Lutein and Zeaxanthin: 2020 and Beyond
In Addition to Keeping Our Vision 20/20, These Nutrients Are Important for Brain and Skin Health, as Recent Research Highlights
If a multiple-choice test asked which organ the carotenoid lutein helps protect, and gave the options of the brain, eyes, or skin, many would select the eyes. Given lutein’s accumulation in the retina and other structures of the eye, we do see a preponderance of research related to this organ. However, high levels of lutein are also found in the brain and skin., Correspondingly, there has been substantial investigation into its impact on these organs, with many benefits being demonstrated., So, technically, the correct answer would be all of the above. Zeaxanthin, a carotenoid very similar in structure to lutein, also accumulates in the eye, brain, and skin;2,3 thus, it also offers these organs protection. With age and habits like smoking,3, levels of lutein and zeaxanthin (L/Z) decline, leaving the eyes, brain, and skin more susceptible to damage.
One reason that these molecules help protect the eyes is because they absorb light.1 In particular, they absorb light on the violet to blue end of the spectrum (~400 to 500 nm), which, incidentally, leads to their orangish-yellow appearance. Blue light damages the retina through a photo-oxidation reaction with lipofuscin, a mixture of lipids, proteins, and fluorescent compounds that are a byproduct of incompletely digested phagocytosed photoreceptor cells.7
With our digital technology–related increase in exposure to blue light that computer screens, digital devices, energy-efficient indoor lighting, and television screens emit, we see an increase in problems related to blue light exposure.
Lutein and zeaxanthin also quench singlet molecular oxygen, prevent lipid peroxidation, and induce nuclear factor erythroid 2-related factor 2 (Nrf2)–dependent antioxidant transcription.,,, They act as anti-inflammatories as well, and thus may be helpful in conditions such as uveitis, traumatic brain injury, or ischaemic stroke, in which substantial damage is also caused by inflammation. In acute settings such as these, higher levels of lutein prior to the event and administration afterwards may both be protective.,
Dietarily, we can increase our intake of L/Z by consuming dark green, leafy vegetables, with cooked kale and spinach both delivering more than 10 mg/100 g; eggs, with the yolk having the highest amounts of these nutrients; and pistachio nuts, which also deliver more than 1 mg/100 g. Other foods high in L/Z include orange peppers, squash, parsley, and romaine lettuce. Absorption of these carotenoids, which are fat-soluble nutrients, may be enhanced by the consumption with other fats, much like it is for other fat-soluble nutrients. For example, the consumption of a salad with fat-free dressing negligibly increases plasma carotenoid content, while consumption with 6 or 28 g of canola oil dose-dependently increases carotenoid content of the plasma. There is not a dietary guideline for lutein and/or zeaxanthin intake; however, research suggests that, to prevent macular degeneration, one should consume 6 mg of lutein and zeaxanthin a day. Yet dietary studies have shown that U.S. adults only consume 1 to 2 mg/day.
Herein, we take a look at the clinical studies using lutein, zeaxanthin, or a combination thereof, and the protection they offer for the eyes, brain, and skin.
As noted, one of the primary mechanisms by which L/Z help protect the eyes is by the absorption of blue light. Concentrated in the fovea, the central region of the macula where the density of cones is the greatest, the concentration of zeaxanthin is about 1,000 times higher than other tissues. Meso-zeaxanthin, a stereoisomer of zeaxanthin, is actually most central, being found at highest density in the epicenter of the macula. The highest concentration of zeaxanthin borders this, with lutein being highest more peripherally., Data suggests that a small amount of lutein is converted into meso-zeaxanthin in the macula;, however, it also may be present at low levels in supplements containing zeaxanthin.27
Dietary supplementation of lutein or L/Z has been shown to increase their levels not only in the serum but also in the macula, typically evaluated by assessment of macular pigment optical density (MPOD).,, Interestingly, in one study looking at L/Z in combination or both as monotherapies, it was shown that zeaxanthin, as a monotherapy, did not significantly impact macular levels.30 Increases in MPOD may depend on levels at baseline, with one study showing improvements only in the individuals having lower levels at baseline.
