How Blue Light Affects Your Eyes
Conflicting information in the media about blue light may make you wonder if you need to be concerned about the potential dangers of this type of light. The truth is blue light can be harmful and helpful.
What Is Blue Light?
The sun produces a rainbow of colors. Yellow, green, violet, red, orange, and blue light all make up the colors in the visible light spectrum. Blue light, located at one end of the spectrum, produces short wavelengths at a high level of energy. Red light, at the opposite end of the visible light spectrum, has longer, less energetic wavelengths. The other colors fall between these two extremes.
The sun isn't the only source of blue light. Televisions, digital device screens, and fluorescent and LED light bulbs also produce high levels of blue light.
Blue Light Benefits
Blue light is essential for:
- Brain Function. Exposure to blue light is important for memory, thinking, and processing information. Blue light also helps you stay alert.
- Sleep. Blue light plays a crucial role in your sleep/wake cycle.
- Improves Mood. Blue light has a natural pick-me-up effect on your mood.
- Vision. Blue light exposure from the sun is necessary for vision development in children and could reduce the likelihood of developing myopia (nearsightedness). Adults who spent more time outdoors as children had a lower myopia risk in adulthood, according to a research study published in Scientific Reports.
Potential Dangers of Blue Light
Blue light exposure from digital devices may or may not be a factor in eye diseases, depending on which expert or report you follow. An August 2022 review published in Heliyon summarized recent studies on the effects of blue light on the eyes. The review evaluated several eye diseases or symptoms thought to be associated with blue light exposure, including:
- Dry Eye. Increased exposure to blue light in mice caused cell death and oxidative damage to the cornea, the clear layer of tissue over the iris and pupil in one study. Although these results might mean that blue light exposure could trigger dry eye symptoms in humans, some researchers aren't so sure that there is a link between dry eye and blue light. They noted that other factors, including the reduced rate of blinking when using digital screens, could also be responsible for dry eye.
- Eyestrain. Several studies conducted on the effects of blue-filtering lenses on dry eye didn't detect any difference in dry eye symptoms when participants wore the lenses. Research subjects in one dry eye study did notice less eyestrain when wearing high-filtering blue lenses, while higher reading speeds were a benefit of blue-filtering lenses in another study.
- Cataracts. Exposure to sunlight increases your risk for developing cataracts, an eye condition that occurs when the clear lens inside your eye becomes cloudy. Researchers are unsure if blue light exposure affects your cataract risk.
- Macular Degeneration. Years of sun exposure could raise your risk for developing macular degeneration, an eye disease that causes blurred vision or blank spots in your central vision. Some researchers believe that blue light might worsen your macular degeneration risk. Others think that the blue light produced by digital devices isn't strong enough to damage the macula.
Obviously, researchers are still learning about the possible effects of blue light on the eyes. Additional research studies will provide more information that will help us make wise choices about blue light exposure.
Until we learn more about blue light, it makes sense to:
- Wear Sunglasses Year-Round. Sunglasses block blue light and ultraviolet A (UVA) and ultraviolet B (UVB) rays from entering your eyes. When shopping for sunglasses, look for styles that offer 100% protection from the sun's rays.
- Use Blue Light-Filtering Glasses. Blue-light filtering lenses may keep your eyes more comfortable when you're using your computer or other digital devices. The glasses are available in both prescription and non-prescription varieties.
- Visit Your Vision Therapist if You Experience Eyestrain When Using Digital Devices. Although anyone can develop digital eyestrain, it's more likely to happen if you have strabismus (misaligned eyes) or amblyopia (lazy eye), or focusing, eye teaming, or eye tracking problems. Vision therapy can improve those conditions and help relieve your eyestrain symptoms.
Are you struggling with eyestrain, headaches, and fatigue when using digital devices? Vision therapy could make using the devices much more comfortable. Contact our office to schedule an appointment for a comprehensive eye exam.
Sources:
Nature: Scientific Reports: Time Spent Outdoors in Childhood Is Associated with Reduced Risk of Myopia as an Adult, 3/18/2021
https://www.nature.com/articles/s41598-021-85825-y
Heliyon: A Review of the Current State of Research on Artificial Blue Light Safety as It Applies to Digital Devices, 8/15/2022
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9420367/
American Academy of Ophthalmology: Digital Devices and Your Eyes, 10/27/2022
https://www.aao.org/eye-health/tips-prevention/digital-devices-your-eyes