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If you’ve noticed Millennials at your local coffee shop sporting eyeglasses with an amber tint, you may have spotted blue light glasses in the wild.
Blue light blocking glasses look like regular vision glasses, but they’re designed to block potentially harmful light from digital screens. They may be all the rage these days (plus, they look cool), but do they work?
What are blue light glasses?
Blue light blocking glasses are just like your average, prescription-free eyeglasses, except they’re designed to filter out blue light.
The glasses have a yellow lens that reduces the amount of blue light that reaches your eyes while still enabling you to see other wavelengths of visible light (Lawrenson, 2017).
Manufacturers claim that blue light glasses can relieve symptoms of blue light exposure from using electronic devices, such as (Zhao, 2018; Downie, 2019):
- Dry eyes
- Eye fatigue
- Poor sleep quality
- Age-related macular degeneration
- Corneal and retinal damage
Wear blue light blocking glasses, companies say, and you’ll notice benefits like reduced eye strain and fatigue while working long hours on your laptop.
Other claims include fewer sleep issues after using electronics at night, as well as protecting your retinas from light-induced damage.
Do blue light glasses work?
How effective are blue light blocking glasses? The research is mixed.
Some studies have found that wearing blue light glasses may improve sleep quality in people who had trouble falling asleep (Leung, 2017; Lawrenson, 2017). In one small study, wearing blue light glasses for two hours before bed improved sleep symptoms for participants with insomnia, allowing them to fall asleep faster (Schecter, 2019).
Sleep hygiene: what is it and 20 tips for better sleep
Other studies found no demonstrable improvements to sleep from wearing them (Wahl, 2019; Lawrenson, 2017). There’s no objective evidence that the glasses help with eye strain, either.
So while they’re not necessarily going to help, there’s probably no harm in wearing them.
What is blue light?
The light we can see with our eyes ( the visible spectrum) can be divided up by wavelengths or color. Blue light falls on the short end of that spectrum.
Sunlight is the main source of blue light that we see every day, though much today is emitted by man-made instruments like computers, televisions, and smartphones, sometimes at high intensities (Leung, 2017; CDC, 2020).
Of all the colors in the electromagnetic rainbow, blue light has the biggest impact on our circadian rhythms.
Your circadian rhythm regulates all sorts of biological functions from hormone levels and body temperature to your sleep-wake cycle. It operates on a 24-hour cycle, in accordance with the sun––yet another clue to how impactful light is to our daily functioning (Wahl, 2019).
When our eyes perceive blue light, our brains react similarly to when we see sunlight. We become more alert, reaction times increase, and our mood improves (Downie, 2019; Wahl, 2019). These are great side effects during the day, but at night, too much blue light can keep our brains wired. Instead of falling asleep, we feel like staying awake (CDC, 2020).
Side effects of too much exposure to blue light
Research shows that blue light blocks the production of melatonin, the hormone responsible for helping you sleep.
Melatonin production is regulated by light exposure, and levels rise as the sun goes down. But when we expose ourselves to artificial light sources, it can mess with that mechanism, ultimately keeping melatonin levels low at night and throwing off your circadian rhythm.
Blue light exposure, especially at night, makes it harder to fall asleep. One review found that people who used devices at night had shorter periods of deep sleep and were less alert the next day (Wahl, 2019).
8 common sleep disorders: symptoms, causes, treatment
In addition to sleep issues, using digital devices can contribute to dry eyes, eye strain, and fatigue, as well as other symptoms of what’s called computer vision syndrome (Zhao, 2018).
Up to 90% of computer users report eye symptoms like eye strain, eye fatigue, dry eyes, headaches, and blurred vision (Rosenfield, 2011; Downie, 2019). We tend to blink less often when using a computer, and blinking serves to lubricate our eyes and keep debris out, but even reading printed material for extended periods can cause dry eyes.
Tips to reduce blue light exposure
Whether or not you believe the hype around blue light blocking glasses, it’s worth doing what you can to reduce digital eye strain. Follow these seven eye health tips, and your eyes will thank you.
1. Keep screens at arm’s length. Avoid holding your phone right up to your face, and keep computer screens at least two feet away from your eyes. When using a computer, look downwards into the screen rather than directly at it.
2. Follow the 20-20-20 rule. If you’ve never heard of this one, it’s easier than it sounds. Every 20 minutes, take a break and look at something 20 feet away for 20 seconds. You can set a reminder to keep you on track.
3. Reduce glare with a matte screen filter. Anti-glare screen filters reduce the glare coming from your computer screen. Plus, they protect your screen from dust and scratches, so you can help your eyes while keeping your workspace a little cleaner.
