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Zeaxanthin
Zeaxanthin
Zeaxanthin
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Zeaxanthin
Structural formula of zeaxanthin
Space-filling model of the zeaxanthin molecule
Names
IUPAC name
(3R,3′R)-β,β-Carotene-3,3′-diol
Systematic IUPAC name
(1R,1′R)-4,4′-[(1E,3E,5E,7E,9E,11E,13E,15E,17E)-3,7,12,16-Tetramethyloctadeca-1,3,5,7,9,11,13,15,17-nonaene-1,18-diyl]bis(3,5,5-trimethylcyclohex-3-en-1-ol)
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.005.125 Edit this at Wikidata
E number E161h (colours)
UNII
  • InChI=1S/C40H56O2/c1-29(17-13-19-31(3)21-23-37-33(5)25-35(41)27-39(37,7)8)15-11-12-16-30(2)18-14-20-32(4)22-24-38-34(6)26-36(42)28-40(38,9)10/h11-24,35-36,41-42H,25-28H2,1-10H3/b12-11+,17-13+,18-14+,23-21+,24-22+,29-15+,30-16+,31-19+,32-20+/t35-,36-/m1/s1 checkY
    Key: JKQXZKUSFCKOGQ-QAYBQHTQSA-N checkY
  • InChI=1/C40H56O2/c1-29(17-13-19-31(3)21-23-37-33(5)25-35(41)27-39(37,7)8)15-11-12-16-30(2)18-14-20-32(4)22-24-38-34(6)26-36(42)28-40(38,9)10/h11-24,35-36,41-42H,25-28H2,1-10H3/b12-11+,17-13+,18-14+,23-21+,24-22+,29-15+,30-16+,31-19+,32-20+/t35-,36-/m1/s1
    Key: JKQXZKUSFCKOGQ-QAYBQHTQBL
  • CC1=C(C(C[C@@H](C1)O)(C)C)/C=C/C(=C/C=C/C(=C/C=C/C=C(/C=C/C=C(/C=C/C2=C(C[C@H](CC2(C)C)O)C)\C)\C)/C)/C
Properties
C40H56O2
Molar mass 568.88 g/mol
Appearance orange-red
Melting point 215.5 °C (419.9 °F; 488.6 K)
insol.
Related compounds
Related compounds
 lutein
xanthophyll
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Zeaxanthin is one of the most common carotenoids in nature, and is used in the xanthophyll cycle. Synthesized in plants and some micro-organisms, it is the pigment that gives paprika (made from bell peppers), corn, saffron, goji (wolfberries), and many other plants and microbes their characteristic color.[1][2]

The name (pronounced zee-uh-zan'-thin) is derived from Zea mays (common yellow maize corn, in which zeaxanthin provides the primary yellow pigment), plus xanthos, the Greek word for "yellow" (see xanthophyll).[citation needed]

Xanthophylls such as zeaxanthin are found in highest quantity in the leaves of most green plants, where they act to modulate light energy and perhaps serve as a non-photochemical quenching agent to deal with triplet chlorophyll (an excited form of chlorophyll) which is overproduced at high light levels during photosynthesis.[3] Zeaxanthin in guard cells acts as a blue light photoreceptor which mediates the stomatal opening.[4]

Animals derive zeaxanthin from a plant diet.[2] Zeaxanthin is one of the two primary xanthophyll carotenoids contained within the retina of the eye. Zeaxanthin supplements are typically taken on the supposition of supporting eye health. Although there are no reported side effects from taking zeaxanthin supplements, the actual health effects of zeaxanthin and lutein are not proven,[5][6][7] and, as of 2018, there is no regulatory approval in the European Union or the United States for health claims about products that contain zeaxanthin.

As a food additive, zeaxanthin is a food dye with E number E161h.[citation needed]

Isomers and macular uptake

[edit]

Lutein and zeaxanthin have identical chemical formulas and are isomers, but they are not stereoisomers. The only difference between them is in the location of the double bond in one of the end rings. This difference gives lutein three chiral centers whereas zeaxanthin has two. Because of symmetry, the (3R,3′S) and (3S,3′R) stereoisomers of zeaxanthin are identical. Therefore, zeaxanthin has only three stereoisomeric forms. The (3R,3′S) stereoisomer is called meso-zeaxanthin.[citation needed]

The principal natural form of zeaxanthin is (3R,3′R)-zeaxanthin. The macula mainly contains the (3R,3′R)- and meso-zeaxanthin forms, but it also contains much smaller amounts of the third (3S,3′S) form.[8] Evidence exists that a specific zeaxanthin-binding protein recruits circulating zeaxanthin and lutein for uptake within the macula.[9]

Due to the commercial value of carotenoids, their biosynthesis has been studied extensively in both natural products and non-natural (heterologous) systems such as the bacteria Escherichia coli and yeast Saccharomyces cerevisiae. Zeaxanthin biosynthesis proceeds from beta-carotene via the action of a single protein, known as a beta-carotene hydroxylase, that is able to add a hydroxyl group (-OH) to carbon 3 and 3′ of the beta-carotene molecule. Zeaxanthin biosynthesis therefore proceeds from beta-carotene to zeaxanthin (a di-hydroxylated product) via beta-cryptoxanthin (the mono hydroxylated intermediate). Although functionally identical, several distinct beta-carotene hydroxylase proteins are known.[citation needed]

