Mastering Your Body Clock: The Key to Better Health and Shift Work Success
Light exposure is more than just about vision; it's a major player in our physical and mental health. How? Timing is everything! Knowing when to get the right kind of light is like having a switchboard for your body—determining when you’re most alert, when your body temperature should peak, and even when it’s time for a bathroom break. Light isn’t just a cue for waking up; it helps regulate body temperature, blood pressure, and the pace of chemical reactions in your body.
In this blog, we’ll delve into the science of your body’s internal clock (also known as the circadian rhythm), how light plays a role, and how to make this natural rhythm work for you—especially if you're a shift worker trying to manage odd hours.
What is the Body Clock, Exactly?
Your body clock is more than just a metaphor. It’s a network of genes and proteins working in rhythm to keep everything in your body ticking smoothly over a 24-hour period. This internal timekeeper—also called the circadian clock—runs on a cycle of about 24 hours and 30 minutes on average. Every day, it syncs up with the world around you through light exposure, especially in the morning, to reset and start fresh.
Here’s a crucial point: the body clock isn’t just one big central timer. It’s a system of clocks in nearly every cell in your body, from the brain to the gut. The central clock, found in the hypothalamus of the brain, syncs up with light signals from cells in your eyes. This central clock then coordinates with clocks in your organs, like the liver, kidneys, and gut. The result? A body that runs in harmony with the daily cycle of light and dark.
Light and the Role it Plays in Health
Why is light so important? Each morning, the central clock in your brain gets a reset from exposure to light, especially blue light. Morning light exposure not only wakes you up, it aligns your body with the environment and helps keep all those cellular clocks in sync. Without morning light, your body clock starts to drift, which can lead to that ‘out of sync’ feeling. For shift workers, getting this dose of morning light can be challenging but finding a way to sneak in daylight exposure (even if it's later in the morning) is essential to help manage your energy levels.
Another factor is when you eat. Food intake also helps reset clocks in your organs—particularly the liver and gut—acting as a secondary cue to align with the day-night cycle.
How Your Body Clock Affects Sleep
Melatonin, a hormone produced in the brain, is the precursor to sleep. Melatonin notifies the body it’s dark outside and it’s time for rest. It’s released as your central clock winds down for the day, preparing you for sleep when it’s time to go to bed. Blue light exposure after sundown, however, tells your body to pause melatonin production, signaling it’s not yet time to sleep. In an ideal world, melatonin rises at night, peaking around bedtime, and drops off in the morning.
Disrupting this rhythm with artificial blue rich light—TVs, phones, or street lamps streaming through windows—can throw off your sleep. Research shows that exposure to blue light at night can lead to mood issues like depression and anxiety, disturb blood sugar metabolism, and even increase long-term health risks. And for the light sensitive “night owls” among us, these effects are often amplified.
The Impact on Shift Workers
For those of us in shift work, our schedules can feel like we’re fighting against this natural cycle. Being exposed to blue rich light at night can mess with your clock, leading to what’s known as circadian misalignment. This mismatch is connected to health issues like increased risk of cancer, heart disease, and diabetes. But understanding the role of light means we can be proactive with our habits. Getting morning day light when possible, using blue-light-blocking glasses at night, and keeping a consistent sleep routine are just some ways to help combat the effects.
The Gut and Circadian Rhythm
Did you know your digestive system has its own clock? For instance, the muscles in your gut that move waste are more active during the day than at night. Around 6:30 a.m., these muscles kick into high gear—this is why you may feel the need to visit the bathroom first thing in the morning.
Like the rest of your body, the gut’s daily rhythm is in tune with the central clock. But, it’s also influenced by food timing. Eating on a regular schedule helps keep this rhythm intact, and for shift workers, it’s essential to eat consistently (if possible) to help the gut keep pace with your schedule.
Focus and Alertness Throughout the Day
The body clock also has a hand in your mental focus. Brain function fluctuates throughout the day, peaking in the late afternoon and evening while dipping in the early morning. This means your mental sharpness and reaction times vary depending on the hour.
Have you ever noticed how concentration dips during a night shift or after a daylight savings change? That’s because your body hasn’t had time to catch up with the shift in light cues. Staying alert during these low-energy periods can be tough, which is why aligning your tasks to your natural alertness windows is ideal.
