Issue: Dec 2019
Protect Eyes from Screen-Time Damage
Computer and smart phone screens emit blue light that can cause degenerative eye disorders. Natural carotenoids have been shown to filter out blue light to ease eye strain and reduce risk of macular degeneration.
By Jason McNeil
Smartphones. Tablets. Computers. TVs. E-readers.
Screens are everywhere these days. And with them comes a danger that few people are aware of:
Most of them emit high amounts of harmful blue light.1
This blue light can cause problems like digital eye strain and insomnia.
Even more worrisome, it can damage the retina, the part of the eye that captures light and sends signals to the brain, allowing you to see.2-7
This damage increases the risk for macular degeneration, a leading cause of blindness in older adults.8-11
Disconnecting from modern technology isn’t exactly an option.
Fortunately, scientists have discovered that two nutrients, lutein and zeaxanthin, filter out the most dangerous wavelengths of blue light, acting almost like internal sunglasses.
Increasing intake of these plant pigments shields the retina, reducing risk of eye strain and age-related eye disease.12
The results can be dramatic: One study found that people with the highest dietary intake of lutein and zeaxanthin had a 41% lower risk of developing advanced macular degeneration.13
The Growing Problem of Screen Time
Roughly 96% of Americans own a cellphone. A vast majority also own a desktop or laptop computer, and many have tablets, e-readers, and LED televisions, as well.14
These devices are used almost constantly—for work, play, entertainment, and research.15,16
One study found that average users check their smartphones about 52 times per day.17 And at least two different, recent studies have shown that the average adult in the U.S. spends more than nine hours a day looking at digital media.18,19
The blue light emitted from most of these devices can cause three problems:
Digital Eye Strain
Staring at blue-light-emitting screens for long periods of time can cause digital eye strain, which often manifests as eye pain, dry eyes, headache, and blurred vision.15
This condition (once known as computer vision syndrome) is becoming more common as people spend more time looking at screens. A few years ago, it was estimated that 65% of people in the U.S. have symptoms of digital eye strain, and this number is growing.15
Being exposed to sunlight during the day and darkness at night helps set our circadian rhythm, the natural internal clock that regulates sleep-wake cycles. The sun’s blue light is an important contributor to these circadian rhythms.
But with increasing screen time, we are exposed to intense blue light well into the evening. To our brains, it’s as though the sun is still blazing, even at night.
This dramatic change in light-dark cycles can impair normal circadian rhythms. As a result, the body produces less melatonin at night,4 leading to difficulty falling asleep and insomnia. This loss of sleep can cause drowsiness and problems with attention and alertness.20
Risk for Macular Degeneration
The biggest danger of excess blue-light exposure is that it can permanently damage vision.
When blue-light wavelengths hit the retina, they set off a cascade of chemical reactions that damage photoreceptors, the retinal cells responsible for first detecting light.2,3,5-7,21
The result can be impairment of photoreceptor function and even cell death. Photoreceptors are not yet replaceable, and without them, vision is not possible.
In fact, several studies now confirm that chronic exposure to blue light increases the risk of age-related macular degeneration, 2,8-10 a leading cause of blindness.11
What You Need to Know
SHIELDING YOUR EYES FROM BLUE-LIGHT DAMAGE
- Digital screens emit a high percentage of blue light, a major contributor to digital eye strain, sleep problems, and the development of age-related macular degeneration, a major cause of vision loss in older adults.
- The carotenoid pigments lutein and zeaxanthin are concentrated in the retina of the eye, where they help shield it from the harmful effects of blue light.
- Most people have levels of these carotenoids that are far below what is recommended by doctors for optimal protection.
- Increasing intake of lutein and zeaxanthin from marigold extract has been shown to significantly boost retinal levels of these pigments, protecting against eye strain and reducing the risk for macular degeneration and vision loss.
The retina of the eye has a built-in shield to protect photoreceptors from blue-light damage. The retinal pigment epithelium has extremely high concentrations of the carotenoids lutein and zeaxanthin, along with a slightly different form of zeaxanthin called meso-zeaxanthin.3
These pigments help catch and disperse the energy of blue light, significantly reducing the amount that hits the photoreceptors.3,22-25 Carotenoids also have free-radical scavenging and anti-inflammatory properties, further reducing damage that leads t.3,22,25,26
But there’s a problem: Lutein and zeaxanthin aren’t created in the human body. They’re produced in plants and must be obtained from the diet or by supplementation.27
Modern Western diets are so lacking in carotenoids that the levels of lutein and zeaxanthin in most people’s retinas are far below what are considered optimal to protect vision.27,28
The carotenoids in the retina can be estimated by measuring the macular pigment optical density. (The macula is the central area of the retina.) The higher the density, the more carotenoids present, and more blue light is blocked.