Due to the nature of zeaxanthin, relative to astaxanthin (a carotenoid of significant commercial value) beta-carotene hydroxylase proteins have been studied extensively.[10]

Relationship with diseases of the eye

[edit]

Several observational studies have provided preliminary evidence for high dietary intake of foods including lutein and zeaxanthin with lower incidence of age-related macular degeneration (AMD), most notably the Age-Related Eye Disease Study (AREDS2).[11][12] Because foods high in one of these carotenoids tend to be high in the other, research does not separate effects of one from the other.[13][14]

  • Three subsequent meta-analyses of dietary lutein and zeaxanthin concluded that these carotenoids lower the risk of progression from early stage AMD to late stage AMD.[15][16][17]
  • A 2023 (updated) Cochrane review of 26 studies from several countries, however, concluded that dietary supplements containing zeaxanthin and lutein have little to no influence on the progression of AMD.[18] In general, there remains insufficient evidence to assess the effectiveness of dietary or supplemental zeaxanthin or lutein in treatment or prevention of early AMD.[2][13][18]

As for cataracts, two meta-analyses confirm a correlation between high serum concentrations of lutein and zeaxanthin and a decrease in the risk of nuclear cataract, but not cortical or subcapsular cataract. The reports did not separate a zeaxanthin effect from a lutein effect.[19][20] The AREDS2 trial enrolled subjects at risk for progression to advanced age-related macular degeneration. Overall, the group getting lutein (10 mg) and zeaxanthin (2 mg) did not reduce the need for cataract surgery.[21] Any benefit is more likely to be apparent in subpopulations of individuals exposed to high oxidative stress, such as heavy smokers, alcoholics or those with low dietary intake of carotenoid-rich foods.[22]

In 2005, the US Food and Drug Administration rejected a Qualified Health Claims application by Xangold, citing insufficient evidence supporting the use of a lutein- and zeaxanthin-containing supplement in prevention of AMD.[23] Dietary supplement companies in the U.S. are allowed to sell lutein and lutein plus zeaxanthin products using dietary supplement, such as "Helps maintain eye health", as long as the FDA disclaimer statement ("These statements have not been evaluated...") is on the label. In Europe, as recently as 2014, the European Food Safety Authority reviewed and rejected claims that lutein or lutein plus zeaxanthin improved vision.[24]

Natural occurrence

[edit]

Zeaxanthin is the pigment that gives paprika, corn, saffron, wolfberries (goji), and many other plants their characteristic colors of red, orange or yellow.[2][18] Spirulina is also a rich source and can serve as a dietary supplement.[25] Zeaxanthin breaks down to form picrocrocin and safranal, which are responsible for the taste and aroma of saffron.[26]

Dark green leaf vegetables, such as kale, spinach, turnip greens, collard greens, romaine lettuce, watercress, Swiss chard and mustard greens are rich in lutein[2][27] but contain little to no zeaxanthin, with the exception of scallions cooked in oil.[28] Orange bell peppers (but not green, red, or yellow) are rich in zeaxanthin.[28]

Lutein and zeaxanthin concentrations in fruits and vegetables (μg / 100 g)[28]
Food (100 g) Lutein trans (μg) Zeaxanthin trans (μg)
Spinach, cooked 12,640 0
Spinach, raw 6,603 0
Kale, cooked 8,884 0
Cilantro 7,703 0
Scallions, cooked in oil 2,488
Scallions, raw 782 0
Bell pepper, green 173 0
Bell pepper, orange 208 1,665
Bell pepper, red 0 22
Bell pepper, yellow 139 18
Cornmeal, yellow 1 531
Cornmeal, white 13 13
Corn, cooked from frozen 202 202
Tortilla, corn 276 255

Safety

[edit]

An acceptable daily intake level for zeaxanthin was proposed as 0.75 mg/kg of body weight/day, or 53 mg/day for a 70 kg adult.[29] In humans, an intake of 20 mg/day for up to six months had no adverse effects.[29] As of 2016, neither the U.S. Food and Drug Administration nor the European Food Safety Authority had set a Tolerable Upper Intake Level (UL) for lutein or zeaxanthin.[citation needed]