Other Bodily Functions Governed by the Clock
The body clock controls more than just sleep and digestion. Here are some other areas it affects:
Physical Performance: Muscle activity is higher during certain times of day, impacting how effective exercise is.
Blood Pressure: Hormones regulating blood flow are influenced by your circadian rhythm.
Body Temperature: Fluctuates based on your metabolism and activity levels.
Detoxification: Liver and kidney function in breaking down toxins follows a circadian rhythm, impacting how your body handles medications or alcohol.
The Power of Morning Light
All this science points to one thing: morning light is key. Regular morning light exposure aligns your body clock, setting the tone for a day of better energy, digestion, and even mental health. For those of us in shift work, finding ways to incorporate daylight into our routines can make a big difference. Whether it’s a walk, having breakfast outside, or even positioning yourself near a bright window, the goal is to signal to your body that the day has begun.
Genetics also play a role in how our body clocks operate, which is why some people are natural early birds and others are night owls. But even if you’re wired to prefer late nights, creating consistent light exposure habits can help you feel more aligned.
Let’s look at some tools and strategies that should help you create an environment conducive to quality rest, even during the most challenging shifts.
Practical, evidence-based strategies to optimise your light exposure as a shift worker:
1. Prioritise Morning Light Exposure
Why it works: Getting light exposure in the morning is like hitting a reset button on your circadian clock, which helps keep your body aligned with a 24-hour cycle.
How to do it: Spend at least 20-30 minutes outside within the first hour of waking, ideally in direct sunlight, even if it’s cloudy. Morning light has high blue light content, which is essential for signaling to your body that the day has started.
Shift worker tip: If you’ve just finished a night shift, consider wearing sunglasses on your way home to avoid morning light, which can make it harder to wind down and sleep. Try to get your morning light exposure after a good rest if possible, or later in the day.
2. Use Light Therapy (retimer3 glasses are perfect for this)
Why it works: Light therapy can simulate natural sunlight, particularly helpful for shift workers or during winter months when natural sunlight is limited.
How to do it: Use retimer3 for 20-30 minutes shortly after waking up or before a shift.
Shift worker tip: For night shifts, try using retimer around the start of your shift to enhance alertness. Avoid using it close to your bedtime, as it can delay melatonin production and make it harder to fall asleep.
3. Block Evening Blue Light ( block blue light glasses are perfect for this )
Why it works: Blue light from screens, fluorescent lighting, and LED lights can disrupt melatonin production, making it harder to fall asleep. Reducing blue light exposure after sunset helps prepare your body for sleep.
How to do it: Use blue-light-blocking glasses for at least 2-3 hours before bedtime.
Shift worker tip: If you’re on an overnight shift, try wearing blue-light-blocking glasses in the last couple of hours, especially if you’ll be going to bed soon after finishing work. This can help reduce the alerting effects of artificial light exposure.
4. Create a Dark Sleep Environment
Why it works: Exposure to even small amounts of light while sleeping can impair sleep quality. Darkness signals your brain to maintain melatonin production, ensuring a deep and restful sleep.
How to do it: Invest in blackout curtains, use an eye mask ( I recommend Manta Sleep) , and ensure any small light sources (like LEDs) are covered or removed from your sleep space.
Shift worker tip: For daytime sleep after a night shift, consider using blackout curtains and a white noise machine to block out both light and noise distractions. The Manta eye mask is a portable option if blackout curtains aren’t feasible.
5. Leverage Midday Light Breaks
Why it works: Getting a dose of natural light around midday (which has a high level of blue light) can increase alertness and support a stable circadian rhythm.
How to do it: Try to spend 10-15 minutes outside during your workday, ideally during lunch breaks.
Shift worker tip: For night shift workers, taking a brief break outside can also help reset alertness levels without disrupting your sleep schedule. Fresh air and natural light exposure can make it easier to stay energised throughout the shift.
6. Use Arcashift Shift App (learn more here)
Why it works: Tracking sleep patterns helps you understand when you’re most alert and the best times for sleep, exercise, and meals.
