Antioxidants have become all the rage lately. Whether it's for helping to reduce inflammation, protect the brain, boost the immune system, or whatever else have you, they're everywhere.
But there's a good reason for their popularity.
Backed by hundreds of scientific studies, antioxidants are a powerhouse when it comes to protecting the body from harm, especially the eyes.
Regarding eye health, however, there's one antioxidant we prize: lutein. It's found in an abundance of colorful fruits and vegetables, and more recently in many eye support supplements.
If you've never heard of it before, you're about to learn everything you need to know—what it is, how it benefits the eyes, where you can find it, and the important points on lutein safety.
What Is Lutein?
Lutein is a type of antioxidant known as a carotenoid. Ever heard of beta-carotene? That's another type of carotenoid found in many orange-colored foods that's beneficial for many reasons.
And despite there being over 850 discovered carotenoids, very few are actually present in human tissue 1. That is, except for lutein and its isomers.
Lutein is a yellow carotenoid found in many colorful fruits and vegetables, but also in a few animal foods.
It's gained much attention recently for its role in visual performance and reducing the risk of age-related macular degeneration (AMD), but interestingly, it's also the predominant carotenoid in human brain tissue 2.
The Role Of Lutein In Eye Health
Generally speaking, you'll often find two antioxidants together—lutein and zeaxanthin, as well as smaller amounts of meso-zeaxanthin.
Zeaxanthin and meso-zeaxanthin are isomers of lutein and fellow carotenoids that both play a pivotal role in supporting the eyes' health. They're basically the power couple of antioxidants for eye health.
Lutein and its isomers are the only carotenoids that accumulate in the fovea of the human retina and make up macular pigment 3.
The macula lies in the central retina, in the posterior part of the eye, and plays a significant role in visual acuity and central vision due to its high concentration of photoreceptor cells 1.
The three carotenoids are found in the highest concentrations in the macula, with lutein present at the highest quantity in the periphery, zeaxanthin in the mid-periphery, and meso-zeaxanthin in the epicenter 1.
Together, they form the retinal macular pigment, which is important for maintaining optimal visual performance.
Lutein is also found in the eye's lens and protects the lens against age-related diseases like cataracts.
It's been shown that these carotenoids play a role in the visual system and increased dietary intake of lutein and zeaxanthin appears to raise serum concentrations and macular pigment density; this is associated with improved visual function and a reduced risk of developing ocular conditions like age-related macular degeneration (AMD) 2.
Learn more about zeaxanthin side effects and benefits.
Benefits Of Lutein
Blue Light Absorption
The ability of lutein and its isomers to absorb blue light rays is perhaps one of the most well-established benefits of lutein. Compared with other carotenoids, lutein exhibits the highest efficacy for absorbing rays because of the orientation of its liposomal membrane 4.
Immediate accessibility of devices with screens (smartphones, laptops, tablets, TVs, etc.) and LED lamps mean we're constantly exposed to blue light.
While blue light rays are naturally emitted from the sun, they come primarily from devices at a high-energy wavelength of 450-295nm.
Because of this high energy, it's capable of triggering free radical formation and inducing oxidative stress on the eyes, thus increasing the risk of various ocular conditions.
Interestingly though, the peak wavelength of lutein's absorption is around 460nm—directly in the middle of blue light's wavelength, which means lutein can effectively decrease possible light-induced damage by absorbing anywhere from 40 to 90% of blue light 5.
Because the fovea contains the highest concentration of lutein, as well as rod and cone photoreceptors, the photoreceptors are protected from light-induced damage.
Antioxidant Properties
When reactive oxygen species (ROS, free radical) production overwhelms the cellular antioxidant defenses, cells become subject to oxidative stress, which has been implicated in the pathogenesis of a number of ocular diseases including cataracts, uveitis, retinal degeneration, and more 6.
The two hydroxyl groups in lutein make it more polar and hydrophilic (attracted to water) than other carotenoids, which means it is better suited to react with oxygen and act as an antioxidant by effectively scavenging reactive oxygen species 1.
Lutein is capable of reacting with these ROS to reduce cellular damage caused by these radicals effectively. In doing so, the radical becomes stable and is no longer capable of causing damage to cellular structures.