References

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Zeaxanthin

View on Grokipedia
from Grokipedia
Zeaxanthin is a xanthophyll carotenoid, specifically β,β-carotene-3,3′-diol, with the molecular formula C₄₀H₅₆O₂ and a molecular weight of 568.8 daltons, featuring 11 conjugated double bonds that contribute to its yellow-orange pigmentation and antioxidant properties. As a non-provitamin A carotenoid, it cannot be converted to vitamin A in humans and must be obtained through dietary sources, where it accumulates selectively in the macula lutea of the retina to filter harmful blue light and neutralize reactive oxygen species (ROS). The primary dietary sources of zeaxanthin include dark green leafy vegetables such as (up to 114.7 µg/g fresh weight of + zeaxanthin) and (59.3–79.0 µg/g of + zeaxanthin), as well as corn (10.3 µg/g zeaxanthin), orange bell peppers, yolks (approximately 213 µg zeaxanthin per yolk), and certain fruits like goji berries. Its is enhanced by the presence of dietary fats, methods like cooking or puréeing, and the food matrix, with typical daily intake of + zeaxanthin in Western diets ranging from 1–3 mg (zeaxanthin ~0.3 mg), though combined levels around 6 mg/day (including 2 mg zeaxanthin) are associated with reduced risk of age-related eye conditions. Humans absorb zeaxanthin primarily in the via passive diffusion, after which it is incorporated into lipoproteins for transport and deposition in tissues like the eyes, liver, and skin. Zeaxanthin exerts significant health benefits through its potent activity, quenching at a rate of 2.3 × 10⁸ M⁻¹s⁻¹—more effectively than its isomer —and protecting against in multiple organs. In ocular health, it forms part of the macular pigment, reducing the risk of age-related (AMD) by up to 82% in individuals with high retinal levels (of + zeaxanthin) and improving and contrast sensitivity, as demonstrated in clinical trials like AREDS2. As of 2025, recent studies continue to support these eye health benefits and suggest potential roles in immune enhancement against cancer and alleviation of dry eye symptoms. Beyond the eyes, zeaxanthin supports cardiovascular health by inhibiting (LDL) oxidation, aids liver protection against non-alcoholic (NAFLD) by mitigating ROS-induced inflammation, and shields skin from (UV)-induced damage. No adverse effects have been reported from dietary or supplemental intake up to 20 mg/day, underscoring its safety profile.

Chemistry

Molecular Structure and Properties

Zeaxanthin is a carotenoid characterized by the molecular formula C₄₀H₅₆O₂ and the systematic IUPAC name (3R,3'R)-β,β-carotene-3,3'-diol. Its structure consists of a linear polyene chain with 11 conjugated double bonds flanked by two β-ionone rings, each bearing a hydroxyl group at the 3 and 3' positions, respectively, which imparts its oxygenated nature as a . This configuration distinguishes it from non-hydroxylated like β-carotene, enhancing its polarity while maintaining lipophilicity. Zeaxanthin is a of , differing primarily in the ring double-bond positions. Physically, zeaxanthin manifests as an orange-red crystalline powder that is highly lipophilic, exhibiting good solubility in fats, oils, , and but negligible solubility in due to its non-polar backbone and limited hydrophilic hydroxyl groups. Its is approximately 215 °C, at which it decomposes without . In terms of , zeaxanthin displays characteristic UV-Vis absorption maxima at 450 nm and 478 nm in , corresponding to its extended that enables light absorption in the blue-violet range. In , zeaxanthin is biosynthesized within plastids through the pathway, starting from the acyclic precursor . undergoes stereospecific cyclization catalyzed by lycopene β-cyclase (LCYB) to form β-, which features two β-ionone rings. Subsequent at the 3 and 3' positions of β- is mediated by β- 3-hydroxylase (BCH), a non-heme diiron (also known as HYD in and ), often proceeding via the mono-hydroxylated intermediate β- to yield the final structure. This enzymatic pathway is tightly regulated and localized in chloroplasts and chromoplasts, contributing to zeaxanthin's role in pigment accumulation. Industrial production of zeaxanthin relies on , typically employing a C15 + C10 + C15 coupling strategy using β-ionone or as starting materials. β-Ionone, a key C13 building block derived from via with acetone followed by cyclization, is extended through Wittig olefination or Horner-Wadsworth-Emmons reactions to construct the central polyene chain, with subsequent introduction of hydroxyl groups and stereoselective adjustments to achieve the (3R,3'R) configuration. For structural identification, zeaxanthin exhibits a molecular ion peak at m/z 568 [M]⁺ in electron impact mass spectrometry, confirming its molecular weight, while ¹H NMR reveals characteristic signals including olefinic protons in the 6.0–6.7 ppm range for the conjugated double bonds, methyl singlets at 1.0–1.5 ppm, and hydroxyl protons around 4.0–5.0 ppm in CDCl₃.

Isomers and Synthesis

Zeaxanthin possesses two chiral centers at the C3 and C3' positions of its β-ionone rings, resulting in three stereoisomers: (3R,3'R)-zeaxanthin, which is the predominant all-trans form in ; meso-zeaxanthin ((3R,3'S)-zeaxanthin); and (3S,3'S)-zeaxanthin. The (3R,3'R) and (3S,3'S) forms are enantiomers exhibiting optical activity, whereas meso-zeaxanthin is meso due to its plane of symmetry and lacks . These isomers differ in key properties relevant to their biological roles. Meso-zeaxanthin demonstrates greater accumulation in the central macular region compared to (3R,3'R)-zeaxanthin, contributing to its prominence in ocular tissues. Additionally, meso-zeaxanthin exhibits distinct antioxidant capabilities, including superior quenching of relative to (3R,3'R)-zeaxanthin under certain conditions, though both provide effective protection against when interacting with S-transferase P1. Chemical synthesis of zeaxanthin primarily employs a double Wittig olefination as the key step, condensing a symmetrical C10 dialdehyde (such as pseudoionone-derived) with two equivalents of the C15 Wittig salt prepared from β-ionone, followed by hydrolysis and purification to yield the all-trans (3R,3'R) isomer with purity exceeding 98%. This route, developed through advancements in organophosphorus chemistry, enables scalable production of stereospecific zeaxanthin. For sustainable alternatives, microbial fermentation utilizes metabolically engineered organisms, including yeasts like Yarrowia lipolytica and algae such as Chlamydomonas reinhardtii, where pathway modifications—such as overexpression of β-carotene hydroxylase genes—achieve titers up to 81.5 mg/L and purities suitable for nutraceutical applications, reducing reliance on plant extraction. More recent engineering in other yeasts, such as Saccharomyces cerevisiae, has reported titers exceeding 800 mg/L in fed-batch processes as of 2023. Zeaxanthin was first isolated from corn in 1929 by Paul Karrer and colleagues, marking a milestone in chemistry. Synthetic production advanced significantly in the post-1950s period, coinciding with the broader application of Wittig reactions to complex polyene structures, enabling efficient and stereocontrol by the 1970s.