How to do it: Arcashift offer personalised feedback based on your sleep and activity data. The Arcashift app is particularly helpful for shift workers as it provides customised schedules based on your own personal circadian rhythm.
Shift worker tip: This apps will provide you with evidence-based insights on the best times for sleep and naps based on your rotating shift pattern. Aim for consistency where possible, and pay attention to when you feel most rested to build a realistic sleep routine.
Recommendations for blue light blocking products and nap-friendly setups to help you optimise sleep quality and alertness while managing the demands of shift work:
Blue Light Blocking Products
1. Blue-Light-Blocking Glasses
· Why they're effective: These glasses filter out the blue light from screens and artificial lights that can delay melatonin production and make it harder to fall asleep.
· What to look for: Glasses with an amber or orange tint usually block a larger spectrum of blue light.
· Top recommendations:
Swanwick Sleep Swannies – Known for high-quality blue-light-blocking glasses with both daytime and nighttime options.
Block Blue Light – Premium glasses with lenses that block blue and green wavelengths, available in different strengths for daytime and evening use.
2. Zero Blue Lighting
· Why they're effective: Zero blue light globes minimise blue light exposure before bed.
· What to look for: Light Bulbs that are rated with zero blue emission.
· Top recommendations:
Block Blue Light - Zero Blue Lighting– Bulbs, Book readers and sensor lights that emit zero blue light, perfect for winding down in the evening.
Creating a Nap-Friendly Environment
1. Blackout Curtains
· Why they work: These curtains block out sunlight and external lighting, creating a dark environment that signals your body it’s time to rest, which is especially helpful for daytime naps after a night shift.
· What to look for: Curtains with thick, multi-layered fabric that effectively blocks light and reduces noise.
2. Sleep Masks
o Why they work: An eye mask is a simple, portable solution that provides complete darkness for sleep, helping you fall asleep faster and stay asleep.
o What to look for: Masks with adjustable straps and contoured designs that relieve pressure on the eyes.
o Top recommendations:
§ Manta Sleep Mask – Customisable and contoured for a blackout effect without pressing on the eyes. The best of the best.
3. White Noise Machines
· Why they work: White noise machines mask disruptive sounds, like street noise or household activities, that can disturb your nap.
· What to look for: Choose models with volume control, adjustable sound profiles, and automatic timers.
4. Essential Oils and Diffusers
· Why they work: Scents like lavender and chamomile have been shown to promote relaxation, making it easier to unwind and fall asleep.
· What to look for: A diffuser with a timer function, so you can let it run briefly before napping and turn off automatically.
Tips for Napping Like a Pro
Nap Duration: Aim for a 20-30 minute power nap if you’re looking to refresh without feeling groggy. For a deeper rest, a 90-minute nap allows you to complete a full sleep cycle.
Pre-Nap Routine: Establish a relaxing pre-nap routine to wind down. This could include turning off bright lights, setting up your white noise machine, and using calming essential oils.
Consistency: Try to nap around the same time each day when possible. This helps train your body to expect rest at that time, even if it’s unconventional compared to typical schedules.
To integrate these blue light blocking and nap-friendly tools into your daily routine, here’s a structured approach that will help align your body’s rhythms, improve energy, and support restfulness around your shift work demands:
Before a Night Shift
1. Maximise Natural Daylight Exposure:
Get outside in the morning or early afternoon to anchor your circadian rhythm with natural light exposure. Even 15-20 minutes of daylight can boost alertness and mood.
Use retimer3 if you’re unable to get outside, especially on shorter winter days.
2. Use Blue-Light-Blocking Products in the Afternoon:
If you need to rest before a night shift, start wearing blue-light-blocking glasses about 1-2 hours before winding down.
Switch to zero blue light lighting in your rest area. This prepares your body for rest, despite the unconventional sleep timing.
3. Nap Preparation:
Use a 30-minute pre-nap routine to signal your brain that it’s time to wind down. Set up your blackout curtains and dim any ambient lighting to create a calming atmosphere.
Try a short, power nap (20-30 minutes) or, if time allows, aim for a full sleep cycle (90 minutes) to avoid grogginess.
Incorporate a white noise machine if household noises are common, and use the Manta eye mask for added darkness if needed.
