Strategies for Night Shift Workers

Patient Information Brochure


Challenges involved in night shift working

It is a commonly known fact that many working hours are known to have an impact on one’s sleep-wake cycles, but among others, the most challenging are those that involve a night shift. In view of the fact that we belong to diurnal species (active during the day), our biological clock sends a powerful signal to keep us awakened during the day. Therefore this makes it extremely difficult for night shift workers to sleep well during the day. In fact, this is why night shift workers most commonly complain about lack of sleep and fatigue. On average, a night shift worker sleeps for nearly 1 and a half to two hours less than a daytime worker. This lack of sleep accumulates within the course of several working nights and cannot be entirely recovered during their days off. Consequently, this lack of sleep can eventually get accumulated over the years and may contribute to the development of certain health problems.

The biological clock not only controls our circadian rhythm, but it also includes all other body rhythms, including the rhythms of various hormone levels and those related with the assimilation of food. For example, the melatonin hormone is normally secreted at night which facilitates sleep, whereas the cortisol hormone particularly secreted in the morning, promotes wakening. For the night shift worker, this means that while melatonin will act to increase drowsiness during work, cortisol will inhibit his daytime sleep. In addition, the biological clock schedules our body in such a way that it should receive food during the day and not during the night. Therefore when meal hours are adjusted in order to meet the requirements of the night shift, digestive problems can be often experienced, in the form of either a disturbed appetite or an increased blood cholesterol level.

The long-term issues

Poor sleep and digestive disorders may tend to become more frequent and more severe after about 4 to 5 years of fixed or on rotation night working. Age is also a significant factor: as we get older, it becomes more and more difficult to sleep during the day. This is why employees who’ve worked at night for nearly 20 years without much difficulty are often seen intolerant to work when they reach 40. This being said, it is also important to know that not all experience hardships working at night and these employees can do so without any problem throughout their working life. We believe that these people represent approximately 10% of the workers exposed to night shift work. In most cases, these workers are natural “night owls”, with a spontaneous tendency of going to bed and waking up at late hours. They often require less sleep, which means that they feel rested and alert with as little as 6 hours of sleep a night. They are naturally strong and seldom sick.

Over the past 10 years, several investigations have shown that working at night for a number of continuous years could aggravate certain risks in the long-term, particularly in relation with cardiovascular diseases, metabolic problems such as diabetes and certain cancers. These studies are however inaccurate and the exact duration of the night shift which may increase these risks is yet to be found: certain studies say 15 years, others state that it’s more than 25 years. Similarly, the exact cause for the increase of these risks is as yet unclear, but it’s more likely that lack of sleep and disruptions in the biological clock are involved. Hence, strategies to facilitate the adaptation to night shift working and thus reduce various health problems will principally focus on overcoming lack of sleep and on stabilizing the biological clock.

Strategies to reduce sleep deprivation

Give more priority to sleep!

What you really need above all, is always a good sleep. It is absolutely essential that one must prioritize one’s sleep above all other things and this includes family, friends, shopping, household and even golf! Sleep deprivation can reduce your energy, distort your humor, and contribute to hormonal upheaval. There is also evidence that lack of sleep increases cardiovascular risks and metabolic disorders in the long-term and contributes to weight gain and obesity risks. Therefore you must necessarily try to sleep as much as possible before and after your night shift, and make sure to catch up on lost sleep during your days off.

Control your environment

Even if sleeping during daytime can turn out to be quite difficult due to the wake up signal of your biological clock, you can always control certain factors and significantly improve the quality of your sleep. Opaque curtains for your bedroom windows are essential both for your sleep as well as for your biological clock. You can also get an air conditioner: this will make it easier for you to sleep in a fresh environment and the air conditioner’s white noise helps cover certain undesirable ambient noises. Certain night shift workers successfully use a basement room when they sleep during the daytime: it’s fresher, darker, and is often calmer than their usual rooms. Minimize interruptions during sleep: explain to your family and friends that your sleep is widely important and that it should not be disturbed. Disconnect ringtones and forward your phone calls to your voicemail.

Maintain a regular sleeping schedule

Always try to sleep at the same time when you work at night. This promotes a better sleep and helps your family members and friends not to disturb you at this moment of the day. Maintain the same routine before bedtime, whether you are sleeping during the night or at daytime: for example, brush your teeth, wear your pajamas, read a few pages of your bedside book, etc. Following the same routine always helps your body and mind get ready for sleep. The last thing you’d want to do is doze off on the sofa in front of the television...

Take a nap

Sleep as much as you can. If possible, take a nap during the evening before going to work. You will hence avoid part of the accumulation of lack of sleep and will increase your vigilance at work. Even if you do not sleep, a one-hour nap in a dark and silent room will help you feel more rested and relaxed. In certain working environments, taking a small nap during the night at a meal break is allowed. If this is so, see if it suits you. Some people find that a 20-30 minute nap regenerates them and helps them complete their working night successfully. For others, it’s the opposite: after a nap, they feel rather confused and sleepy (also known as “sleep inertia”). If this is your case, you are more recommended to avoid taking a nap and instead replace it with a peaceful moment of relaxation.

