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The demand for brighter, more energy efficient lighting has driven innovations to develop substitutes for incandescent sources. One of these substitutes are light-emitting diodes (LEDs), which are now widely used in commercial and domestic applications, such as computer and mobile devices. There has been some concern over blue light emission from these devices, particularly since we use these regularly for long periods of time at work and during our leisure time. In response to this, blue-light-blocking glasses, which have a coating that filters out blue light, have been marketed as a solution to reduce exposure. This begs the question: Should we be concerned about blue light and are blue-light-blocking glasses a legitimate solution?

What is blue light and is it harmful?

Blue light is part of the electromagnetic spectrum that is visible to the human eye, and it has a shorter wavelength than the majority of all visible light. This is important because the shorter the wavelength of light, the higher its energy. High electromagnetic energy (or radiation) can have adverse effects on human health; this is why exposure to gamma rays, x-rays, and ultraviolet light can be hazardous. Regarding blue light, there have been multiple claims that exposure to it can cause digital eye strain (DES), sleep disruption, retina damage, and macular degeneration. Let’s look at the evidence-based research and see what the experts have to say:

  • There is no evidence that blue light damages your vision; it does not cause retina damage or macular degeneration. If you have ever heard this claim, the results are based on research performed on mice or in-vitro studies; research on blue light exposure on humans has never shown this. To put this further into perspective, we are exposed to blue light up to 100 times more from sunlight than that of artificial lighting.
  • If your eyes have ever felt irritated, itchy, or strained after looking at a screen for an extended period of time, you may have experienced DES. Although blue light may exacerbate DES symptoms, it is not the primary cause for DES. Not to worry; DES is transient and does not cause vision damage. If you want to learn more about DES, we’ve got you covered! Here’s a deeper dive into DES and how to manage it: give-your-eyes-a-break
  • From a limited amount of research, there is support that blue light is involved in circadian rhythm (sleep-wake cycle) regulation, and night-time exposure may lead to poor sleep quality. This may be why using your mobile device prior to going to bed makes it difficult for you to fall asleep.

Should you purchase blue-light-blocking glasses?
If your incentive is to prevent eye damage, there’s no need to invest in blue-light-blocking glasses. Additionally, there’s no strong evidence that blue-light-blocking glasses reduce eye strain and fatigue. That being said, wearing them isn’t harmful; if you find that they help you work, sleep, and feel better, keep rocking them!


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