During Your Night Shift
1. Avoid Eating Large Meals During DLMO (Dim Light Melatonin Onset):
If your body is exposed to light during the night shift, keep your meals small to avoid metabolic strain. Reserve larger meals for times when you’re off shift and can eat during daylight hours.
2. Use Light Strategically to Stay Alert:
Consider using blue-light emitting devices (like specific bulbs or retimer 3 in the first half of your shift to stimulate alertness.
Around 4-6 hours before your shift ends, switch back to zero blue light or wear blue-light-blocking glasses again to help your body start winding down towards sleep when you finish work.
3. Nap Breaks:
If your schedule allows, take a short power nap of 20-30 minutes on breaks. This will prevent deeper sleep that could lead to grogginess. Use a Manta sleep mask and noise-canceling headphones if your nap area isn’t completely dark or quiet.
Use a white noise machine to minimise distracting noises, especially in break rooms with ambient sounds or people.
Post-Shift Wind-Down
1. Simulate Night Time to Encourage Sleep:
On your way home, wear blue-light-blocking glasses, particularly if it’s morning. Exposure to sunlight may hinder melatonin production, making it harder to fall asleep.
Once home, create a dark, cool environment for sleep with blackout curtains, a white noise machine, and your eye mask.
2. Temperature Control:
Set up your room temperature between 15-20°C (60-68°F) for optimal sleep. If that’s challenging, try using a cooling pillow or an electric fan.
3. Use Calming Scents and Routine:
Set up a lavender essential oil diffuser or apply a calming sleep spray to your pillow. The scent will signal your body that it’s time for rest.
Avoid any screens or bright lights for 30-60 minutes before sleep to allow melatonin levels to rise.
During Day Shifts or Off Days
1. Maintain Consistent Habits:
Try to keep similar wake-up and sleep times, even on off days, to reduce circadian disruption. This consistency minimises jetlag-like symptoms between your shifts.
Expose yourself to as much natural light as possible during the day, which reinforces your circadian rhythm, keeping it more resilient to night shifts.
2. Practice ‘Light Diet’ on Your Days Off:
Keep bright light exposure in the early part of the day and dim lights in the evening. This helps create a solid day-night rhythm.
Utilise your ero blue lighting to slowly dim in the evening to mimic sunset, helping your body wind down naturally.
3. Use Short Afternoon Naps Strategically:
If you’re adjusting back from night shifts, a short nap in the early afternoon can boost your energy without impacting nighttime sleep.
For ongoing shift work, naps should be treated as “strategic tools,” so keep them brief and refreshing.
Helpful Reminders for Staying on Track
Consistency: It’s all about habit. Maintaining a structured routine with these tools and strategies will help condition your body to adapt more smoothly to irregular sleep patterns.
Adjust Products to Your Needs: Not every shift will be the same. Use your blue-light-blocking glasses, noise machines, and light sources in combination and adapt based on what your body responds to best.
Small Adjustments Yield Big Results: Even small changes, like adjusting your lighting and taking power naps, can make a big difference in how well you sleep and how alert you feel on shift.
By implementing these products and practices consistently, you’ll create an environment that supports your body’s needs for rest and alertness, empowering you to thrive through shift work with energy and resilience.
Let me know if you’d like guidance on troubleshooting specific sleep issues or incorporating more detailed strategies into your daily routine! I can help you.
Conclusion
Light exposure is one of the most powerful tools we have to regulate our body clocks. For shift workers, this knowledge can be transformative. Small changes, like boosting morning light exposure, managing evening light exposure, and eating on a consistent schedule, can help align your body with your environment.
If there’s one takeaway, it’s this: take control of your environment to keep your body clock in sync. Give yourself the gift of regular light exposure, a consistent sleep schedule, and balanced meal timing, and let your body’s natural rhythms work for you. By doing so, you’re setting yourself up not only for better shift work but a healthier life outside of work, too.
About Roger Sutherland
As a coach and advocate for shift workers, my goal is to provide practical, evidence-based strategies that empower individuals to thrive in their roles. By understanding and addressing the challenges of shift work sleep disorder, shift workers can achieve better health outcomes and lead more fulfilling lives both on and off the job.
Note:
I also run Nutrition, Health & Wellbeing Seminars for shift working environments.
