22/07/2022
With regular scrolling and swiping on social media, watching TV, reading work reports on your laptop, watching movies etc, It is safe to say most of us spend a lot of time staring at screens. And that can be bad for our eyes.
Blue light from electronics is linked to problems like blurry vision, eyestrain, dry eye, macular degeneration, and cataracts. Some people even have sleep issues.
What Is Blue Light?
It’s one of several colors in the visible light spectrum.
Red
Orange
Yellow
Green
Blue
Indigo
Violet
You may know them by the acronym ROY G BIV. Together, they make the white light you see when the sun -- the main source of blue light -- is shining. Fluorescent and LED (light-emitting diode) light bulbs also give off blue light.
Each color in the visible light spectrum has a different wavelength and energy level. Blue light has shorter wavelengths and higher energy than other colors. Some research shows a link between eye damage and short-wave blue light with wavelengths between 415 and 455 nanometers. Most of the light from the LEDs used in smartphones, TVs, and tablets has wavelengths between 400 and 490 nanometers (blue light).
Blue Light and Your Eyes
In large amounts, high-energy light from the sun -- like ultraviolet rays and blue light -- can boost your risk of eye disease. This has also raised concerns about blue light from digital devices and its effects on the eye.
Experts say digital eyestrain, or computer vision syndrome, (CVS), affects about 50% of computer users. Symptoms include dry eyes, irritated eyes and blurred vision.
Blue light is said to cause cataracts and other damages to the retina, by what is called phototoxicity. The amount of damage depends on wavelength and exposure time. Animal studies show even short exposure (a few minutes to several hours) may be harmful. A filter that cuts 94% of blue light has been shown to lessen damage.
There is evidence blue light could lead to permanent vision changes. Almost all blue light passes straight through to the back of your retina. Some research has shown blue light may increase the risk of macular degeneration, a disease of the retina.
Research shows blue light exposure may lead to age-related macular degeneration, or AMD. One study found blue light triggered the release of toxic molecules in photoreceptor cells. This causes damage that may lead to AMD.
Blue Light and Sleep
Screen time, especially at night, is linked to poor sleep. The blue light from electronic devices messes with your circadian rhythm, or sleep cycle. It signals your brain to wake up when it should be winding down. In one study, as little as 2 hours of exposure to blue light at night slowed or stopped release of the sleep hormone melatonin. Powering down your digital devices at least 3 hours before bedtime can help.
Blue Light and Kids
Your child’s eyes don’t filter blue light as well as yours do. Too much of it from device screens may raise their chances of developing obesity, nearsightedness, and attention focusing issues. At night, it may cause their body to release melatonin even more slowly than it does yours. To protect their eyes, limit your child’s screen time. And have them put all electronic devices, including handheld game devices, away at least a half hour before bedtime.
However, there are protective lenses against blue light, they are commonly called BLUE CUT lenses, Photochromic lenses also known as anti-glare lenses also offer some level of protection blue light effects.
Blue-Cut Lenses
Blue-cut lenses are designed to absorb anywhere from 10% to over 90% of blue light. Blue light is visible light with high energy in the range of 380 nanometers to 495 nanometers. This type of lens is designed to allow some blue light to pass through to prevent color distortion. The amount of color distortion may increase with lenses that are designed to block more than 50% or 60% of blue light from passing through to your eyes.
Anti-blue light glasses can immediately reduce symptoms of digital eye strain, especially when working at night. Over time, wearing blue blockers while working on digital devices may help to normalize your circadian rhythm and risk of macular degeneration
Anti-glare or anti-reflective lens coatings and blue cut lenses are helpful for reducing two of the most common causes of eyestrain. Depending on when you wear glasses, you may prefer lenses that reduce the amount of reflected light that reaches your eyes or lenses that have coatings or substrates that filter out a significant amount of blue light.
NB: The myopia institute says an estimated 50% of the world may be myopic by 2050. Currently about 90% of the Asian population have a level of myopia.
This is said to be as a result of increased near work and less outdoor activities.
Thus it is advised to give our phones and gadgets a break sometimes and be involved with outdoor activities.
https://myopiainstitute.org/myopia/