Because L/Z are fat-soluble antioxidants that gradually accumulate in their destination tissues, the duration of intervention prior to outcome evaluation is usually a minimum of two to six months;
however, residual effects have also been seen up to four months after cessation of the therapies. Increases in macular L/Z concentration correspond with a reduction in transmitted blue light.
Multiple studies have assessed how L/Z supplementation affects the vision of healthy individuals, typically evaluating the effect on visual acuity or symptoms related to intense light exposure (referred to as glare). With visual stressors such as the intense light of a camera flash, it takes some time for the eye to recover and there are aspects of discomfort. A higher MPOD is correlated with faster photostress recovery and reduced glare discomfort and disability., A correlation has been shown between low macular levels of L/Z and the development of age-related macular degeneration (AMD).6, Dietary intake studies also suggest this relationship, particularly in those with a high genetic risk of the condition.,,
In one randomised, double-blind, placebo-controlled trial, healthy subjects were supplemented with a combination of 10 mg of lutein and 2 mg of zeaxanthin or placebo daily for one year. Significant improvements in photostress recovery as well as chromatic contrast were seen with time, paralleling the time-related increase in MPOD. In another study in which participants received 10.5 mg of lutein and 0.96 mg of zeaxanthin daily for six months, those who had lower MPOD levels at baseline were more likely to respond to supplementation and experience a reduction in glare sensitivity.34 In a single-arm study, supplementation of 10 mg of lutein and 2 mg of zeaxanthin daily for six months also was shown to significantly improve visual performance under glare conditions.
Numerous additional studies have shown that supplementation with lutein, usually accompanied by a small amount of zeaxanthin at a 10:1 to 10:2 ratio, improves these and other aspects of vision in healthy adults. At doses of L/Z ranging from as little as 6 mg/day to 22 mg/day, improvements in vision have been seen as early as 45 days, although typically, assessment occurred after six months of supplementation.,,, Improvements in parameters related to night vision,44 contrast sensitivity,45,46 and global visual function46 were seen with regular, daily supplementation of L/Z.
Not surprisingly, the majority of human studies have looked at the effect that L/Z supplementation has on vision in individuals with AMD. In individuals with early AMD, supplementation of 20 mg lutein with 2 mg zeaxanthin for 12 months improved letter contrast sensitivity. In a longer, five-year study of patients with AMD, supplementation of L/Z (10 and 2 mg/day) significantly reduced the risk of progression to late AMD. It also reduced the risk of development of neovascular AMD in individuals with large drusen bilaterally, but not those who already had late AMD in one eye. In an additional assessment of the same population, it was found that L/Z supplementation significantly reduced the risk of needing cataract surgery in individuals in the lowest quintile of dietary L/Z intake. Three additional studies, having a duration of six months to two years, found that daily supplementation of 10 mg of lutein, with zeaxanthin ranging from 1 to 2 mg, significantly improved contrast sensitivity, and visual acuity.53,
It should be noted that in one of the studies finding improved contrast sensitivity,52 supplementation also included small amounts of vitamins B3, C, and E (as α-tocopherol); zinc; and copper, while in one of the studies showing improved visual acuity,54 supplementation included vitamins E and C; zinc; copper; and astaxanthin. Studies suggest there may be synergistic effects of the antioxidant vitamins with L/Z while astaxanthin, another member of the carotenoid family, also is known to benefit vision.7,,
Several studies have established that central nervous system (CNS) levels of lutein and zeaxanthin are related to brain function.,, Because the CNS levels of lutein and zeaxanthin can only be determined post mortem, this research primarily relies on evaluation of MPOD, which is correlated with L/Z levels in the brain (in humans and nonhuman primates) and can be measured noninvasively.2 In various populations, associations have been shown between MPOD or serum lutein levels and hippocampal function, visual-spatial and construction abilities, language ability, attention, processing speed, accuracy, mini-mental state examination scores, and general and fluid intelligence.,,,
In the fatty tissues of the CNS, the antioxidant protection that lutein and zeaxanthin offer to membranes is important for the health and function of neural plasma membranes, axonal projections, mitochondria, nuclear membranes, and myelin.12,, Levels of L/Z have been shown to be correlated with white matter integrity in several regions of the brain, including those that are vulnerable to cognitive decline. The cognitive impact of lutein has also been suggested to be related to docosahexaenoic acid (DHA) levels due to their colocalisation in several regions of the brain. In both the prefrontal cortex and striatum, mitochondrial lutein levels have been shown to be inversely related to DHA oxidation products, further pointing toward the interdependence of these nutrients.
