How to work night shifts and stay healthy

Typically, “night workers” in the UK are those who regularly work at least three hours during the ‘night period’, which is generally 11pm to 6am.

In this article, we’ll explore practical things night shift workers can do to minimise the disruption to their health caused by working during the night.

The side-effects of working night shifts

One of the major side-effects of working night shifts is that it disrupts our circadian rhythms.

Circadian rhythm misalignment happens when our body clocks are out of sync with the earth’s natural rhythms, such as the light / dark cycle. When circadian rhythms are disrupted, it has knock on effects that play havoc with key physiological processes like core body temperature, release of the sleep hormone melatonin and stress hormone cortisol, which will lead to further disruption overtime.

A research review linked night shift work with an increased risk of sleep loss, occupational accidents, obesity, weight gain, type 2 diabetes, coronary heart disease, breast, prostate and colorectal cancers. Additionally, as one small study of night nurses indicated, our ability to learn and retain information and cognition, vigilance and sleep-wake patterns may also be impacted.

Of course, our society is dependent on night workers, but the above highlights the need for night workers to explore what they can do to support their health and wellbeing within their individual circumstances.

Even though most permanent or long-term night shift workers’ bodies aren’t able to adapt their circadian system to their imposed work schedule, there are actions they can take to minimise the fallout. We’re all different, so why not experiment with new routines and habits and see what works for you?

Tips for working night shifts and staying healthy

Sport your sunglasses if walking home

The vitamin A-based photopigment melanopsin in the retina of your eyes is activated by the blue light component of daylight. Melanopsin signals to your master clock that it’s daytime, and therefore time to be awake, not asleep. So, blue or bright light exposure just before your daytime slumber will make it harder to sleep, which is why wearing sunglasses even on cloudy days when walking home, may help. Using lamps with red or orange bulbs before going to bed to mimic the colours of sunset may also support your sleep.

However, if you’re switching from night to day shifts, then it’s a good idea to ditch the sunglasses when walking home from your last night shift, to get light exposure to keep you awake until it’s time to go to bed in the evening. Likewise, leave the sunglasses if you’re walking to work during a stint of night shifts, as the light exposure will help keep you alert as your begin your night shift.

Where possible, work in bright light

A more brightly lit night-shift will increase alertness and performance, as well as promote adaptation to night work, although studies vary in detail. This can be tricky especially if you’re a hospital night shift worker because patients need darkness to sleep, but you need bright light. If you can’t be exposed to bright light throughout your entire night shift, there could be benefits to short 15 minute bursts of exposure during the night.

Get seven-nine hours of sleep every 24 hours – even if it’s broken sleep

A phase shift in your circadian rhythms means that your sleep-time and wake-up time will move earlier in the day (phase advance) or later in the day (phase delay). When exposed to light late at night or very early in the morning your circadian rhythm will advance. However, when you’re in light during the evening, it’ll delay your circadian rhythm. Long-term exposure to light in the evening while working nights therefore, prompts you to sleep later in the day and wake up later, resulting in ‘social jetlag’. The term refers to when our work/life schedule doesn’t fit with what’s ideal for our body’s internal biological rhythms.

When is it best to sleep during the day?

It’s widely accepted that getting a good amount of sleep – somewhere between seven-nine hours – within a 24-hour cycle is crucial. However, given your exposure to light, daytime sleeping can be hard, but tips like using blackout blinds or an eye mask can help.

For a longer sleep, better performance and focus on your night shift, you may wish to experiment with spending eight hours in bed and rising one-two hours before you start work, as one small study found doing so had positive results.

Struggling to kip during the day? Trial napping in the afternoon before your shift

Some investigations have found napping before a night shift can dramatically enhance performance and alertness. A one-hour nap prior to your first night shift may be sufficient, preferably between 2pm and 4pm. If that’s not possible, the extra sleep you get is seemingly more important than the time you take a nap.

If having caffeine, have it early in the shift then steer clear

Some researchers have seen that a specific combination of evening napping before a shift and having caffeine at night improved performance and decreased subjective sleepiness in night shift workers. Avoiding it towards the end of the shift will ensure it doesn’t impact your daytime sleep. However, if you’re sensitive to caffeine, which the Evergreen Life DNA Test can identify, this approach may not be for you.