The average macular pigment optical density in people from Western countries is about 0.3. Eye health experts agree that optical density measurements above 0.5 are ideal and most protective against blue-light-induced visual injury.29,30
The good news: Increasing intake of lutein and zeaxanthin directly leads to greater macular pigment optical density.31-38
One study evaluated a carotenoid formula derived from the marigold plant, containing 10 mg of lutein and 2 mg of zeaxanthin isomers (zeaxanthin and meso-zeaxanthin).37 Subjects taking the carotenoids for 12 months saw their macular pigment optical density increase from below the recommended level up to a healthy range, an average of 0.654.
Lutein and Zeaxanthin Protect Your Eyes
Several human studies have shown that increasing intake of lutein and zeaxanthin isomers (zeaxanthin and meso-zeaxanthin) improves visual function by reducing glare, improving contrast sensitivity, and protecting against visual problems associated with bright lights.37-39
Even more striking, taking these carotenoids has been shown to slow the progression of age-related macular degeneration and improve visual acuity (the clarity or sharpness of vision) in those who already have symptoms of the disorder.31,33-35,40,41
One study of 102,000 people aged 50 and older, conducted over 20 years, found that those with the highest intake of lutein and zeaxanthin had a 41% lower risk of progressing to advanced macular degeneration.13
Digital screens emit a high level of potentially dangerous blue light, which can contribute to eye strain and sleep problems.
They are toxic to cells in the retina of the eye, contributing to loss of vision through age-related macular degeneration.
Carotenoid pigments lutein and zeaxanthin defend against blue-light-induced eye problems. But most people don’t get enough from their diets to provide optimal protection.
A marigold extract has been incorporated into a sugar-free gummy that contains these carotenoids at doses that have proven effective in clinical trials.
Studies have shown that increasing intake of these nutrients boosts the eye’s natural defenses against blue light, shielding against eye strain and long-term damage which can lead to macular degeneration.
- Available at: https://www.reviewsce.com/ce/the-lowdown-on-blue-light-good-vs-bad-and-its-connection-to-amd-109744. Accessed August 1, 2019, 2019.
- Alaimo A, Linares GG, Bujjamer JM, et al. Toxicity of blue led light and A2E is associated to mitochondrial dynamics impairment in ARPE-19 cells: implications for age-related macular degeneration. Arch Toxicol. 2019 May;93(5):1401-15.
- Bian Q, Gao S, Zhou J, et al. Lutein and zeaxanthin supplementation reduces photooxidative damage and modulates the expression of inflammation-related genes in retinal pigment epithelial cells. Free Radic Biol Med. 2012 Sep 15;53(6):1298-307.
- Available at: https://www.forbes.com/sites/fionamcmillan/2018/08/11/how-blue-light-damages-cells-in-your-eyes/#6a1cb8f1384b. Accessed August 1, 2019, 2019.
- Nakamura M, Kuse Y, Tsuruma K, et al. The Involvement of the Oxidative Stress in Murine Blue LED Light-Induced Retinal Damage Model. Biol Pharm Bull. 2017;40(8):1219-25.
- Ratnayake K, Payton JL, Lakmal OH, et al. Blue light excited retinal intercepts cellular signaling. Sci Rep. 2018 Jul 5;8(1):10207.
- Sparrow JR, Boulton M. RPE lipofuscin and its role in retinal pathobiology. Exp Eye Res. 2005 May;80(5):595-606.
- Algvere PV, Marshall J, Seregard S. Age-related maculopathy and the impact of blue light hazard. Acta Ophthalmol Scand. 2006 Feb;84(1):4-15.
- van der Burght BW, Hansen M, Olsen J, et al. Early changes in gene expression induced by blue light irradiation of A2E-laden retinal pigment epithelial cells. Acta Ophthalmol. 2013 Nov;91(7):e537-45.
- Wielgus AR, Collier RJ, Martin E, et al. Blue light induced A2E oxidation in rat eyes–experimental animal model of dry AMD. Photochem Photobiol Sci. 2010 Nov;9(11):1505-12.
- Congdon N, O’Colmain B, Klaver CC, et al. Causes and prevalence of visual impairment among adults in the United States. Arch Ophthalmol. 2004 Apr;122(4):477-85.
- Lawler T, Liu Y, Christensen K, et al. Dietary Antioxidants, Macular Pigment, and Glaucomatous Neurodegeneration: A Review of the Evidence. Nutrients. 2019 May 1;11(5).
- Wu J, Cho E, Willett WC, et al. Intakes of Lutein, Zeaxanthin, and Other Carotenoids and Age-Related Macular Degeneration During 2 Decades of Prospective Follow-up. JAMA Ophthalmol. 2015 Dec;133(12):1415-24.
- Available at: https://www.pewinternet.org/fact-sheet/mobile/. Accessed August 29, 2019.
- The Vision Council. Eyes Overexposed: The Digital Device Dilemma – 2016 Digital Eye Strain Report. The Vision Council;2016.
- Available at: https://www.pewresearch.org/fact-tank/2019/07/25/americans-going-online-almost-constantly/. Accessed August 1, 2019, 2019.
- Available at: https://www2.deloitte.com/us/en/pages/technology-media-and-telecommunications/articles/global-mobile-consumer-survey-us-edition.html. Accessed Sept. 4, 2019,
- Available at: https://www.nielsen.com/us/en/insights/report/2019/q3-2018-total-audience-report/. Accessed August 29, 2019.