In research pertaining to CNS function, supplementation of lutein and zeaxanthin is also implemented for a fairly long period prior to assessment, commonly with a ratio of 10:2 of lutein:zeaxanthin. In aging adults (with an average age of approximately 74), after supplementing with 12 mg of L/Z for a period of a year, significant improvements were seen in complex attention, cognitive flexibility, and composite memory (males only), with trends toward improvement in executive function domain.
In a study employing functional magnetic resonance imaging (fMRI) in aging individuals, after supplementation with 12 mg of L/Z for one year, fMRI showed increased internetwork connectivity, suggesting that rather than restoring brain function to a more youth-like state, capabilities may be enhanced by increased integration. A study of a similar population (using the same supplementation regime) found that those receiving L/Z had increased electroencephalogram (EEG) signal power when subject to a visual stimuli (steady-state visual evoked potential) at various flicker frequencies, suggesting that L/Z improved visual processing. Additionally, in individuals having a higher MPOD, increased EEG activation was seen at the highest frequencies.
One additional study in an aging population looked at the effects of a combination of L/Z with DHA. In this double-blind, placebo-controlled, multiple-arm study, women (from 60 to 80 years of age) were randomised to receive the combination of 12 mg of L/Z and 800 mg of DHA, 800 mg of DHA, 12 mg of L/Z, or placebo for a period of four months. Although all groups except placebo had significant improvements in verbal fluency, only those receiving the combination had significant improvements in memory scores and rate of learning, with trends toward more efficient learning also being seen.
Lutein and zeaxanthin are also important for the health of the skin. Here, they help protect against the damaging effects of another portion of the electromagnetic spectrum: ultraviolet (UV) light. Animal studies have shown that supplementation of lutein or L/Z reduces inflammation and edema, reactive oxygen species production, and epidermal hyperproliferation with exposure to UV-B radiation., When subject to routine exposure with UV-B light for 16 weeks, feed supplementation of L/Z significantly attenuated multiple parameters of photoaging as well as UV exposure–related tumour burden.75
But perhaps more interesting regarding L/Z and skin health is the protection they provide against the damaging effects of blue light as well. Although the damaging effects of the UV portion of the spectrum are well known, many people are less aware of the oxidative and DNA-damaging effects that blue light exposure also has on the skin.,, Blue light exposure even increases our production of melanin—which also suggests our body inherently knows to do the things that help protect us from it.
The magnitude of blue light damage to skin is less than what UV rays impart, but because of the regular exposure we have to blue light, and the lack of protection that sunscreen provides,5 blue light exposure not only causes its own damage, it renders us more susceptible to damage from the intense UV-A and UV-B rays as well. Damage from each of these forms of light is cumulative—which is why we see more signs of skin aging and skin cancer on light-exposed regions of our skin with increasing age.
Clinical studies have looked at the impact that oral, as well as topical, use of L/Z has on various parameters related to skin health. In one such randomized, double-blind, placebo-controlled study, healthy individuals with fair to olive skin that had mild to moderately dryness were supplemented with 12 mg of L/Z or placebo for a period of 12 weeks. The skin tone of individuals taking L/Z was significantly lightened and overall skin tone improved, perhaps indicative of the absorption of blue light and subsequent reduction of melanin production. In those taking L/Z, the minimal erythema dose (when subject to UV-A/UV-B light) and elastic recovery were significantly increased relative to baseline, and higher than those receiving placebo; however, the difference was not significant.
