Blue light, does that mean anything to you? You've most certainly heard of it... And more than once! This is the famous light emitted by your television screens, cell phones, computers, as well as certain toys, connected objects or even your car headlights! While technology or any other elements that emit blue light have an important place in our daily lives, a huge number of studies indicate the undesirable effects of it, both on a psychological and physiological level. But what problems are they really? We're going to show you the different problems that blue light can cause, but also the most sensitive people and how to adopt the right actions.

Blue light and its effects

What is blue light?

Before we get into the effects of blue light, let us tell you a little bit more about it. What we call visible light, ranging from blue to red (the colors of a rainbow) is actually just a tiny part of the whole electromagnetic radiation spectrum. These radiations also include X-rays, ultraviolet, microwaves, radio waves, 4G, 5G… all invisible to our eyes.

The light emitted by the sun is perceived as white, but in reality our eyes receive all spectrums – blue, green, yellow, red… the different radiations of a light source are called its “emission spectrum”. Modern lighting mainly involves “LEDs”, which have replaced other forms of artificial lighting in recent years. Because LEDs can be easily miniaturized, they are used everywhere in screens, but also in homes, street lamps, schools, factories, cars… Standard LEDs (what we call “cool white”) have a simpler emission spectrum than that of the sun, mainly blue and yellow. The combination of these two colors of light is enough to create the impression of seeing white. The natural light emitted by the sun is important for regulating your circadian rhythms. But again, in the evening, high exposure to the blue light emitted by your screens will suppress melatonin (the nighttime hormone) and cause difficulty falling asleep and the quality of your sleep.

No wonder when you turn on a light to feed, comfort your baby or simply go to the bathroom in the middle of the night you have trouble falling back to sleep! Even a simple little night light that emits blue light sends a signal to your brain telling it “it’s daytime”.

The effects of blue light on health

Blue light is taking up more and more space in our daily lives. Blue light in itself is not a problem (as already said it is imperative to expose yourself enough in the morning so that the blue compound stimulates and synchronizes our circadian clocks), it is all in the time of day when we are exposed. It is important to know the risks we face in order to do everything possible to try to reduce them.

Disrupted circadian rhythms

As mentioned earlier, by exposing yourself to blue light at an inappropriate time, you are disrupting your internal clock . If you expose yourself to strong blue light in the evening, you will block your melatonin (nighttime hormone), making it harder for you to fall asleep.

Eye toxicity

Blue light (often present in white light without realizing it) can generate undesirable effects for the eyes:

• Blurred vision
• Irritated eyes
• Headaches
• Age-related macular degeneration (AMD)! Long-term chronic increase can increase the risk of AMD.
• Eyestrain and migraines

Blue light therefore has a strong impact on our body, and some people need to be more careful about their exposure to blue light because they are more sensitive to it.

Who is most sensitive to blue light?

Sensitivity to blue light can vary from one person to another due to several factors: age, pathologies, professions, etc.

Here are the types of people who are most sensitive to blue light:

• Infants, children and adolescents : their crystalline lens (the lens inside the eye that allows light rays to pass through) filters less light because it is more transparent and lets more radiation through.
• People who suffer from eye diseases or abnormalities: Some people no longer have a lens or have an artificial lens (after cataract surgery for example).
• Individuals suffering from migraines : due to variations in light
• Professionals exposed to LED lighting and those who work at night : disruption of the circadian clock

As you will have understood, many people are more sensitive to blue light than others! But whether you are very sensitive or not, it is still important to have good actions when faced with this harmful light.

Adopt the right actions when faced with blue light

To combat blue light, you can change some of your habits if you haven't already!

Recommended practices:

• In the rooms of the house where we will rest (the living room, the bedrooms), use LED lighting with a “low color temperature” (called “warm white” and indicated on the LED packaging as having a color temperature below 3000 Kelvin (K). They emit less blue and their emissions have a more orange appearance.

• On your computers and smartphones, install a “party mode” app that will automatically filter out a lot of blue emissions from a certain time.

• Favor indirect lighting or a lampshade

• Pay attention to the light emitted by the objects and toys you buy (increasingly miniaturized LED bulbs are very powerful and intense, never point them directly into your eyes!). More information on LEDs in toys .

• Avoid screens before going to bed so as not to block the secretion of melatonin (night hormone). ANSES (French National Agency for Food, Environmental and Occupational Health Safety) recommends not being exposed to screens approximately two hours before going to bed.

• Use the Byeblues baby lamp which emits red light and not blue light

Furthermore, if you are pregnant, it is more advisable to limit the use of devices that emit blue light before going to bed and during the night. This would avoid impacting the biological clock of the unborn child.

Conclusion

As you will have understood, blue light is not as harmless as you imagined... Indeed, regular exposure over years can have several long-term consequences on your health. In addition, some people are more sensitive than others due to their age, their eye health, etc. But we must all make sure to reduce our exposure to blue light as much as possible. This can be done through small daily actions or through larger changes in habits depending on your exposure to blue light.