Biological Role

Occurrence in Nature

Zeaxanthin is a widely distributed in photosynthetic organisms, where it serves as an in , absorbing blue-green light (450–500 nm) to facilitate energy transfer to while contributing to photoprotection against excess light energy. In , it is particularly abundant in certain species and tissues, such as corn (Zea mays), where concentrations in sweet corn kernels can exceed 2 mg/100 g fresh weight in biofortified varieties, and orange bell peppers (Capsicum annuum), with levels ranging from 2.6 to 25 mg/100 g fresh weight depending on the cultivar. Goji berries (Lycium barbarum) are another notable source, containing up to 2 mg/g dry weight primarily as zeaxanthin dipalmitate, while marigold flowers (Tagetes erecta) exhibit exceptionally high levels, reaching 10–20 mg/g dry weight in petals of select cultivars. These concentrations highlight zeaxanthin's role in pigmentation and its accumulation in reproductive and protective plant structures. In animals, zeaxanthin is not synthesized de novo but accumulates through dietary uptake from sources, often depositing in tissues for coloration and structural purposes. It contributes to the vibrant hues in bird feathers, such as the pink pigmentation in ( spp.), where it is metabolized alongside other like from algal diets, and in canaries (Serinus canaria), where supplemental zeaxanthin enhances yellow-to-orange feather colors via direct deposition and metabolic conversion. Similarly, zeaxanthin is found in fish skin, particularly in species like (Oncorhynchus mykiss), aiding in pigmentation, and in egg yolks of , where concentrations of 6–10 μg/g arise from feed-derived uptake, imparting the characteristic yellow tint. This underscores zeaxanthin's ecological role in animal signaling and without endogenous production. Microorganisms also produce zeaxanthin, primarily for photoprotection in light-exposed environments. In , species like Chlorella zofingiensis accumulate zeaxanthin as part of the xanthophyll cycle to dissipate excess energy and prevent oxidative damage, though Haematococcus pluvialis is better known for , with zeaxanthin serving as a biosynthetic precursor. such as Flavobacterium spp. are prolific producers, yielding up to 190 mg/L in cultures, where zeaxanthin shields against UV radiation and supports stability. These microbial sources demonstrate zeaxanthin's conserved function across prokaryotes and simple eukaryotes in harsh, illuminated habitats. Biosynthetic pathways for zeaxanthin vary significantly across taxa, reflecting evolutionary adaptations. In and microorganisms, it is synthesized from through by β-carotene hydroxylase enzymes within the terpenoid pathway, enabling active production for photosynthetic needs. In contrast, animals lack these enzymes and rely solely on dietary absorption and selective deposition into tissues like feathers and , without the capacity for . This distinction highlights zeaxanthin's role as a dietary-dependent in higher organisms versus an endogenously produced protectant in photosynthetic lineages.

Function in Human Physiology

Zeaxanthin absorption occurs primarily in the , where it is incorporated into mixed micelles along with dietary fats after hydrolysis of its esters by pancreatic enzymes such as carboxyl ester lipase. These micelles facilitate passive or transporter-mediated uptake into enterocytes via scavenger receptors like SR-BI and CD36. Inside enterocytes, zeaxanthin is esterified or remains free and packaged into chylomicrons, which enter the and deliver it to the liver. From the liver, zeaxanthin is redistributed to peripheral tissues, including the , bound to lipoproteins such as LDL and HDL, with enhanced by concurrent dietary fat intake. Humans cannot synthesize zeaxanthin endogenously due to the absence of necessary biosynthetic enzymes, making dietary intake essential for its presence in the body. Zeaxanthin esters from food are efficiently hydrolyzed in the intestinal lumen prior to absorption, ensuring high bioaccessibility of the free form. Once absorbed, zeaxanthin exhibits a plasma of approximately 38 days, allowing for accumulation in target tissues over time. In the , zeaxanthin shows selective uptake and accumulation in the lutea, where it contributes significantly to macular pigment optical density (MPOD) alongside and the meso-zeaxanthin. This localization enables zeaxanthin to protect photoreceptors by absorbing high-energy blue light and quenching through non-photochemical , dissipating excess energy as harmless heat without generating further oxidants. Zeaxanthin exhibits synergistic interactions with in retinal tissues, where the two form stable complexes within cell , enhancing membrane rigidity and amplifying overall protection. This partnership optimizes the structural and functional integrity of photoreceptor membranes under .

