As you know, blue light and sleep are some of our favorite topics. And today, instead of just talking to you about the harmful consequences of LEDs and screens on your nights, we also wanted to address the subject of the usefulness of blue light for sleeping well.
⚠️ Spoiler: no, we are not going to give you excuses to spend your nights on the Resident Evil 4 remake under the pretext that it's good for your sleep, and even less so if you do it without anti-blue light glasses!
In this article:
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👨🏫 Blue light: a few reminders
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💤 The benefits of blue light on your sleep?
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➡️ The other advantages of blue light
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🚨 The dangers of artificial blue light
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🛏 Our tips for better sleep
Blue light: a few reminders
💡 Pssst! To be an expert on the subject, we advise you to consult our complete dossier but here is a quick recap.
Light is a wave: therefore, the spectrum of light visible to the human eye is broken down into several colors 🌈
🔵 Blue light corresponds to the portion of the light spectrum with a wavelength between 380 and 500 nanometers. It is therefore the type of visible light that produces the greatest amount of energy.
The two sources of blue light are natural light (daylight) and the artificial light from screens and, in particular, LED lighting.
Blue light is itself broken down into 2 categories:
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Turquoise blue light (between 450 and 500 nanometers), which is essential for regulating our biological rhythm,
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"Harmful" and "ultra-harmful" blue light (between 380 and 450 nanometers), closer to UV, which carries risks for the health of your eyes and the quality of our sleep.
👉 This distinction is important regarding the impact of blue light on your sleep!
The benefits of blue light on your sleep
Because no, blue light isn't just bad! Everything depends on the frequency, the duration of exposure, and the time of day you are exposed to it.
⏳ Blue light regulates the production of melatonin, the sleep and falling-asleep hormone: it is therefore essential for our circadian rhythm (the day/night rhythm).
Indeed, melatonin is known to promote falling asleep. Its secretion is directly influenced by blue light, which blocks it in the morning to encourage our natural awakening with the sunrise ☀️
Conversely, when daylight fades, the amount of blue light decreases and melatonin production increases: our body understands that it is time to switch to night mode 🌙
You now understand why blue light is essential to our functioning (but also why exposure to screens can impact your sleep at the end of the day; patience, we'll tell you about that just after).
The other advantages of blue light
Be aware that it also has an impact on your mood: it is said to stimulate responsiveness, helps you stay focused, and helps fight against depression. Daylight increases both the level of serotonin, the happiness hormone, and cortisol, a hormone which, in reasonable quantities, keeps us alert and dynamic.
🍹 It is therefore a "good mood" cocktail served to us every morning!
A British study even highlighted the link between daily exposure to daylight and improved mood. We better understand the famous "seasonal affective disorder," aka the depression we can feel in winter directly linked to the lack of light.
Finally, we sometimes even use blue light (artificial, this time) in the context of dermatological care: acne treatment with blue light is increasingly practiced in clinics or at home.
The dangers of artificial blue light
We mentioned it above, blue light has a direct influence on melatonin production and therefore sleep.
While natural light normally regulates our circadian rhythm and sets our sleep cycles to the day/night alternation, exposure to artificial blue light can disrupt this well-oiled mechanism and have harmful consequences on our sleep.
The problem is that it is omnipresent in our modern societies: urban lighting, light bulbs and LEDs in our homes, and screens used non-stop right up to the bedroom!
Unless you live in a cave, our human body is no longer truly set to a natural rhythm influenced by sunlight, but is instead disrupted by the excessive use of screens in particular: this is how insomnia, difficulty falling asleep, and disruption of sleep cycles occur.
This phenomenon is reinforced by the lack of exposure to natural light.
But that's not all! Overexposure to screens and artificial lighting can also cause harmful effects on your health (studies still ongoing):
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long term: decrease in visual acuity, irreversible vision damage, worsening of AMD (age-related macular degeneration)
short term: eye strain, headaches, blurred vision, back and neck pain, eye irritation, tingling, tearing
Some studies are starting to make the link between overexposure to blue light and cognitive disorders (notably ADHD) but also hormonal ones (acceleration of puberty).
One more reason to protect our children from screens!
Our tips for better sleep
So yes, all this might seem worrying, but don't panic: limiting the impact of screens and lighting on our sleep and our health is possible!
Here are some tips for better sleep:
🥗 Improve your lifestyle: we don't necessarily think about it, but your physical activity, diet, and hydration have an influence on your sleep. You can imagine that a late and/or difficult-to-digest meal is not ideal if you want to sleep like a baby. Similarly, remember to drink water (avoid alcohol or coffee) regularly throughout the day, and not all at once before bedtime.
🧘♀️ Fight against stress which can be a factor in insomnia. A tool that has proven itself at Horus X is meditation, which helps reduce anxiety and makes falling asleep easier and more peaceful.
🖥 Reduce your screen time: it goes without saying! Stop exposing yourself to screens at least 1 hour 30 minutes before going to bed (and protect yourself effectively from their effects thanks to quality anti-blue light glasses.)
🔦 Think about lighting too: as we said, LED light is also harmful to sleep. If you can, choose lighting in red or orange tones for your bedroom and sleep in complete darkness.
Last tip: get out of your cave (yes, it's a running gag)! You now know that daylight is particularly beneficial for setting you to a more natural sleep rhythm, so put down the controller and go for a walk 🚶
In summary: is blue light for sleeping better possible?
Well... yes and no.
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Conversely, overexposure to screens, especially at the end of the day, disrupts our sleep. Our instructions: turn off screens 1 hour 30 minutes before bedtime and no mobile phones on your nightstand!
Natural blue light is essential to help our body differentiate between day and night. It is also used in light therapy, whether to fight depression or skin problems.
