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The primary and natural source of blue light is the sun. As it shines during the day, its light signals for us to get up and go about our lives. When it sets, it heralds our time for slumber to rest our minds and bodies. We humans are designed to follow this pattern.
However, with advancements in technology, blue light has become ubiquitous. It is emitted by fluorescent and LED lighting, digital TVs, computer screens, and mobile devices. Now, our exposure to blue light is not only limited to the sun during the day but also continues well into the night through these technologies.
Overexposure to artificial blue light can be detrimental to us yet not many people know about it. In this article, we look at the negative effects of blue light and how to protect ourselves from it.
Blue Light Causes Digital Eye Strain
Viewing a digital screen is different from looking at ink on paper. Digital screens have lower contrast due to the blue light that they emit and produce glare making it more difficult to make out images or text. What this does is it makes the eyes work harder. This high visual demand is what causes digital eye strain. After logging in more than 2 hours on a screen your eyes will feel tired and your vision may get blurred. Other symptoms of digital eye strain are headaches; sore neck, shoulders, and back; and difficulty concentrating. In addition, blue light from screens makes your eyes dry. In fact, extended use of digital devices is the leading cause of eye strain.
Blue Light Damages Our Eyes
Studies have shown that blue light has adverse effects on our eyes. This is because our eyes are not equipped to block it. This coupled with the fact that blue light has high energy means that it can cause damage to our eyes. One effect of blue light on our eyes is the increased chance of developing cataracts. The lens of our eyes will try to filter anything harmful from reaching the sensitive retina at the back. By doing so, its cells develop yellowish pigments that act like blinds but it also makes the once clear lens decrease its transparency. It also increases our risk of age-related macular degeneration. Here, blue light destroys photoreceptor cells in the retina. Once this damage is done, it is irreversible and leads to blindness.
Blue Light Suppresses Sleep
Blue light is known to suppress our production of melatonin, the sleep hormone. Night time exposure to blue light can drop melatonin levels by 55% in five days. Test results also show that the participants took longer to fall asleep, had less restorative rapid eye movement (REM) sleep, and felt more groggy the next day. More than just losing sleep, blue light affects the quality of our sleep. So even if you log in the proper amount of sleep, you don’t feel rested the next day because of blue light exposure the night before. Poor sleep quality means that our bodies can’t recuperate properly which includes hindering the absorption of vitamins that sharpen our vision.