Health Effects

Benefits for Eye Health

Zeaxanthin, often studied alongside , has been linked to a reduced risk of age-related () through its accumulation in the , where it contributes to the macular pigment optical density (MPOD). In the Age-Related Eye Disease Study 2 (AREDS2), supplementation with 10 mg and 2 mg zeaxanthin replaced beta-carotene in the original AREDS formula, resulting in an 18% lower risk of progression to late over 10 years compared to beta-carotene, particularly benefiting those at high risk without increasing incidence. Follow-up analyses through 2024 have confirmed these sustained MPOD benefits, with high-intake cohorts showing 10-20% risk reductions in progression. This protective effect is attributed to zeaxanthin's ability to filter harmful blue light, thereby mitigating photooxidative damage to cells. Higher dietary intake of zeaxanthin, exceeding 2 mg per day, is inversely associated with cataract risk, with meta-analyses indicating 15-25% reductions through its antioxidant properties. A 2023 meta-analysis of observational studies found that the highest versus lowest consumption of lutein and zeaxanthin was linked to a 19% decrease in age-related cataract incidence. Dose-response analyses further support this, showing approximately a 3% risk reduction in nuclear cataracts for every 300 μg daily increment in intake, equating to notable protection at levels above 2 mg. Zeaxanthin's antioxidant effects help preserve lens proteins by neutralizing free radicals and reducing oxidative stress, which otherwise leads to protein aggregation and lens opacification. Zeaxanthin also offers protection against other ocular conditions, including light-induced retinal damage. Experimental models confirm zeaxanthin's role in preventing light-induced death by elevating retinal levels and quenching . In pediatric populations, zeaxanthin supports visual development, with supplementation improving dynamic visual performance and macular levels in children. Randomized clinical trials have shown that lutein/zeaxanthin supplementation at 10-20 mg daily enhances visual function in 6-12 months. For instance, a double-blind study found that 10 mg plus 2 mg zeaxanthin over 6 months significantly improved contrast sensitivity and recovery time in healthy adults. Similar trials report gains in chromatic contrast and photostress recovery.

Potential Benefits Beyond Vision

Emerging indicates that zeaxanthin may offer protective effects in various non-ocular health domains, primarily through its and properties. These benefits are supported by clinical trials, epidemiological studies, and animal models, often examining zeaxanthin in combination with due to their similar and synergistic actions. In cognitive health, supplementation with zeaxanthin has shown promise for improving and processing speed in older adults. A randomized, double-blind, -controlled involving 90 adults aged 40–75 with self-reported mild cognitive complaints found that daily intake of 2 mg zeaxanthin combined with 10 mg for 6 months led to significant improvements in visual (p = 0.005) and visual learning (p = 0.001) compared to , with no notable effects on executive function or mood. These outcomes are attributed to zeaxanthin's ability to reduce brain , particularly in regions like the hippocampus, by neutralizing . Epidemiological evidence further links higher serum levels of zeaxanthin to better overall health and reduced cognitive decline in aging populations. For skin protection, zeaxanthin exhibits photoprotective effects against (UV) , potentially mitigating and . In a 2025 study using mice exposed to UVB , oral zeaxanthin from reduced skin damage by downregulating matrix metalloproteinases and preserving integrity by 35%, while activating the Nrf2 pathway to enhance defenses. Human studies support these findings; for instance, supplementation with 2 mg zeaxanthin and 10 mg daily increased the skin's minimal erythemal dose, delaying UV-induced redness and oxidative damage in clinical assessments. A 2024 review of oral photoprotection strategies highlighted that mixtures including zeaxanthin slowed UVB-induced development by 2–3 days and lowered expression of inflammatory enzymes like MMP-1 and MMP-9 in participants. Regarding cardiovascular health, zeaxanthin helps lower LDL oxidation, a key factor in atherosclerosis. A 2024 clinical trial demonstrated that supplementation with zeaxanthin, lutein, and meso-zeaxanthin significantly decreased serum oxidized LDL levels, alongside reductions in inflammatory markers like IL-1β and TNF-α, suggesting systemic anti-atherogenic effects. Epidemiological links also connect higher zeaxanthin intake to reduced cancer risk, particularly for breast and prostate cancers. In a 2025 population-based case-control study in Iran involving 600 breast cancer cases and 600 controls, higher dietary lutein/zeaxanthin intake (>2.51 mg/day) was associated with a 55% lower risk of breast cancer (adjusted OR = 0.45, 95% CI: 0.29–0.70, p < 0.001) compared to lower intake. For prostate cancer, an umbrella meta-analysis of 19 studies indicated that elevated carotenoid levels, including zeaxanthin, significantly decreased risk (pooled effect showing protective association). These benefits likely stem from zeaxanthin's inhibition of oxidative DNA damage and tumor promotion. Other potential roles include support for health and modulation of . Cross-sectional analyses from 2023 showed that higher blood zeaxanthin concentrations were positively associated with strength indices (e.g., cortical strength index, ratio) in older adults, suggesting a protective effect against . In animal models of , such as acetic acid-induced in rats, zeaxanthin reduced pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) and inhibited the pathway, alleviating colonic damage and . These findings highlight zeaxanthin's broader neuroprotective and anti-inflammatory potential in preclinical settings.