Reduces Inflammation
Lutein may also hold promise as a potent anti-inflammatory. Research suggests that lutein may inhibit the action of pro-inflammatory molecules, including COX2 and NF-kB.
The proposed mechanism behind its anti-inflammatory action is its ability to prevent increased inflammatory cytokines and the upregulation of inflammation-related gene expression 7.
As inflammation is a key mechanism behind many ocular diseases, lutein's anti-inflammatory property could make it an effective treatment for reducing the severity of several conditions.
Reduces The Risk of Ocular Conditions
Human studies show a promising link between lutein and ocular conditions.
Here's what the research shows 8-13:
- Age-related macular degeneration (AMD): The role of lutein in preventing progression of AMD is still unclear, however, early studies suggested that higher blood levels of antioxidants, especially carotenoids like lutein, may reduce the risk of AMD. Further evaluation found that high plasma levels of lutein and zeaxanthin could elicit up to a 79% risk reduction of age-related maculopathy compared with lower levels.
- Diabetic retinopathy: Clinical studies show that lutein and zeaxanthin supplementation can improve retinal thickness and function, which indicates the protective effects of lutein on vision in diabetics. In rodent studies, lutein may help reduce oxidative stress, confirmed by a decrease in extracellular signal-regulated kinase (ERK) activation and brain-derived neurotrophic factor (BDNF), along with an increase in glutathione (GSH) and glutathione peroxidase (GPx).
- Cataracts: Lutein's effect on cataracts has been controversial to date, but some research suggests that lutein supplementation can reduce the formation of cataracts upwards of 40%.
While not an inclusive list, there's a growing body of evidence to support the benefit of lutein on many eye conditions.
Where Can You Find It?
With all of that being said, a diet with a good variety of foods is often rich in lutein. It can be found in both plant-based foods and animal ones, with egg yolks being one of the richest lutein sources on a per weight basis.
Maybe it's just us, but it seems a little convenient that eggs have a slight resemblance to eyes and they just so happen to be good for them!
If you follow a plant-based diet, not to worry. Lutein is abundant in a variety of plant foods, including 14:
- Paprika
- Dandelion
- Pepper
- Chicory
- Radicchio
- Leafy greens (kale, cress, spinach, chard, collards, mustard greens, turnip greens, arugula)
- Basil
- Parsley
However, keep in mind that like other carotenoids, the bioavailability of lutein increases when consumed with fat 15, so always eat your veggies with a healthy fat source like avocado, nuts, seeds, butter, or oil (coconut, avocado, olive).
As well, the lutein in eggs appears to be more bioavailable than that from plant-based sources or supplements 16.
If you want to take it a step further, supplement a lutein-rich diet with a high quality, highly bioavailable supplement Performance Lab Vision.
Being one of the best and most effective vision supplements on the market, it provides more than just lutein to support your eyes.
Vision is a formula of six potent antioxidants designed for sharp, crystal-clear visual performance and overall eye health.
It combines lutein and zeaxanthin with freeze-dried blackcurrant and blackcurrant extract, bilberry extract, astaxanthin, and saffron to:
- Strengthen the natural eye defenses
- Enhance visual acuity
- Boost contrast sensitivity
- Protect the eyes from macula-damaging blue light rays
- Sharpen vision and support proper blood flow to the eyes
- Enhance motion detection
- Reduce glare
Is It Safe?
Now that you understand why lutein is such an excellent supplement for your eyes, let's talk a bit about its safety.
There isn't a substantial amount of research indicating the optimal dosage of lutein, but there's plenty of research to suggest that it has a relatively high safety profile; the US Food and Drug Administration (FDA) also categorizes it Generally Regarded as Safe (GRAS) 17.
In general, studies administer between 1-2mg of lutein per day, but even still, these levels are substantially lower than the administered amount in the AREDS2 study published in 2013, where participants received a daily dose of 10mg of lutein daily to test the effects on AMD.
The Council for Responsible Nutrition (CRN) reports lutein intake up to 20mg per day is safe with no reported side effects. In comparison, other studies have administered up to 30mg daily with no adverse health effects or signs of toxicity 18, 19.
Even with excessive consumption of lutein, there are rarely reports of side effects. Regardless, more studies are needed to determine the risks of high-dose long-term lutein supplements.