In another study, healthy women, age 25 to 50 years, were instructed to administer L/Z orally (10.5 mg), topically (a standardised dilution in butylene glycol), or topically and orally for a period of 12 weeks. Although the combination of topical and oral treatment typically had the greatest effects, both topical and oral treatment with L/Z led to a significant increase in skin lipids, hydration, elasticity, and minimal erythema dose, and a reduction in lipid peroxidation. Although there was an increase in skin lipids, questionnaires did not indicate subjects found their skin to be too oily, suggesting the increase may be attributable to things other than just sebaceous secretions, which often lead to such complaints.
Clearly, the benefits of supplementation with lutein and zeaxanthin cover more than just vision, giving many reasons for these carotenoids to be included in supplement protocols to support not just ocular function, but also brain and skin health, in 2020 and beyond.
 Krinsky NI, et al. Biologic mechanisms of the protective role of lutein and zeaxanthin in the eye. Annu Rev Nutr. 2003;23:171-201.
 Vishwanathan R, et al. Macular lutein and zeaxanthin are related to brain lutein and zeaxanthin in primates. Nutr Neurosci. 2013 Jan;16(1):21-9.
 Peng YM, et al. Concentrations and plasma-tissue-diet relationships of carotenoids, retinoids, and tocopherols in humans. Nutr Cancer. 1995;23(3):233-46.
 Erdman JW Jr, et al. Lutein and Brain Function. Foods. 2015 Dec;4(4):547-64.
 Roberts RL, et al. Lutein and zeaxanthin in eye and skin health. Clin Dermatol. 2009 Mar-Apr;27(2):195-201.
 Obana A, et al. Macular carotenoid levels of normal subjects and age-related maculopathy patients in a Japanese population. Ophthalmology. 2008 Jan;115(1):147-57.
 Roberts JE, Dennison J. The Photobiology of Lutein and Zeaxanthin in the Eye. J Ophthalmol. 2015;2015:687173.
 Cheng HM, et al. Does blue light filter improve computer vision syndrome in patients with dry eye. Life Science Journal. 2014;11(6):612-5.
 Rosenfield M. Computer vision syndrome (aka digital eye strain). Optometry in Practice. 2016 Feb 16;17(1):1-10.
 Fletcher AE, et al. Sunlight exposure, antioxidants, and age-related macular degeneration. Arch Ophthalmol. 2008 Oct;126(10):1396-403.
 Böhm F, et al. Interactions of dietary carotenoids with singlet oxygen (1O2) and free radicals: potential effects for human health. Acta Biochim Pol. 2012;59(1):27-30.
 Sujak A, et al. Lutein and zeaxanthin as protectors of lipid membranes against oxidative damage: the structural aspects. Arch Biochem Biophys. 1999 Nov 15;371(2):301-7.
 Frede K, et al. Lutein Activates the Transcription Factor Nrf2 in Human Retinal Pigment Epithelial Cells. J Agric Food Chem. 2017 Jul 26;65(29):5944-52.
 Zou X, et al. Zeaxanthin induces Nrf2-mediated phase II enzymes in protection of cell death. Cell Death Dis. 2014 May 8;5:e1218.
 Johnson EJ. Role of lutein and zeaxanthin in visual and cognitive function throughout the lifespan. Nutr Rev. 2014 Sep;72(9):605-12.
 He RR, et al. Antioxidant properties of lutein contribute to the protection against lipopolysaccharide-induced uveitis in mice. Chin Med. 2011 Oct 31;6(1):38.
 Tan D, et al. Lutein protects against severe traumatic brain injury through anti‑inflammation and antioxidative effects via ICAM‑1/Nrf‑2. Mol Med Rep. 2017 Oct;16(4):4235-40.
 Polidori MC, et al. Plasma carotenoid and malondialdehyde levels in ischemic stroke patients: relationship to early outcome. Free Radic Res. 2002 Mar;36(3):265-8.
 Jin XH, et al. Inhibitory effects of lutein on endotoxin-induced uveitis in Lewis rats. Invest Ophthalmol Vis Sci. 2006 Jun;47(6):2562-8.
 Li SY, et al. Lutein enhances survival and reduces neuronal damage in a mouse model of ischemic stroke. Neurobiol Dis. 2012 Jan;45(1):624-32.
 Eisenhauer B, et al. Lutein and Zeaxanthin-Food Sources, Bioavailability and Dietary Variety in Age-Related Macular Degeneration Protection. Nutrients. 2017 Feb 9;9(2).