Plan, prep and bring your own healthy food to work

When we’re sleep deprived, we can experience a decrease in our levels of the appetite regulating hormone leptin and an increase in our levels of the hunger hormone ghrelin. The leptin dip and ghrelin boost is likely to result in cravings for calorie dense-foods high in carbohydrates that lack nutritional value. For example, sweets, cakes and biscuits.

Being aware of what you’re eating, for instance avoiding sugary snacks and simple carbohydrates, can help you balance your blood sugar better, which may result in better quality sleep.

As most of the food consumed by shift workers tends to come from canteens, our ‘What is in a healthy diet?’ article can help you nourish your body with your own food.

Try eating your main meal before your shift and having a lighter “breakfast” before your daytime sleep

Eating a light “breakfast” after your night shift, one-two hours before going to sleep in the morning may prevent waking up during the day because you’re hungry. Additionally, it may be unnecessary for shift workers to eat full portions at night during their shift, as satisfaction may occur with less food. In fact, the British Medical Journal advises enjoying your main meal before your night shift can provide your body with much needed fuel to see you through your working hours, as long as you keep it nutritious.

Stick to an eating routine

Whatever eating pattern works for you, regular mealtimes play a role in synchronising your secondary cellular body clocks, particularly when it comes to regulating your blood sugar.

Take a re-useable water bottle and keep refilling it

It can be easy to forget to drink water when busy. However, even mild levels of dehydration can lead to disruptions in mood and cognitive functioning. Staying hydrated may also help you avoid snacking.

Enjoy a cold shower, bath or wild swim when you wake in the early evening

Along with light, temperature is thought to be one of the environmental cues that can regulate your body’s circadian rhythm, which, as we’ve highlighted, can be disrupted when working night shifts. Studies indicate that you may be able to kick start your circadian rhythm and boost energy and heat production by exposing yourself to cold temperatures – priming you for your night shift ahead.

Exercise in the early evening

For night shift workers who need to delay their circadian rhythms, exercising between 7-10pm, rather than between 1-4pm may help avoid an unwanted circadian rhythm advance (i.e. having earlier sleep and wake-up times). Whatever time you decide to get active, it’s wise to avoid exercising 90 minutes before going to sleep. Doing so allows your body temperature, which rises during exercise, to return to one that’s more favourable to falling asleep.

Could you leave the car at home?

With reduced cognitive performance and alertness already consequences of night-shift induced circadian disruption, on top of workers tired from their shift, it’s no wonder 57% of 3,772 trainee anaesthetists surveyed sadly said they’d experienced an accident or near-miss when travelling home from night shifts.

Understand stress

We all experience stress and, to a certain degree, it’s helpful. However, when we get caught up in a prolonged state of “stress”, whether it’s from perceived stress (our thinking about external circumstances) or stress on our body (e.g. poor diet, working when biologically programmed to sleep), it’s important that we do what we can to mitigate the impact.

1. The first step is becoming aware of when we’re experiencing prolonged stress as it can quickly feel like the norm.
   
   
2. The next is to understand where that stress is coming from and make small adjustments, such as the ones above on nutrition and sleep, to minimise the impact.
   
   
3. And don’t forget, you won’t be the only one feeling it, no doubt your colleagues will too; it can be helpful to lean on each other for support.

Working patterns vary and our bodies are all unique, responding differently to different behaviours. We hope this article has sparked inspiration to investigate different areas that may work for you in helping to minimise the circadian disruption and health risks associated with working night shifts. Who knows, maybe what’s successful for you will also support your colleagues and give you ideas to present to your employer?

Tips for employers of night shift workers:

The above are all things that you can action but there maybe some things your employer can do to better support you. For example:

• A potential solution to the tendency for night shift workers to experience sleep deprivation and drowsiness might be to decrease the duration of night-shifts.
  
  
• Support your team’s hydration by investing in water fountains, water filters or welcoming chances for workers to re-fill bottles, perhaps even supplying company branded bottles.
  
  
• Given the impact of night shift work on cognitive function, it maybe helpful for your employer to check in on review protocols within your organisation, for example, cross checks when undertaking potentially dangerous decisions.

Reviewed by:

Nicky Verity Wellbeing Researcher

Anna Keeble MA BA Wellbeing Expert

Dr Claire Marie Thomas MRCGP DFSRH DTMH DipNLP MBChB BMedSci Medical Expert

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