Is Blue Light Harmful?
After staring at a computer for hours, who hasn’t felt like their eyes were tired and dry? But can the blue light given off by screens, smartphones and other digital sources actually cause damage to the eyes? According to the American Academy of Ophthalmology, there is currently no scientific evidence that blue light from electronics causes long-term damage.
Blue light can disrupt the body’s natural rhythms. When blue light comes from sunlight during the day, it gives us energy and stimulation. But exposure to blue light at night makes it hard to sleep if you’re glued to your phone, tablet or computer in the evening. A recent study showed that 90 percent of adults in the U.S. use an electronic device within one hour of bedtime at least a few nights per week. The blue light from your device can trick your brain into thinking it’s still daytime, causing it to suppress melatonin production, which is a natural sleep regulator that helps make you sleepy.
Blue light can also cause eye strain and dry eyes, which are reasons enough to limit exposure. Still others are concerned the long-term effects of screen exposure may still be unknown. In addition, children’s eyes absorb more blue light than adult eyes do, meaning they could be more at risk for vision issues in the future.
So, what should you think about blue light? We asked INTEGRIS Ophthalmologist Dr. Carl Sylvester for his best advice.
The blue light blues
"Blue light is just a wavelength of visible light. Most blue light comes from the sun, LED lights and fluorescent lights," Dr. Sylvester says. "Blue light itself doesn’t damage the eye any more than other light does." What does cause vision problems, however, is prolonged exposure to computer screens, tablets and other digital devices, which leads to eye strain, dry eyes, blurred vision and headaches. This is known as "computer vision syndrome," or CVS.
Officially, dry eye is a condition where a person doesn't have enough tears to lubricate the eye. Tears are necessary for maintaining eye health and providing clear vision, and dry eye can become a chronic problem, particularly in older adults.
Dr. Sylvester says he is seeing a big increase in CVS "because we are spending so much more time staring at screens, in which studies have shown that we blink half as much as we normally do. This close-up staring at computers for eight hours a day with reduced blinking can cause severe problems with dry eyes and digital eye strain."
What blue light doesn’t do is lead to damaged retinal cells or cause problems such as age-related macular degeneration. Macular degeneration affects more than 10 million Americans and is the leading cause of vision loss. This disorder affects more people than cataracts and glaucoma combined and is considered incurable.
"There is absolutely no scientific evidence that blue light causes macular degeneration, eye cancers or cataracts," Dr. Sylvester says. "But, we are seeing more people become near-sighted today than we did 50 years ago because they are staring at objects close-up for longer periods of time."
How to protect your eyes
Dr. Sylvester says there are steps you can take to decrease your exposure to blue light. Dr. Sylvester recommends taking breaks from the screen several times a day to help fight CVS.
"We call it the 20-20-20 rule," he says. "Every 20 minutes look at an object 20 feet away for 20 seconds." Dr. Sylvester also recommends closing your eyes or blinking on a regular basis and using artificial tears to combat dryness and fatigue.
For those still worried about blue light, it's a great idea to often unplug from your devices and reduce your screen time. Also, screen filters can reduce the amount of blue light given off from devices such as smartphones and tablets and are available in stores and online as are yellow-tinted computer glasses that are designed to block blue light when using the computer.