 Brown MJ, et al. Carotenoid bioavailability is higher from salads ingested with full-fat than with fat-reduced salad dressings as measured with electrochemical detection. Am J Clin Nutr. 2004 Aug;80(2):396-403.
 Rasmussen HM, Johnson EJ. Nutrients for the aging eye. Clin Interv Aging. 2013;8:741-8.
 Mares-Perlman JA, et al. The body of evidence to support a protective role for lutein and zeaxanthin in delaying chronic disease. Overview. J Nutr. 2002 Mar;132(3):518S-524S.
 Landrum JT, et al. Analysis of zeaxanthin distribution within individual human retinas. Methods Enzymol. 1999;299:457-67.
 Bone RA, et al. Distribution of lutein and zeaxanthin stereoisomers in the human retina. Exp Eye Res. 1997 Feb;64(2):211-8.
 Nolan JM, et al. What is meso-zeaxanthin, and where does it come from? Eye (Lond). 2013 Aug;27(8):899-905.
 Johnson EJ, et al. Nutritional manipulation of primate retinas, III: Effects of lutein or zeaxanthin supplementation on adipose tissue and retina of xanthophyll-free monkeys. Invest Ophthalmol Vis Sci. 2005 Feb;46(2):692-702.
 Shyam R, et al. RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. Proc Natl Acad Sci U S A. 2017 Oct 10;114(41):10882-7.
 Schalch W, et al. Xanthophyll accumulation in the human retina during supplementation with lutein or zeaxanthin – the LUXEA (LUtein Xanthophyll Eye Accumulation) study. Arch Biochem Biophys. 2007 Feb 15;458(2):128-35.
 Arnold C, et al. Macular xanthophylls and ω-3 long-chain polyunsaturated fatty acids in age-related macular degeneration: a randomized trial. JAMA Ophthalmol. 2013 May;131(5):564-72.
 Richer S, et al. LAST II: Differential temporal responses of macular pigment optical density in patients with atrophic age-related macular degeneration to dietary supplementation with xanthophylls. Optometry. 2007 May;78(5):213-9.
 Obana A, et al. Changes in Macular Pigment Optical Density and Serum Lutein Concentration in Japanese Subjects Taking Two Different Lutein Supplements. PLoS One. 2015 Oct 9;10(10):e0139257.
 Rodriguez-Carmona M, et al. The effects of supplementation with lutein and/or zeaxanthin on human macular pigment density and colour vision. Ophthalmic Physiol Opt. 2006 Mar;26(2):137-47.
 Stringham JM, et al. Macular pigment and visual performance in glare: benefits for photostress recovery, disability glare, and visual discomfort. Invest Ophthalmol Vis Sci. 2011 Sep 22;52(10):7406-15.
 Hammond BR Jr, et al. Glare disability, photostress recovery, and chromatic contrast: relation to macular pigment and serum lutein and zeaxanthin. Invest Ophthalmol Vis Sci. 2013 Jan 17;54(1):476-81.
 Beatty S, et al. Macular pigment and risk for age-related macular degeneration in subjects from a Northern European population. Invest Ophthalmol Vis Sci. 2001 Feb;42(2):439-46.
 Ho L, et al. Reducing the genetic risk of age-related macular degeneration with dietary antioxidants, zinc, and ω-3 fatty acids: the Rotterdam study. Arch Ophthalmol. 2011 Jun;129(6):758-66.
 Tan JS, et al. Dietary antioxidants and the long-term incidence of age-related macular degeneration: the Blue Mountains Eye Study. Ophthalmology. 2008 Feb;115(2):334-41.
 Seddon JM, et al. Dietary carotenoids, vitamins A, C, and E, and advanced age-related macular degeneration. Eye Disease Case-Control Study Group. JAMA. 1994 Nov 9;272(18):1413-20.
 Hammond BR, et al. A double-blind, placebo-controlled study on the effects of lutein and zeaxanthin on photostress recovery, glare disability, and chromatic contrast. Invest Ophthalmol Vis Sci. 2014 Dec 2;55(12):8583-9.