Sources and Intake

Dietary Sources

Zeaxanthin is primarily obtained from plant-based foods and animal products derived from animals fed carotenoid-rich diets, with corn, orange peppers, yolks, and berries among the richest sources. Corn contains approximately 0.2–1.0 mg of zeaxanthin per 100 g, depending on the variety and preparation, making it a staple contributor in many diets. Orange bell peppers provide 0.6–1.7 mg per 100 g fresh weight, with higher concentrations in certain cultivars. yolks offer 0.2–0.5 mg of zeaxanthin per yolk (typically from a 17 g yolk), enhanced by the hens' feed. Dried berries stand out with 25–152 mg per 100 g, primarily as zeaxanthin dipalmitate.
Food SourceZeaxanthin Content (mg/100 g or per serving)Notes
Corn (cooked, yellow sweet)0.2–1.0 mg/100 gVaries by variety; major source in processed corn products.
(raw)0.6–1.7 mg/100 gHighest in orange varieties; green peppers contain negligible amounts.
Egg yolk (cooked)0.2–0.5 mg per yolk (~1.2–2.9 mg/100 g yolk) improved due to content.
berries (dried)25–152 mg/100 gPredominantly zeaxanthin esters; common in .
Zeaxanthin often co-occurs with in foods, though the varies significantly. In leafy greens like , the zeaxanthin-to- is low (approximately 1:5 to 1:63), with containing over 15 mg of combined lutein and zeaxanthin per 100 g cooked but minimal isolated zeaxanthin. In contrast, corn exhibits a near 1:1 , while eggs show a slight lutein predominance (1.1:1). This co-occurrence influences overall intake, as most are lutein-dominant. Zeaxanthin is relatively heat-stable during cooking but sensitive to light exposure, which can degrade it over time. cooking methods, such as or , generally preserve content while potentially enhancing bioaccessibility; for instance, absorption from vegetable mixtures like increases from 20–40% in cooked forms compared to raw due to matrix disruption. or prolonged heating may reduce levels by 10–30%, though adding fats like oils improves uptake. Processing effects, such as drying goji berries or milling corn, concentrate zeaxanthin but can lead to losses if exposed to . Dietary patterns influence zeaxanthin intake, with Mediterranean and Asian diets providing higher amounts through abundant fruits, , and corn-based foods, often exceeding 1 mg daily. , average intake is 0.3–1 mg per day, reflecting lower consumption of high-zeaxanthin sources amid a typical diet yielding 1–3 mg of combined lutein and zeaxanthin.

Supplementation and Bioavailability

Zeaxanthin supplements are commonly available in free form or as diesters extracted from marigold flowers (Tagetes erecta), with commercial examples including OPTISHARP Natural Zeaxanthin and formulations paired with such as FloraGLO. Typical doses range from 10 to 20 mg per day for standalone zeaxanthin products, while in combined supplements like the AREDS2 formula, zeaxanthin is included at 2 mg alongside 10 mg to support macular health. Bioavailability of zeaxanthin is significantly enhanced when consumed with dietary fats or oils, which facilitate micellar incorporation in the intestine and can increase absorption by 2- to 3-fold compared to fat-free . The esterified form (diesters) and free form exhibit comparable overall absorption after enzymatic in the , where carboxyl ester and pancreatic enzymes cleave esters to release free zeaxanthin for uptake. Following oral supplementation, plasma zeaxanthin concentrations typically peak 4 to 6 hours post-dose, reflecting rapid intestinal absorption and distribution into lipoproteins. Clinical trials demonstrate that zeaxanthin supplementation elevates macular pigment optical density (MPOD) more rapidly than dietary sources alone, with recent 2024 systematic reviews confirming significant MPOD improvements from formulas including zeaxanthin over 3 to 6 months. For instance, high-dose regimens have shown approximately 20% MPOD enhancement within 3 months in adults with low baseline levels, outperforming groups. These supplements are generally cost-effective (around $0.10–$0.30 per daily dose) and widely accessible over-the-counter, making them practical for targeted use. Although zeaxanthin is not an , supplementation at 2 mg daily is recommended for populations with low dietary intake, such as the elderly, who often consume less than 1–2 mg from food sources and may benefit from enhanced .