Shift work sleep disorder: symptoms, treatment
4. Use eye drops to relieve dryness. Available over-the-counter, lubricating eye drops (also known as artificial tears) can help moisten dry eyes that have had too much screen time.
5. Limit blue light at night. At night, dim the lights in your house. Use lamps with incandescent yellow bulbs. Yellow, red, and orange lights have little to no effect on your circadian rhythm. You can also invest in smart bulbs that adjust the concentration of blue light at night. If you use night lights in your house, choose ones with red instead of blue hues.
6. Reduce your screen time. Turn off electronics at least 30 minutes before bedtime. Before bed (or once it gets dark outside) turn on your device’s night mode. This blue light filter shifts your screen’s color hue to be more in the red spectrum, so it’s less disruptive to sleep. Dimming your phone’s brightness may help, too.
7. Get some sunshine. Get blue light the natural way by spending time outdoors or near a window during the day. Natural sunlight will help reset your circadian rhythm, especially if you get your dose of sunlight early in the morning. Focus on getting less artificial and more natural blue light, and you’ll find yourself sleeping easier.
If you feel that your vision quality is suffering, or you experience blurry vision, eye strain, or eye dryness for long periods, your best bet is to set up an appointment with your ophthalmologist.
- Centers for Disease Control and Prevention (CDC). (2020, April). The Color of the Light Affects the Circadian Rhythms. Retrieved July 14, 2021, from https://www.cdc.gov/niosh/emres/longhourstraining/color.html
- Downie, L. E., Keller, P. R., Busija, L., Lawrenson, J. G., & Hull, C. C. (2019). Blue‐light filtering spectacle lenses for visual performance, sleep, and macular health in adults. The Cochrane Database of Systematic Reviews, 2019(1), CD013244. doi: 10.1002/14651858.CD013244. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6353079/
- Lawrenson, J. G., Hull, C. C., & Downie, L. E. (2017). The effect of blue-light blocking spectacle lenses on visual performance, macular health and the sleep-wake cycle: a systematic review of the literature. Ophthalmic and Physiological Optics, 37(6), 644–654. doi: 10.1111/opo.12406. Retrieved from https://pubmed.ncbi.nlm.nih.gov/29044670/
- Leung, T. W., Li, R. W., & Kee, C. S. (2017). Blue-light filtering spectacle lenses: optical and clinical performances. PloS One, 12(1), e0169114. doi: 10.1371/journal.pone.0169114. Retrieved from https://pubmed.ncbi.nlm.nih.gov/28045969/
- Lockley, S. W., Brainard, G. C., & Czeisler, C. A. (2003). High sensitivity of the human circadian melatonin rhythm to resetting by short wavelength light. The Journal of Clinical Endocrinology and Metabolism, 88(9), 4502–4505. doi: 10.1210/jc.2003-030570. Retrieved from https://pubmed.ncbi.nlm.nih.gov/12970330/
- Rosenfield, M. (2011). Computer vision syndrome: a review of ocular causes and potential treatments. Ophthalmic and Physiological Optics, 31(5), 502–515. doi: 10.1111/j.1475-1313.2011.00834.x. Retrieved from https://pubmed.ncbi.nlm.nih.gov/21480937/
- Shechter, A., Kim, E. W., St-Onge, M. P., & Westwood, A. J. (2018). Blocking nocturnal blue light for insomnia: A randomized controlled trial. Journal of Psychiatric Research, 96, 196–202. doi: 10.1016/j.jpsychires.2017.10.015. Retrieved from https://pubmed.ncbi.nlm.nih.gov/29101797/
- Tosini, G., Ferguson, I., & Tsubota, K. (2016). Effects of blue light on the circadian system and eye physiology. Molecular Vision, 22, 61–72. Retrieved from https://pubmed.ncbi.nlm.nih.gov/26900325/
- Wahl, S., Engelhardt, M., Schaupp, P., Lappe, C., & Ivanov, IV. (2019). The inner clock—Blue light sets the human rhythm. Journal of Biophotonics, 12(12), e201900102. doi: 10.1002/jbio.201900102. Retrieved from https://onlinelibrary.wiley.com/doi/full/10.1002/jbio.201900102
- Zhao, Z. C., Zhou, Y., Tan, G., & Li, J. (2018). Research progress about the effect and prevention of blue light on eyes. International Journal of Ophthalmology, 11(12), 1999–2003. doi: 10.18240/ijo.2018.12.20. Retrieved from https://pubmed.ncbi.nlm.nih.gov/30588436/
Yael Cooperman is a physician and works as a Senior Manager, Medical Content & Education at Ro.