However, the general consensus is that regular dietary lutein supplementation, along with other antioxidants, is beneficial for maintaining general eye health, including enhancing visual acuity and contrast sensitivity, while also reducing glare and discomfort.
References
- LH Li, J Chung-Yung Lee, HH Leung, WC Lam, Z Fu, A Cheuk Yin Lo. Lutein Supplementation for Eye Diseases. Nutrients. 2020; 12(6): 1721.
- EJ Johnson. Role of lutein and zeaxanthin in visual and cognitive function throughout the lifespan. Nutr Rev. 2014;72(9):605-612.
- RA Bone, JT Landrum, SL Tarsis. Preliminary identification of the human macular pigment. Vision Res. 1985;25(11):1531-1535.
- A Junghans, H Sies, W Stahl. Macular pigments lutein and zeaxanthin as blue light filters studied in liposomes. Arch. Biochem. Biophys. 2001; 391: 160–164.
- JT Landrum, RA Bone, NI Krinsky, ST Mayne, H Sies. Carotenoids in Health and Disease. Marcel Dekker: New York, NY, USA, 2004; pp. 445–472.
- B Kisic, D Miric, L Zoric. Free Radical Biology of Eye Diseases. In: Laher I. (eds) Systems Biology of Free Radicals and Antioxidants. Springer, Berlin, Heidelberg. 2014.
- SY Li, FK Fung, ZJ Fu, D Wong, HH Chan, AC Lo. Anti-inflammatory effects of lutein in retinal ischemic/hypoxic injury: in vivo and in vitro studies. Invest Ophthalmol Vis Sci. 2012;53(10):5976-5984.
- N.A. Antioxidant status and neovascular age-related macular degeneration. Eye Disease Case-Control Study Group . Arch Ophthalmol. 1993;111(1):104-109.
- MM Moschos, M Dettoraki, M Tsatsos, G Kitsos, C Kalogeropoulos. Effect of carotenoids dietary supplementation on macular function in diabetic patients. Eye Vis (Lond). 2017;4:23.
- M Sasaki, Y Ozawa, T Kurihara, et al. Neurodegenerative influence of oxidative stress in the retina of a murine model of diabetes. Diabetologia. 2010;53(5):971-979.
- M Muriach, F Bosch-Morell, G Alexander, et al. Lutein effect on retina and hippocampus of diabetic mice. Free Radic Biol Med. 2006;41(6):979-984.
- BJ Lyle, JA Mares-Perlman, BE Klein, R Klein, JL Greger. Antioxidant intake and risk of incident age-related nuclear cataracts in the Beaver Dam Eye Study. Am J Epidemiol. 1999;149(9):801-809.
- J Karppi, JA Laukkanen, S Kurl. Plasma lutein and zeaxanthin and the risk of age-related nuclear cataract among the elderly Finnish population. Br J Nutr. 2012;108(1):148-154.
- S Buscemi, D Corleo, P Di Pace, ML Petroni, A Satriano, G Marchesini. The Effect of Lutein on Eye and Extra-Eye Health. Nutrients. 2018;10(9):1321.
- NZ Unlu, T Bohn, SK Clinton, SJ Schwartz. Carotenoid absorption from salad and salsa by humans is enhanced by the addition of avocado or avocado oil. J Nutr. 2005;135(3):431-436.
- HI Chung, HM Rasmussen, EJ Johnson. Lutein bioavailability is higher from lutein-enriched eggs than from supplements and spinach in men. J Nutr. 2004;134(8):1887-1893.
- KM Ranard, S Jeon, ES Mohn, JC Griffiths, EJ Johnson, JW Erdman Jr. Dietary guidance for lutein: consideration for intake recommendations is scientifically supported. Eur J Nutr. 2017;56(Suppl 3):37-42.
- A Shao, JN Hathcock. Risk assessment for the carotenoids lutein and lycopene. Regul Toxicol Pharmacol. 2006;45(3):289-298.
- AJ Wenzel, JP Sheehan, C Gerweck, JM Stringham, K Fuld, J Curran-Celentano. Macular pigment optical density at four retinal loci during 120 days of lutein supplementation. Ophthalmic Physiol. Opt. 2007; 27: 329–335.