Safety and Regulation

Toxicity and Side Effects

Zeaxanthin exhibits a low order of , with oral LD50 values exceeding 2000 mg/kg body weight in rats and up to 4000 mg/kg in rats and 8000 mg/kg in mice, based on regulatory studies in rodents. No cases of have been reported in humans at typical dietary or supplemental intake levels of up to 20 mg per day. Chronic exposure to zeaxanthin is generally well-tolerated, though rare instances of carotenodermia—a reversible yellowing of the skin—have been observed at high doses exceeding 30 mg per day. Assessments by the (EFSA) from 2012 onward indicate no evidence of or carcinogenicity associated with zeaxanthin intake. The (EFSA) has established an (ADI) for zeaxanthin of 0.75 mg/kg body weight per day (equivalent to approximately 53 mg/day for a 70 kg adult). In vulnerable populations, zeaxanthin consumed at levels found in food is considered safe during , though data on supplemental use remain limited. Caution is advised for smokers regarding potential interactions with beta-carotene, but EFSA evaluations suggest zeaxanthin itself is unlikely to elevate risk in this group. Recent reviews, including those from 2023 and 2024, affirm that zeaxanthin at recommended doses has no adverse impacts on liver or function, supporting its overall safety profile in long-term use. There is no established Recommended Dietary Allowance (RDA) for zeaxanthin, as it is not classified as an essential nutrient by major health authorities, but guidelines suggest intakes of 2-10 mg per day for supporting eye health, often in combination with lutein. The Age-Related Eye Disease Study 2 (AREDS2), conducted by the National Eye Institute, recommends 2 mg of zeaxanthin daily alongside 10 mg of lutein for individuals at risk of age-related macular degeneration (AMD), based on evidence that this combination reduces progression to advanced AMD by approximately 10-25% compared to beta-carotene. Indirect guidance from the World Health Organization (WHO) and Food and Agriculture Organization (FAO) emphasizes total carotenoid intake from fruits and vegetables, with provitamin A carotenoids like beta-carotene contributing to meeting vitamin A needs of 700–900 μg retinol activity equivalents (RAE) per day for adults, though non-provitamin A carotenoids such as zeaxanthin are encouraged through diverse diets without specific quantified targets. In the United States, zeaxanthin holds (GRAS) status from the (FDA) for use as a direct and in dietary supplements, with multiple GRAS notices affirming its at levels up to 300 micrograms per serving in foods like cereals, beverages, and dairy products. In the , zeaxanthin is approved as a under the designation E161h, typically permitted at levels in various categories for coloring purposes. It is also included in the Union Register of Feed Additives and authorized for use in animal feed, such as , at concentrations up to 20 mg/kg, as evaluated by the (EFSA). FDA regulations require appropriate disclosure of content on supplement labels to provide accurate information. Adequacy of zeaxanthin status is often monitored through serum levels, with concentrations above 0.1 μmol/L generally considered indicative of sufficient intake for eye health benefits, while levels below 0.07 μmol/L signal potential deficiency. Data from the National Health and Nutrition Examination Survey (NHANES) up to 2024 reveal that average daily intake of lutein plus zeaxanthin is approximately 1.58 mg among U.S. adults, with suboptimal serum levels observed in a significant portion—estimated at around 40%—particularly among older adults and those with low fruit and vegetable consumption, highlighting widespread dietary gaps. Emerging proposals in 2025 from organizations like the Alzheimer's Drug Discovery Foundation and ongoing clinical trials are advocating for the inclusion of zeaxanthin in cognitive health guidelines, building on evidence that 2-10 mg daily supplementation may support memory and neural function in aging populations, potentially expanding beyond ocular recommendations.