 Stringham JM, Hammond BR. Macular pigment and visual performance under glare conditions. Optom Vis Sci. 2008 Feb;85(2):82-8.
 Pescosolido N, et al. The effect of night vision goggles on the retinocortical bioelectrical activity and its improvement by food supplement. Panminerva Med. 2012 Dec;54(1 Suppl 4):83-92.
 Loughman J, et al. The impact of macular pigment augmentation on visual performance using different carotenoid formulations. Invest Ophthalmol Vis Sci. 2012 Nov 29;53(12):7871-80.
 Kvansakul J, et al. Supplementation with the carotenoids lutein or zeaxanthin improves human visual performance. Ophthalmic Physiol Opt. 2006 Jul;26(4):362-71.
 Morganti P, et al. Protective effects of oral antioxidants on skin and eye function. Skinmed. 2004 Nov-Dec;3(6):310-6.
 Kawashima M, et al. Dietary Supplementation with a Combination of Lactoferrin, Fish Oil, and Enterococcus faecium WB2000 for Treating Dry Eye: A Rat Model and Human Clinical Study. Ocul Surf. 2016 Apr;14(2):255-63.
 Moshetova LK, et al. [Results of the use of antioxidant and angioprotective agents in type 2 diabetes patients with diabetic retinopathy and age-related macular degeneration]. Vestn Oftalmol. 2015 May-Jun;131(3):34-44.
 Sabour-Pickett S, et al. Supplementation with three different macular carotenoid formulations in patients with early age-related macular degeneration. Retina. 2014 Sep;34(9):1757-66.
 Age-Related Eye Disease Study 2 (AREDS2) Research Group, et al. Secondary analyses of the effects of lutein/zeaxanthin on age-related macular degeneration progression: AREDS2 report No. 3. JAMA Ophthalmol. 2014 Feb;132(2):142-9.
 Age-Related Eye Disease Study 2 (AREDS2) Research Group, et al. Lutein/zeaxanthin for the treatment of age-related cataract: AREDS2 randomized trial report no. 4. JAMA Ophthalmol. 2013 Jul;131(7):843-50.
 Wolf-Schnurrbusch UE, et al. Oral Lutein Supplementation Enhances Macular Pigment Density and Contrast Sensitivity but Not in Combination With Polyunsaturated Fatty Acids. Invest Ophthalmol Vis Sci. 2015 Dec;56(13):8069-74.
 Richer S, et al. Double-masked, placebo-controlled, randomized trial of lutein and antioxidant supplementation in the intervention of atrophic age-related macular degeneration: the Veterans LAST study (Lutein Antioxidant Supplementation Trial). Optometry. 2004 Apr;75(4):216-30.
 Piermarocchi S, et al. Carotenoids in Age-related Maculopathy Italian Study (CARMIS): two-year results of a randomized study. Eur J Ophthalmol. 2012 Mar-Apr;22(2):216-25.
 Wrona M, et al. Zeaxanthin in combination with ascorbic acid or alpha-tocopherol protects ARPE-19 cells against photosensitized peroxidation of lipids. Free Radic Biol Med. 2004 May 1;36(9):1094-101.
 Kidd P. Astaxanthin, cell membrane nutrient with diverse clinical benefits and anti-aging potential. Altern Med Rev. 2011 Dec;16(4):355-64.
 Lindbergh CA, et al. Lutein and Zeaxanthin Influence Brain Function in Older Adults: A Randomized Controlled Trial. J Int Neuropsychol Soc. 2018 Jan;24(1):77-90.
 Feeney J, et al. Low macular pigment optical density is associated with lower cognitive performance in a large, population-based sample of older adults. Neurobiol Aging. 2013 Nov;34(11):2449-56.
 Vishwanathan R, et al. Macular pigment optical density is related to cognitive function in older people. Age Ageing. 2014 Mar;43(2):271-5.
 Renzi LM, et al. Relationships between macular pigment optical density and cognitive function in unimpaired and mildly cognitively impaired older adults. Neurobiol Aging. 2014 Jul;35(7):1695-9.