- Rosenfield M. Computer vision syndrome (a.k.a. digital eye strain). Optometry in Practice. 2016;17(1):1-10.
- Touitou Y, Reinberg A, Touitou D. Association between light at night, melatonin secretion, sleep deprivation, and the internal clock: Health impacts and mechanisms of circadian disruption. Life Sci. 2017 Mar 15;173:94-106.
- Ham WT, Jr., Mueller HA, Ruffolo JJ, Jr., et al. Basic mechanisms underlying the production of photochemical lesions in the mammalian retina. Curr Eye Res. 1984 Jan;3(1):165-74.
- Chucair AJ, Rotstein NP, Sangiovanni JP, et al. Lutein and zeaxanthin protect photoreceptors from apoptosis induced by oxidative stress: relation with docosahexaenoic acid. Invest Ophthalmol Vis Sci. 2007 Nov;48(11):5168-77.
- Loskutova E, Nolan J, Howard A, et al. Macular pigment and its contribution to vision. Nutrients. 2013 May 29;5(6):1962-9.
- Strauss O. The retinal pigment epithelium in visual function. Physiol Rev. 2005 Jul;85(3):845-81.
- Xue C, Rosen R, Jordan A, et al. Management of Ocular Diseases Using Lutein and Zeaxanthin: What Have We Learned from Experimental Animal Studies? J Ophthalmol. 2015;2015:523027.
- Kijlstra A, Tian Y, Kelly ER, et al. Lutein: more than just a filter for blue light. Prog Retin Eye Res. 2012 Jul;31(4):303-15.
- Beatty S, Nolan J, Kavanagh H, et al. Macular pigment optical density and its relationship with serum and dietary levels of lutein and zeaxanthin. Arch Biochem Biophys. 2004 Oct 1;430(1):70-6.
- Coleman HR, Chan CC, Ferris FL, 3rd, et al. Age-related macular degeneration. Lancet. 2008 Nov 22;372(9652):1835-45.
- Bernstein PS, Delori FC, Richer S, et al. The value of measurement of macular carotenoid pigment optical densities and distributions in age-related macular degeneration and other retinal disorders. Vision Res. 2010 Mar 31;50(7):716-28.
- Iannaccone A, Mura M, Gallaher KT, et al. Macular pigment optical density in the elderly: findings in a large biracial Midsouth population sample. Invest Ophthalmol Vis Sci. 2007 Apr;48(4):1458-65.
- Akuffo KO, Nolan JM, Howard AN, et al. Sustained supplementation and monitored response with differing carotenoid formulations in early age-related macular degeneration. Eye (Lond). 2015 Jul;29(7):902-12.
- Berrow EJ, Bartlett HE, Eperjesi F. The effect of nutritional supplementation on the multifocal electroretinogram in healthy eyes. Doc Ophthalmol. 2016 Apr;132(2):123-35.
- Huang YM, Dou HL, Huang FF, et al. Effect of supplemental lutein and zeaxanthin on serum, macular pigmentation, and visual performance in patients with early age-related macular degeneration. Biomed Res Int. 2015;2015:564738.
- Huang YM, Dou HL, Huang FF, et al. Changes following supplementation with lutein and zeaxanthin in retinal function in eyes with early age-related macular degeneration: a randomised, double-blind, placebo-controlled trial. Br J Ophthalmol. 2015 Mar;99(3):371-5.
- Ma L, Dou HL, Huang YM, et al. Improvement of retinal function in early age-related macular degeneration after lutein and zeaxanthin supplementation: a randomized, double-masked, placebo-controlled trial. Am J Ophthalmol. 2012 Oct;154(4):625-34 e1.
- Ma L, Liu R, Du JH, et al. Lutein, Zeaxanthin and Meso-zeaxanthin Supplementation Associated with Macular Pigment Optical Density. Nutrients. 2016 Jul 12;8(7).
- Stringham JM, O’Brien KJ, Stringham NT. Macular carotenoid supplementation improves disability glare performance and dynamics of photostress recovery. Eye Vis (Lond). 2016;3:30.
- Stringham JM, Stringham NT. Serum and retinal responses to three different doses of macular carotenoids over 12 weeks of supplementation. Exp Eye Res. 2016 Oct;151:1-8.
- Nolan JM, Power R, Stringham J, et al. Enrichment of Macular Pigment Enhances Contrast Sensitivity in Subjects Free of Retinal Disease: Central Retinal Enrichment Supplementation Trials – Report 1. Invest Ophthalmol Vis Sci. 2016 Jun 1;57(7):3429-39.
- Liu R, Wang T, Zhang B, et al. Lutein and zeaxanthin supplementation and association with visual function in age-related macular degeneration. Invest Ophthalmol Vis Sci. 2014 Dec 16;56(1):252-8.
Wei CX, Sun A, Yu Y, et al. Challenges in the Development of Therapy for Dry Age-Related Macular Degeneration. Adv Exp Med Biol. 2016;854:103-9.