Blue light is not a new phenomenon. As well as coming from our phones, there are also high levels of blue light emitted from televisions, for instance.
The sun is the most significant contributor to blue light. Vibrating within the 380- to 500-nanometer range, blue light has the shortest wavelength and highest energy. Blue light contributes to about a third of the light around us.
Blue light is not a term given just for light emitted from the screen. It’s a natural light that is also there in the daytime, helping our attention and reaction times.
High-energy blue light rays scatter a lot easier and faster than other light rays on water and air molecules. This is what makes the sky blue.
Blue light is used tactically in places where people need to stay awake for long hours. For example, hospitals are lit with fluorescent and LED lighting, which emit blue light.
While the cornea and lens of the human eye can block around 99% of UV light to the retina, virtually all blue light gets through.
However, when the sun goes down and the light turns to darkness, we shouldn’t naturally be seeing it, which is where the problem starts.
Light at night is one of the main reasons people don’t sleep well, increasing the risk of depression, diabetes, and cardiovascular problems. It also affects our health in other ways.
Daylight, which is made up of blue light, keeps our circadian rhythms in balance. These are the physical, mental, and behavioral changes that happen according to light. These processes are also relevant to most plants and animals.
The reason for this is because light affects melatonin, a hormone responsible for sleeping rhythms.
Harvard University did a study that changed subjects’ circadian rhythms. Their blood sugar levels increased, throwing them into a prediabetic state. Also, their levels of leptin, a hormone that leaves people feeling full after a meal, went down.
Harvard found exposure to blue light compared to exposure to green light (literally green light–think of a green lightbulb) for six and a half hours suppressed melatonin twice as much and for twice as long (1.5 vs. 3 hours).
The study suggests that shift workers and night owls should protect themselves from blue light with some kind of goggles or glasses.
There are other ways to protect yourself from this blue light at night, like using dim red lights for night lights. Red light is less likely to shift circadian rhythm and suppress melatonin.
Avoiding looking at screens is best at night. But if this isn’t possible, some programs cut out the blue light on your screen during bedtime hours (which you set personally). One of these programs is Flux.
Too much blue light isn’t good for our brains. It has been described as “visual noise.” It can also cause eye strain, headaches, blurred vision, and neck and shoulder pain.
According to Dr. Howard Murad of Murad Skincare, spending four eight-hour workdays in front of a computer exposes you to the same amount of energy as 20 minutes in the midday sun.
Furthermore, the penetration of blue light through the skin causes reactive oxygen species, which leads to DNA damage and a breakdown of collagen and elastic fibers.
However, studies on blue light’s effect on the skin are lacking. One study suggested that people with darker skin who exposed their skin to a lot of blue light experienced more swelling, redness, and pigment changes than people with lighter skin who were exposed to similar levels of UV rays.
The big question is whether manufacturers of products are responsible for the harm that their products are doing to people. The answer to this is complicated. But one thing is for sure: there will not be heavy regulation on how much blue light phones can emit anytime soon.
For example, when people travel between time zones or need to use their devices when other people are sleeping, they shouldn’t have to look at their device with blue light filtered out.
Blue light is necessary to see images’ colors. It isn’t an ideal solution to have our devices manufactured to limit the amount it emits at night. It’s not practical.
For example, when looking at your device with one of these blue light filters, an image of a blue sky would not be blue. If you’re watching a movie, the coloring is completely off.
On the other hand, it bodes well for big tech companies and pretty much any business that profits off of people consuming content. The blue light on our laptop screen is what keeps people awake and watching more YouTube clips, Netflix, and reading articles. But just because they profit doesn't mean they're doing something sinister.
Since there’s no obvious solution, the responsibility is on the user for now. Like with many products available in the market, there is a potential for them to be dangerous, so it’s up to the consumer to find out how using a product can be hazardous and avoid using it that way.
Blue light is not going to significantly harm anyone’s eyes long term. It cannot be presumed that it is damaging people’s skin significantly either. The evidence for blue light skin damage is weak. Any evidence that exists does not suggest it causing severe damage.
However true, spending long hours on devices is still dangerous. Not only does it mess with your biological clock, but it also has been linked to health and social issues.
These real issues associated with blue light are secondary and are a result of spending a lot of hours on devices. These problems include neck pain, strained relationships, obesity, depression, and anxiety.
Sources: (Harvard Health Publishing) (All About Vision) (Harvard Health Publishing) (Allure) (UC Davis Health) (Raconteur) (The New York Times) (Journal of Investigative Dermatology)
See also: How to use technology mindfully
Everybody has heard variations of the statistics before: millennials check their phones 150 times a day; on average people spend over three hours a day on their phones. But why? Certainly our smartphones are entertaining and useless, however, there is another reason for these stats besides our devices being a source of endless fun and necessary for work: blue light.
Yes, the blue light that our screens emit. It messes with our body clocks. But how? And are there any other implications? To learn what blue light is and the answers to these questions and more, click through this gallery.
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Everybody has heard variations of the statistics before: millennials check their phones 150 times a day; on average people spend over three hours a day on their phones. But why? Certainly our smartphones are entertaining and useless, however, there is another reason for these stats besides our devices being a source of endless fun and necessary for work: blue light.
Yes, the blue light that our screens emit. It messes with our body clocks. But how? And are there any other implications? To learn what blue light is and the answers to these questions and more, click through this gallery.