 Cannavale CN, et al. Serum Lutein is related to Relational Memory Performance. Nutrients. 2019 Apr 2;11(4).
 Renzi LM, et al. The relation between serum xanthophylls, fatty acids, macular pigment and cognitive function in the Health ABC Study (abstract). FASEB J. 2008;22.
 Khan NA, et al. Macular Xanthophylls Are Related to Intellectual Ability among Adults with Overweight and Obesity. Nutrients. 2018 Mar 23;10(4).
 Crabtree DV, et al. Tubulins in the primate retina: evidence that xanthophylls may be endogenous ligands for the paclitaxel-binding site. Bioorg Med Chem. 2001 Aug;9(8):1967-76.
 Mohn E, et al. Distribution of lutein in membranes of rhesus macaque brain. The FASEB Journal. 2015 Apr;29(1_supplement):603-7.
 Mewborn CM, et al. Relation of Retinal and Serum Lutein and Zeaxanthin to White Matter Integrity in Older Adults: A Diffusion Tensor Imaging Study. Arch Clin Neuropsychol. 2018 Nov 1;33(7):861-74.
 Mohn ES, et al. Lutein and DHA co-localize in cell membranes of brain regions controlling cognition in the rhesus macaque. The FASEB Journal. 2016 Apr;30(1_supplement):689-2.
 Mohn E, et al. Lutein accumulates in subcellular membranes of brain regions in adult rhesus macaques: Relationship to DHA oxidation products. PLoS One. 2017 Oct 19;12(10):e0186767.
 Hammond BR Jr, et al. Effects of Lutein/Zeaxanthin Supplementation on the Cognitive Function of Community Dwelling Older Adults: A Randomized, Double-Masked, Placebo-Controlled Trial. Front Aging Neurosci. 2017 Aug 3;9:254.
 Lindbergh CA, et al. The effects of lutein and zeaxanthin on resting state functional connectivity in older Caucasian adults: a randomized controlled trial. Brain Imaging Behav. 2019 Jan 24.
 Norcia AM, et al. The steady-state visual evoked potential in vision research: A review. J Vis. 2015;15(6):4.
 Ceravolo SA, et al. Dietary Carotenoids Lutein and Zeaxanthin Change Brain Activation in Older Adult Participants: A Randomized, Double-Masked, Placebo-Controlled Trial. Mol Nutr Food Res. 2019 Aug;63(15):e1801051.
 Johnson EJ, et al. Cognitive findings of an exploratory trial of docosahexaenoic acid and lutein supplementation in older women. Nutr Neurosci. 2008 Apr;11(2):75-83.
 Lee EH, et al. Dietary lutein reduces ultraviolet radiation-induced inflammation and immunosuppression. J Invest Dermatol. 2004 Feb;122(2):510-7.
 González S, et al. Dietary lutein/zeaxanthin decreases ultraviolet B-induced epidermal hyperproliferation and acute inflammation in hairless mice. J Invest Dermatol. 2003 Aug;121(2):399-405.
 Nakashima Y, et al. Blue light-induced oxidative stress in live skin. Free Radic Biol Med. 2017 Jul;108:300-10.
 Dong K, et al. Blue light disrupts the circadian rhythm and create damage in skin cells. Int J Cosmet Sci. 2019 Dec;41(6):558-62.
 Bennet D, et al. An ultra-sensitive biophysical risk assessment of light effect on skin cells. Oncotarget. 2017 Jul 18;8(29):47861-75.
 Regazzetti C, et al. Melanocytes Sense Blue Light and Regulate Pigmentation through Opsin-3. J Invest Dermatol. 2018 Jan;138(1):171-8.
 Juturu V, et al. Overall skin tone and skin-lightening-improving effects with oral supplementation of lutein and zeaxanthin isomers: a double-blind, placebo-controlled clinical trial. Clin Cosmet Investig Dermatol. 2016 Oct 7;9:325-32.
 Palombo P, et al. Beneficial long-term effects of combined oral/topical antioxidant treatment with the carotenoids lutein and zeaxanthin on human skin: a double-blind, placebo-controlled study. Skin Pharmacol Physiol. 2007;20(4):199-210.
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