References

  1. https://pubchem.ncbi.nlm.nih.gov/compound/Zeaxanthin
  2. https://pmc.ncbi.nlm.nih.gov/articles/PMC6770730/
  3. https://lpi.oregonstate.edu/mic/dietary-factors/phytochemicals/carotenoids
  4. https://pmc.ncbi.nlm.nih.gov/articles/PMC3705341/
  5. https://ecancer.org/en/news/26970-plant-based-nutrient-improves-immune-cells-ability-to-fight-cancer
  6. https://www.aaojournal.org/article/S0161-6420%2824%2900425-1/fulltext
  7. http://www.thegoodscentscompany.com/data/rw1416271.html
  8. https://www.pnas.org/doi/10.1073/pnas.252500999
  9. https://www.sciencedirect.com/science/article/pii/S0254629920309212
  10. https://patents.google.com/patent/US8222458B2/en
  11. https://digitalcommons.fiu.edu/context/etd/article/3415/viewcontent/FI14060193reduced.pdf
  12. https://www.fda.gov/files/food/published/GRAS-Notice-000588----Zeaxanthin-from-Capsicum-annum-%2528paprika%2529.pdf
  13. https://patents.google.com/patent/JP5778676B2/en
  14. https://www.nature.com/articles/eye201398
  15. https://pmc.ncbi.nlm.nih.gov/articles/PMC8070478/
  16. https://www.mdpi.com/2076-3921/8/9/390
  17. https://www.fao.org/fileadmin/templates/agns/pdf/jecfa/cta/67/cta_zeaxanthin.pdf
  18. https://ift.onlinelibrary.wiley.com/doi/10.1111/j.1541-4337.2007.00028.x
  19. https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.699235/full
  20. https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-025-02676-9
  21. https://pubs.acs.org/doi/abs/10.1021/acs.jafc.5c00653
  22. https://www.polivkalab.cz/for_public/en_karotenoidy_od_a_do_z.html
  23. https://encyclopedia.pub/entry/16176
  24. https://www.sciencedirect.com/science/article/abs/pii/S0003986115000405
  25. https://www.mdpi.com/2504-3900/70/1/84
  26. https://www.sciencedirect.com/science/article/abs/pii/S0926669013000885
  27. https://patents.google.com/patent/EP1408737A2/en
  28. https://www.researchgate.net/publication/312056401_Flamingo_coloration_and_its_significance
  29. https://www.researchgate.net/publication/257273270_Lutein_zeaxanthin_meso-zeaxanthin_content_in_egg_yolk_and_their_absence_in_fish_and_seafood
  30. https://www.sciencedirect.com/science/article/abs/pii/S2211926421000850
  31. https://www.sciencedirect.com/science/article/pii/S1756464620300918
  32. https://pmc.ncbi.nlm.nih.gov/articles/PMC11016774/
  33. https://pmc.ncbi.nlm.nih.gov/articles/PMC12016392/
  34. https://www.chm.bris.ac.uk/motm/carotenoids/jcarotenoids.htm
  35. https://pmc.ncbi.nlm.nih.gov/articles/PMC5949277/
  36. https://pmc.ncbi.nlm.nih.gov/articles/PMC4698241/
  37. https://pmc.ncbi.nlm.nih.gov/articles/PMC7347445/
  38. https://pmc.ncbi.nlm.nih.gov/articles/PMC7570536/
  39. https://pmc.ncbi.nlm.nih.gov/articles/PMC4706936/
  40. https://pmc.ncbi.nlm.nih.gov/articles/PMC8874683/
  41. https://pubmed.ncbi.nlm.nih.gov/11481400/
  42. https://pmc.ncbi.nlm.nih.gov/articles/PMC8434335/
  43. https://jamanetwork.com/journals/jamaophthalmology/fullarticle/2792855
  44. https://content.govdelivery.com/accounts/USNIHODS/bulletins/3b620c2
  45. https://onlinelibrary.wiley.com/doi/10.1155/2015/687173
  46. https://www.mdpi.com/2072-6643/15/21/4585
  47. https://pubmed.ncbi.nlm.nih.gov/24150707/
  48. https://www.mdpi.com/2076-3921/9/11/1046
  49. https://iovs.arvojournals.org/article.aspx?articleid=2122959
  50. https://pmc.ncbi.nlm.nih.gov/articles/PMC10960892/
  51. https://iovs.arvojournals.org/article.aspx?articleid=2212732
  52. https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2022.843512/full
  53. https://pmc.ncbi.nlm.nih.gov/articles/PMC12189396/
  54. https://www.cureus.com/articles/158414-effects-of-plant-derived-dietary-supplements-on-skin-health-a-review
  55. https://onlinelibrary.wiley.com/doi/full/10.1111/phpp.12985
  56. https://pubmed.ncbi.nlm.nih.gov/38890092/
  57. https://pmc.ncbi.nlm.nih.gov/articles/PMC12487211/
  58. https://www.mdpi.com/2304-8158/13/9/1321
  59. https://bmcmusculoskeletdisord.biomedcentral.com/articles/10.1186/s12891-023-06370-5
  60. https://www.mdpi.com/2072-6643/15/4/1031
  61. https://pmc.ncbi.nlm.nih.gov/articles/PMC5331551/
  62. https://pmc.ncbi.nlm.nih.gov/articles/PMC11494239/
  63. https://www.kemin.com/na/en-us/markets/human-nutrition/products/carotenoids/floraglo-lutein
  64. https://www.nei.nih.gov/research/clinical-trials/age-related-eye-disease-studies-aredsareds2/about-areds-and-areds2
  65. https://www.brightfocus.org/resource/new-study-confirms-the-efficacy-of-areds2-eye-vitamin-supplement-for-slowing-age-related-macular-degeneration/
  66. https://www.sciencedirect.com/science/article/pii/S002364382400450X
  67. https://pmc.ncbi.nlm.nih.gov/articles/PMC9815984/
  68. https://www.liebertpub.com/doi/10.1089/jmf.2025.k.0060
  69. https://www.sciencedirect.com/science/article/pii/S2161831324000504
  70. https://jn.nutrition.org/article/S0022-3166%2824%2901129-5/fulltext
  71. https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2025.1522302/full
  72. https://www.healthline.com/nutrition/lutein-and-zeaxanthin
  73. https://www.mdpi.com/2072-6643/16/24/4366
  74. https://efsa.onlinelibrary.wiley.com/doi/abs/10.2903/j.efsa.2012.2891
  75. https://www.nei.nih.gov/research/clinical-trials/age-related-eye-disease-studies-aredsareds2/aredsareds2-frequently-asked-questions
  76. https://www.aao.org/eye-health/diseases/vitamins-amd
  77. https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/
  78. https://www.fda.gov/food/gras-notice-inventory/agency-response-letter-gras-notice-no-grn-000639
  79. https://efsa.onlinelibrary.wiley.com/doi/full/10.2903/j.efsa.2019.5698
  80. https://www.fda.gov/food/dietary-supplements-guidance-documents-regulatory-information/dietary-supplement-labeling-guide
  81. https://nutritionj.biomedcentral.com/articles/10.1186/s12937-025-01079-8
  82. https://www.alzdiscovery.org/uploads/cognitive_vitality_media/Lutein_and_zeaxanthin_%2528supplement%2529.pdf
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