Limit caffeine, alcohol and hard-to-digest foods

Avoid taking caffeine at least 5 hours prior to your bedtime. Not only does this include coffee, but also tea, energy drinks and chocolate as well. Respecting this recommendation could most likely be a rather difficult task, for this means that your last cup of coffee will be removed in the middle of your shift work and that you could feel the need to take a stimulant later, particularly for the trip home. The problem is that caffeine remains in the blood for a long time. Caffeine will generally not prevent you from falling asleep, since you’d already be very tired by the end of the night shift. However, your sleep will be less deep and you will wake up more often. A similar phenomenon is also evident with alcohol: a glass or two can help you relax after work, but your sleep will not gain a good recovery. Take a light but nourishing lunch before going to bed (for example high-fiber cereal accompanied with dried fruits and nuts) and avoid fat and spicy food. You will sleep better and will not be woken by hunger too soon.

Try not to rely on sleeping pills to sleep during the day

Trouble getting to sleep during the day after the shift work is not a transitional problem, but a chronic issue. But regularly using sleeping pills to overcome this problem increases your risks of tolerance and dependence and can inhibit your night time sleep during leave. However, you still need to sleep as much as possible and, having discussed with your doctor; you could decide on using a medication occasionally. Certain night shift workers consider that taking melatonin (3mg) before bedtime helps them sleep better at daytime, but scientific results on this matter are rare and contradictory. Based on current knowledge, there does not appear to be any contraindications or a risk of dependence, hence you could give it a try and see if it helps you.

Strategies to stabilize your biological clock

Adjust the biological clock of night shift workers?

It is very rare when the biological clock gets adjusted to one’s night shift working hours. In fact, even if the worker stays awake throughout the night and sleeps during the day, the rest of the day-night indications, especially the light-dark cycle, will still remain the same, preventing a complete adjustment in the biological clock. During each schedule change, the central biological clock and all other small biological clocks located all around our body try to re-synchronize, but they all do this at various speeds, causing a state of internal desynchronization. Although never formally demonstrated, there is a growing perception that it is this state of internal desynchronization that is most harmful for our health, once it has been repeatedly occurred for many times over the years. Therefore, rather than trying to force a complete adjustment which will be compelled to restart with every schedule change, current recommendations preferably focus on a partial adjustment, capable of providing a certain stability for our body’s biological clock. The best strategy to reach this goal varies depending on when one choses to sleep during his night shifts.

Sleep after the night shift

For most people, going to bed as soon as possible after their night shift will ensure a longer and a deeper sleep. This sleeping schedule has an added benefit of sparing sometime in the afternoon and evening for friends and family. If possible, plan a fixed duration (for example from 9 am till 11 am in the morning) which will always be dedicated to your sleep, both during working days and days off. This regular sleeping period helps stabilize the biological clock and allows you to sleep better after the night shift without causing major disruptions during the days off. To facilitate sleep and the partial adjustment of the biological clock using this strategy, it is important to avoid exposure to morning light, between finishing work and during bedtime. Therefore, you will need to wear sunglasses so as to avoid stimulating your biological clock at this moment of the day. Increasing exposure to light in the evening and during the first half of the working night will be also beneficial. Sleeping in the darkest possible room is also essential.

Sleep before the night shift

Another possibility that can be considered is mainly to sleep before going to work, for example from 3 pm till 10 pm. This option is rarely chosen by young night shift workers, but it could prove appropriate for older people or who are naturally early. This strategy gives you the advantage of reducing fatigue and stress during the night shift and allows you to benefit from the sun, especially in winter. Moving onto a daytime schedule will also be easier. On the other hand, it is important to have a good nap before your first night shift. This is a productive strategy suitable for a night shift worker who has always slept after his night shift but begins to face adaptation issues at the beginning of about forty. To exercise this strategy, being exposed to the morning light is beneficial (a great time for jogging!), but during summer, you must wear a pair of sunglasses in the evening. Once again, sleeping in the darkest possible room is also widely essential.

Adopt a healthy lifestyle

Owing to the fact that night shift working can have several potential negative effects against your health, it is important to minimize all other risk factors in your lifestyle to the greatest possible extent. Night shift working is not merely a risk that can be added with the rest, but it appears to multiply harmful effects, particularly the risks associated with smoking, not exercising and obesity. Regular physical activity and a good balanced diet are particularly important for night shift workers. It is advisable to avoid taking heavy and high-fat food, especially during the night. Since health problems can increase with age and the duration of exposure to night work, it is recommended to get a regular medical follow-up (annually if possible). Informing your doctor about the working schedule can make it easier to identify and prevent potential problems.

In conclusion...

Night shift working is unusual for human kind. Hence, facing hardships is most natural with this working schedule. Nonetheless, there is still a window of opportunity for minimizing adaption issues and other health risks by using strategies that will allow you to sleep better and gain a certain stability in the biological clock and by adopting a healthy lifestyle.


Authored by:
Marie Dumont, PH. D.
Center for advanced research in Sleep medicine
Sacred Heart Hospital of Montreal
Department of psychiatry
University of Montreal