Many people are worried about the effects of blue light. Most digital screens (especially LED screens) emit blue light. Due to the increase in screen time and device usage, more patients are having increased exposure to blue light. Blue blocking lenses reduce short-wavelength light, and blue light has a much shorter wavelength when compared to red or yellow light. People purchases these glasses to alleviate eyestrain from digital devices and to improve sleep quality.
Blue Light And Retina Damage?
There may be some retinal protection offered as well because an association with age-related macular degeneration was previously suggested. There is no strong evidence however to truly support this retinal protection and more studies need to be done. In one large study that compared patients who had cataract surgery, and different lenses placed inside the eye (one that filters blue light and one that doesn’t) there was no difference in the incidence of macular degeneration.
Blue Light And Sleep
There is more evidence to support that blue light disturbs sleep more than it disturbs your retina. A person’s circadian rhythm depends on exposure to light, especially blue light. Melatonin is secreted at night and helps us to fall asleep. If we are exposed to blue light the body thinks its not night time, and thus can disrupt your sleep. Artificial light tells the brain that it should not be making melatonin. This can thus disrupt your sleep patterns.
Can You Wear Blue Light Glasses All Day?
Because blue light glasses are protective, wearing them for extended periods of time should not cause any problems. If you don’t like wearing them all day, then you can just selectively wear them when you need to. There are limited studies that show that exposure to blue light may increase focus, but this is well supported. If you feel that your blue light glasses are not tolerable to wear for some reason then you should not wear them. The evidence is limited at this juncture, so be sure to ask your eye doctor if you have any specific questions.
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