Blue Light and its affect on the eyes
Blue light has made headlines recently due to concerns that it could damage vision. Optical retailers Boots and Vision Express were busted by BBC One’s Watchdog programme. Investigators posing as shoppers caught salespeople overstating the dangers and using alarmist talk to con consumers into high-end lenses purported to protect your eyes from blue light. These undercover operations captured six health claims being made, none of which are backed up by evidence. Some claimed that blue light emitted from electronic devices can damage the eyes, while others said their lenses could prevent that damage. Like many sales tactics, this one piggybacks off of real science and frightens people who don’t have the specialized knowledge to separate fact from fiction. The inclusion of half-truths makes it easier to fool a well-educated person whose specialty isn’t optometry or ophthalmology. Understanding the truth about blue light will give you the necessary tools to protect your vision and your pocketbook.
What Is Blue Light?
Blue light is a perfectly normal and natural spectrum of light that is found in sunlight and light put out by electronic devices, LEDs, fluorescent lights and flat-screen televisions. The optometry community has already studied blue light and determined a safe exposure amount. Electronic devices only emit less than one percent of that safe exposure, meaning there is no harm in checking your email, watching a movie or enjoying a Youtube video.
The Dangers of Blue Light
When it comes to blue light, there is only one real danger: overexposure. Just as the human body isn’t built to run a marathon every day, we are not built to stare at a light source all day. If you are overexposed, there are a few issues that could arise.
Eye strain is a common issue for those who sit in front of a computer or television all day. This problem is known as digital eye strain and can induce headaches, migraines, nausea, tired eyes, increased tear production and blurry vision.
Snow blindness, also called photokeratitis, is a sunburn of the eyes. It’s painful and is usually caused by glaring natural light, such as sunlight on snow or water.
Overexposure to blue light is also linked to the acceleration of macular degeneration. This disease causes damage to the macula, which are the thin films on the centers of your retinas. As the damage gets worse, sharp central vision fades, leaving only peripheral vision intact.
Ocular cancer is also linked to overexposure. Just as too much sun exposure to your skin can cause melanoma, too much light exposure can cause ocular cancer. It’s a rare but dangerous form of cancer that is a serious risk, especially for those who live in bright, sunny locales.
Cataracts are also a concern. Cataracts cloud the crystalline lens of the eye, dimming vision and eventually requiring surgery. While there are many contributing factors to cataract formation such as age, smoking and genetics, overexposure to light is also to blame.
The Benefits of Blue Light
With all of the dangers above, you may think that living in a soothing, dim cave may be best for you. While low light is a great idea for relaxing and will help you to sleep at night, our bodies require sunlight and the accompanying blue light to produce vitamin D. Vitamin D allows us to absorb and use calcium, which is crucial for strong bones and teeth. In countries where daylight is short for much of the year, such as Norway, Russia and Canada, vitamin D deficiency can be a serious issue, leading to health problems. While drinking fortified milk and juice can help, natural exposure is the best prevention.
We also require light exposure to avoid emotional and psychiatric problems. Seasonal affective disorder (SAD) is characterized by depression that comes with winter and it can be crippling. General depression is also more common in areas that have a lot of gray days, such as the rainy Pacific Northwest in the United States. If you’re feeling down in the dumps, applying some sunscreen and taking a walk in the sun, even if it’s during cold weather, can help. If you’re still not feeling like your usual self, talk to your doctor or therapist about your concerns.
Protecting Yourself from Eye Damage
The first line of defense you have is to limit your exposure. Steps you can take include:
- Ditch the tanning bed. Tanning beds exposure you to dangerous levels of light. Even if you wear goggles to protect your eyes, your skin will pay the price. If you just can’t bring yourself to accept your porcelain glow, make the switch to self-tanner or spray tan.
- Cover up. If you spend time outdoors, wear sleeves, long pants and a wide-brimmed hat that keeps the sun off your face, neck and ears. The wide brim will also shade your eyes, protecting you from the glare and reducing the amount of light that enters your eyes.
- Change your schedule. Don’t make appointments that require you to drive into the sun, if possible. If you’re going to the beach or pool, avoid the hours between ten and three when the sun is at its worst. If you jog or hike, take advantage of the early morning and evenings for more privacy on the trails and less exposure.
- Make a schedule and stick to it. If you have a habit of sitting in front of your computer and mindlessly surfing, limit your time. If you want to enjoy the park on a sunny day, plan to arrive later in the afternoon to take advantage of the sunset and the cool, quiet twilight.
Your second line of defense is to protect your eyes when you are exposed. Some of the steps you can take to protect your eyes are:
- Wear sunglasses or coated lenses. This is where Boots and Vision Express were close but misleading. If you know you are going to be exposed to excessive blue light, wearing UV-blocking lenses can limit the amount entering your eyes and potentially causing damage. You won’t need sunglasses for the five-minute stroll to the corner store and back, but you will want protective lenses if you’re going to spend a day on the slopes or an entire night working on the computer.
- Take frequent breaks. Taking a break from the light exposure and allowing your eyes to rest and refocus can help avoid eye strain. Take a break every half hour while working at the computer. Look out a window and focus on a point in the distance and you’ll be able to feel your eyes relax.
- Install a blue light filter app on your devices. If you’re constantly on your phone or tablet, a blue light filter could help avoid eye strain. Of course, this is just a stopgap measure. You will still need to limit your time on devices and hold it away from your face to avoid eye strain.
- Get blue light blocking glasses. Computer glasses by Gunnar are available on Amazon for around £40 - £60 which block blue light. Gunnar glasses provide a small magnification as well. People with presbyopia can get prescription computer glasses as well.
Blue light does have the potential to cause harm to your vision if you are overexposed. Limiting your exposure and taking appropriate precautions when you are exposed are the best steps you can take to avoid light damage to your eyes.
Author: John Dreyer Optometrist Bsc(Hons), MCOPTOM, DipCLP
Created: 26 Jun 2017, Last modified: 4 Apr 2020