In nature, there’s not a lot you can consume that’s blue. There’s blue skies, blue seas, and bluebirds; I suppose you could eat the latter, but it sure isn’t common. Blueberries are delicious, but they’re not really blue, are they? More of a purple. While we can’t eat a lot of blue, we do see a lot of it; especially, in our modern age, in the form of blue light. This particular type of light falls between the range of 400−495 nm in wavelength, and much of it is considered high-energy visible light. While some might say “high energy, high pizza”, others are concerned about the long-term effects exposure to blue light can have on your vision.
The primary source of blue light in our electronic age is LEDs. This light comes off to most as whitish in colour, but in fact, falls mostly into this high energy range. The main concern is that almost all blue light passes directly through the eye to the retina; our eyes block UV rays quite effectively, but blue light is in the visible range, despite its intensity. This has created a peculiar problem; long-term exposure to blue light may have a cumulative, degenerative effect on the eyes, especially those of children, which are particularly susceptible to high energy waves.
The cumulative effect of blue light is seen primarily in the development of three issues: cataracts, age-related macular degeneration (AMD) and eye strain. Cataracts are spurred by changes to the eye’s lens; as we age, constant exposure to UV light begins to yellow the lens, which makes it more effective at absorbing blue light before it reaches the retina. This absorption is a contributing factor to cataracts, so the increase in blue light to be absorbed could increase risk. AMD can be caused and aggravated by damage to light-sensitive cells in the retina; these cells can potentially be harmed by cumulative exposure to blue light. It’s important to note that studies about blue light exposure are ongoing; the rise of LEDs is a relatively recent phenomenon, so while more research is needed, caution is always advisable.
The most common problem with blue light is one you’ve likely noticed: sleeplessness. A Harvard study found that blue light suppresses melatonin significantly more than green light; melatonin helps regulate your sleep cycle, so if you’ve been up late staring at your phone, the phone itself may be the culprit. There are tools you can use to block blue light, which can ameliorate the quality of your sleep; during the day, blue light is useful because it promotes wakefulness and a good mood, but consider unplugging a few hours before bed to make sure you get all the benefits of a good night’s sleep.
There is blue light blocking Winnipeg eyeglasses citizens who need corrective lenses can get their hands on. Get in touch with your optometrist if you feel like blue light has impacted your vision or your sleep cycle, and start your path towards a healthier life!