wake up your body.
7 p.m. – Shower and eat a healthy meal.
8 p.m. – Spend quality time with family and do household tasks (perfect for catching up with the kids before their bedtime).
9 p.m. – Take a 30–60 minute power nap. This pre-shift nap can boost your alertness, Jones says.
10 p.m. – Have a light meal or snack and a cup of coffee, if needed.
11:30 p.m. – Head to work

During Your Shift

12 a.m. – Start work.
2 a.m. – Good time for caffeine if you need it, but this should be your last cup.
3–3:30 a.m. – Quick nap during break if your workplace allows it.
3:30–4 a.m. – Have your “lunch,” but skip the coffee. Olson recommends avoiding caffeine during the later part of your shift so you can fall asleep when you get home.
7 a.m. – Start winding down.

Pro Tip: If you spend a lot of time looking at screens during your shift, blue-light blocking glasses can help reduce eye strain and protect your sleep-wake cycle.

After Your Shift

8:15 a.m. – Commute home. Time to wear those sunglasses to block sunlight exposure that might make it harder to sleep when you get home.
8:45 a.m. – Light snack if you’re hungry.
9:15 a.m. – Wind-down routine: dim lights, avoid screens, maybe some light stretching.
9:45 a.m. – Bedtime! Make sure your room is dark (blackout curtains are your friend), cool, and quiet.
6 p.m. – Start the cycle again.

Pro Tips:

After a long night shift, your bed is calling, but your driving reaction time may not be its best. Having someone pick you up or using a ride-share might just be your smartest and safest move.
Make sure your family and roommates know the ground rules when you’re sleeping during the day.
Put your phone on “Do Not Disturb” mode while you sleep. Those telemarketers and spam calls about your car’s extended warranty can wait until you’re awake. Better yet, keep your phone in another room entirely if you can.

Not everyone’s body clock is built for night shifts. Jones recommends taking an honest look at how well you’re adapting. And if you’re consistently struggling, maybe it’s time to consider work schedules that better match your natural sleep patterns.

The Last Word From Sleepopolis

Adjusting to shift work can be tricky, and finding reliable information about managing your sleep shouldn’t add to the challenge. That’s why our team at Sleepopolis dives into the latest research and works with sleep specialists to bring you practical guidance.

There’s no one-size-fits-all solution when it comes to managing shift work sleep disorder. Take what works for you, leave what doesn’t, and don’t be shy about talking with a healthcare provider if you’re struggling. Good sleep is possible, even when you’re working against the clock.

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