Sleep & Shift work

sleep Feb 11, 2021


Our sleep cycle is regulated by our circadian rhythm. The circadian rhythm is based on the light-and-dark cycle of the sun and controlled by a part of the brain called the suprachiasmatic nucleus, this master “body clock” gets its cues from several environmental and personal factors, ranging from the amount of light exposure (most significant), to exercise, and temperature.

Our core body temperature(1) hovers around 37 degrees Celsius but fluctuates by about a degree throughout the night. The drop in temperature starts about two hours before you go to sleep, coinciding with the release of the sleep hormone melatonin. During sleep, body temperature continues to fall, reaching a low point in the early morning and then gradually warming up as the morning progresses.

This is all good if you always sleep at night in a regular sleep pattern. Unfortunately for shift workers, this is not the case & therefore those who work night, early morning, or rotating shifts may experience circadian rhythm sleep disorder(2) aka “shift work disorder” (characterized by symptoms of insomnia and/or excessive daytime sleepiness in conjunction with a work schedule that conflicts with traditional sleeping times).

If you are a shift worker experiencing insomnia symptoms and/or excessive daytime sleepiness, there are measures you can take to mitigate the effects of shift work disorder. At the same time, there are certain activities and behaviours to avoid to stay well-rested and mentally prepared for shift work.



  • Maintain a Relaxing Bedroom Environment


The bedroom should serve as a sleep sanctuary no matter what time you go to bed. This is particularly crucial for people who need to sleep during the day. The ideal sleep environment should be dark, relatively cool, and quiet. 

Attempting to sleep during the day can be difficult due to factors like daylight and outside noise. In addition to dimming the lights, you can block outside light using an eye mask or blackout curtains. If your home is located in an area that is relatively loud during the daytime, try earplugs or playing white noise to muffle disruptive sounds.

The best bedroom temperature for sleep is 18 degrees(4), but 16-19 degrees is considered an ideal temperature range. Our bodies are programmed to experience a slight dip in core temperature in the evening which signals your body that it’s time for bed. A cool room can assist in mimicking this dip if day time sleep is required.

The following suggestions can help optimize your bedroom temperature for sleeping:

  • Close the blinds to reduce heat build-up during the day
  • If possible sleeping downstairs on warmer days
  • Use a fan or air conditioning in hot climates, or a hot water bottle when it’s cold
  • Open the windows to promote ventilation
  • Control bedroom humidity
  • Reduce sweating with a breathable mattress, sheets, duvet, comforter, pillow, and lose pyjamas
  • Taking a warm bath(3) an hour or two before going to bed can encourage a natural cool-down effect



  • Practice Healthy Sleep Hygiene


Sleep hygiene refers to daily routines and activities that affect your sleep quality and duration. Healthy sleep hygiene involves not only a restful bedroom environment but also relaxing pre-bedtime routines such as a hot shower or meditating. You should avoid alcohol, caffeine, and heavy meals in the hours leading up to sleep.

Another crucial aspect of healthy sleep hygiene is going to bed and waking up at the same times each day, even on your days off. This can be particularly tricky for night shift workers because they will potentially miss out on social activities and time to run errands.

If you normally work a night shift, schedule your sleep time to wake up close to the beginning of your next shift, rather than going to sleep immediately upon returning home. Studies have shown the “split nap” schedule is also effective. This involves sleeping for a few hours when you get home from work, then staying awake and taking a long nap that ends close to the start of your next shift.


  • Monitor Your Alertness at the Workplace


Those who are new to shift work or assigned a non-traditional shift with extended hours are at higher risk of committing errors or being involved in an accident on the job.

Caffeine can be helpful for keeping you awake during shift work, but moderation is important. Small amounts of caffeine every hour or two can be more beneficial than larger, more sporadic amounts of caffeine which may lead to a “caffeine crash.” Moderate exercise, such as a stroll outside or a visit to your office gym, can also temporarily boost your alertness and energy levels.

Napping at work may also be effective. A short nap of 15-20 minutes (longer than 20 mins can leave you feeling groggy) during one of your scheduled breaks can make you feel more refreshed and alert. Some shift workers find relief from the “caffeine nap,” which involves consuming caffeine immediately before your breaktime snooze. Caffeine needs about 15-20 minutes to take effect, so ideally you will wake up feeling exceptionally alert.

If you feel tired at the end of your shift, consider a brief nap in your car or a designated “nap room” at your workplace.


  • Seek Help if Needed


People with shift work disorder often experience fewer symptoms if they transition to a more traditional work schedule. However, this is not always the case. Speak to a physician if you think your work schedule is interfering with your sleep, especially if symptoms persist for two weeks or longer.

Your doctor may prescribe prescription sleep aids or over-the-counter sleep medications to help you get enough rest. Be sure to discuss side effects, drug interactions, and other important aspects of these sleep aids, and never take any medication without a physician’s approval.

Shift workers are also at higher risk of medical conditions such as cancer and cardiovascular disease(5), as well as depression. Several hormonal imbalances affecting cortisol and testosterone are also common in shift workers, which can result in adrenal insufficiency and hypogonadism respectively. Routine medical checkups can ensure you remain healthy, even if you don’t experience symptoms of shift work disorder.


Written by :

Josh Bolin