The Effect of Light on The Circadian Rhythm
It’s common knowledge that humans have evolved to be awake during the day and sleep during the night. But to what extent does light affect our sleep, and how can we improve our sleep quality?
Before we dive into the solution, let’s briefly discuss the science behind sleep and why this is so important.
The Circadian Rhythm
According to the Sleep Foundation, this is a 24-hour internal clock that coordinates a wide range of processes in the body, including sleep. This rhythm is controlled by a small part of the brain, known as the circadian pacemaker, that is powerfully influenced by light exposure.
Circadian rhythms can influence important functions in our bodies, such as:
- Hormone release
- Eating habits and digestion
- Body temperature
However, most people notice the effect of circadian rhythms on their sleep patterns.
How does light affect sleep?
Light is the biggest external factor affecting sleep. Light plays an essential role in regulating the circadian rhythm and affects the production of melatonin.
When light enters the eye, it is sensed by a special group of cells on the retina, which is carried to the brain and interpreted as information about the time of day. The brain then sends signals throughout the body to control organs and other systems in accordance with that time of day.
The way light alters circadian rhythm depends on the timing of light exposure. When light is perceived early in the morning, it pushes the sleep schedule earlier. Light exposure in the evening pushes the sleep cycle backwards toward a later bedtime.
Humans have evolved with sleep following regular patterns of sunlight and darkness, however, modern living and our dependence on electricity make illumination possible 24/7. From streetlights to car headlights to phones and computers, artificial lighting is a constant part of modern lifestyles and the night sky.
Daily light exposure, including the type of light we see as well as when and how long we’re exposed to it, has a critical effect on sleep.
Why is good sleep quality important?
We all know that a good night’s sleep leaves us feeling refreshed and alert in the mornings. But the impact of a lack of sleep, or low-quality sleep, actually has a much bigger impact on us than just our energy levels.
Regular disruption to your sleep, like insomnia, can stop your brain from functioning as it should. During a good night’s sleep, your brain prepares itself for the following day, forming new neuronal pathways to help you learn and remember important information.
Getting the right amount of sleep, around 7-9 hours a night for adults, is also crucial for:
- Improving your attention and concentration levels
- Processing information received throughout the day
- Maintaining healthy weight
- Keeping your heart healthy by reducing blood pressure, the risk of heart disease and the likelihood of strokes
- Keeping your immune system strong
- Reducing stress levels
- Looking after your mental and emotional wellbeing
For more on how sleep affects the above, check out this article by BUPA.
Being able to get enough sleep is vital, even if you need to sleep during the day. Shift workers, long-haul travellers or holiday makers might all need to sleep when it’s still light outside.
Good quality sleep is also important for hotels. Research shows that guests who have a poorer quality of sleep are more likely to leave a negative review of their stay than a guest who had a good quality sleep. When sleep quality is affected, guests wake up in a worse mood, so things that they may have dismissed if they had slept better and woke up in a better mood are more likely to stick in their minds and they’ll bring it up in their review.
Our eyes sense light even when they are closed so ensuring hotel bedrooms have total blackout is key to ensuring guests have good quality sleep.
How can we reduce light pollution to improve sleep?
Installing blackout blinds and curtains is a great line of defence against daylight and light pollution entering the room.
Bedroom curtains are about more than just matching the bed sheets – closed curtains offer extra warmth, enable privacy, and have a strong effect on the quality of your sleep. As mentioned before, even the slightest amount of light can jolt you awake and disrupt a good night’s rest.
Curtains form the first line of defence to prevent light from entering your room – meaning you can keep the room in perfect darkness, even in the brighter, summer months.
Our Flow motorised curtain tracks, allow curtains to open and close automatically, giving the occupant the opportunity to allow light into the room at their own pace, not to mention get those extra special few minutes in bed.
For an extra layer of protection, zipped-edge blackout blinds like our KuroLok system are a great solution for blocking unwanted light from bedrooms. Side channels with a zip-insert reduce light gaps down the side of the fabric more than a traditional channel does.
Most traditional channels will have brush edges which does help to block light gaps, but these aren’t quite as effective as a zip-insert. The insert essentially fills the gaps left in the side channels around the fabric, so there’s nowhere for the light to come through.
Some side channels even combine brush and zip-insert for the ultimate blackout, like our KuroLok 56mm channel.
The material used in blackout blinds is specially designed to cut out light and prevent the morning sunrise from disrupting sleep. Blackout blinds also offer noise reducing qualities that can help to shield those unwanted noise disturbances all throughout the night.
For more information on our blackout systems, click here:
For more information on electric curtain tracks, click here:
Sources:
https://www.sleepfoundation.org/circadian-rhythm
https://www.bupa.co.uk/newsroom/ourviews/benefits-good-night-sleep