The Effect of Lutein/Zeaxanthin Intake on Human Macular Pigment Optical Density: A Systematic Review and Meta-Analysis

Abstract

Lutein, zeaxanthin, and meso-zeaxanthin are the only carotenoids found in the human macula and may have a role in visual function. These carotenoids are reported to protect the retina, and thus vision, as antioxidants and by acting as a blue light filter. Our objective was to determine a minimum concentration of lutein/zeaxanthin intake that is associated with a statistically significant and/or clinically important change in macular pigment optical density (MPOD) among adults with healthy eyes. We searched Ovid MEDLINE, CENTRAL, and the Commonwealth of Agriculture Bureau for English-language studies through to July 2020. Two reviewers screened results to identify studies that evaluated supplements or dietary sources of lutein/zeaxanthin on MPOD among adults with healthy eyes. One reviewer extracted data and assessed strength of evidence, which was confirmed by a second reviewer. Two independent reviewers assessed the risk of bias. Meta-analyses were stratified by total lutein/zeaxanthin dose. We included 46 studies (N = 3189 participants; mean age = 43 y; 42% male). There was no statistically significant change in MPOD among studies evaluating <5 mg/d of total lutein/zeaxanthin intake which primarily assessed dietary interventions for 3–6 mo (pooled mean difference, 0.02; 95% CI: –0.01 to 0.05). The pooled mean increase in MPOD was 0.04 units (95% CI: 0.02 to 0.07) among studies evaluating 5 to <20 mg/d of lutein/zeaxanthin and was 0.11 units (95% CI: 0.06 to 0.16) among studies evaluating ≥20 mg/d of lutein/zeaxanthin for 3–12 mo. MPOD increased with lutein/zeaxanthin intake, particularly at higher doses, among adults with healthy eyes. The effects of lutein/zeaxanthin intake at doses <5 mg/d or from dietary sources is less clear. Increased lutein/zeaxanthin intake can help with maintaining ocular health. Future research is needed to determine the minimum dose and duration of lutein/zeaxanthin intake that is associated with a clinically important change in MPOD or visual function.

Is Melatonin the “Next Vitamin D”?: A Review of Emerging Science, Clinical Uses, Safety, and Dietary Supplements

“…One of the interesting benefits of phytomelatonin over an isolated, synthesized chemical compound of melatonin is the complex, diverse composition of phytochemicals in the plant matrix concentrate. For example, it contains small amounts of the xanthophyll carotenoids, lutein, and zeaxanthin, which are known to concentrate in the back of the eye, specifically in the macula and fovea [ 268 ]. Research suggests that these plant compounds may help protect the eyes by absorbing harmful blue light [ 268 , 269 ].…”

“…For example, it contains small amounts of the xanthophyll carotenoids, lutein, and zeaxanthin, which are known to concentrate in the back of the eye, specifically in the macula and fovea [ 268 ]. Research suggests that these plant compounds may help protect the eyes by absorbing harmful blue light [ 268 , 269 ]. Therefore, not only does phytomelatonin supply the bio-identical melatonin to help with circadian rhythm imbalance at night, but it also adds to the photoprotective compounds for the eye to shield against blue light, making for a complete multi-functional approach.…”

Assessment of Maternal Macular Pigment Optical Density (MPOD) as a Potential Marker for Dietary Carotenoid Intake during Lactation in Humans

“…Clinical documentation of MPOD as a quantitative, non-invasive marker for maternal dietary carotenoids and levels in breastmilk could help establish recommendations for carotenoids, which are important for health and neurodevelopmental outcomes in infants [ 4 , 6 , 10 , 26 , 27 , 28 , 29 ]. Significant associations between MPOD and carotenoid intake, especially lutein and zeaxanthin, have been previously found in general adult populations [ 16 , 22 , 30 , 31 , 32 , 33 , 34 ]. Most of these studies have not investigated the association of MPOD with other dietary carotenoids such as α-carotene, β-carotene, or lycopene.…”

“…While meso-zeaxanthin is believed to be generated enzymatically from lutein in the retina, lutein and zeaxanthin cannot be synthesized by humans and therefore must be obtained from the diet [ 15 , 16 , 17 ]. For this reason, MPOD has been used to assess the status of carotenoids, such as lutein and zeaxanthin, in the general population [ 18 , 19 , 20 , 21 , 22 ]. Similar to FFQs, MPOD can be measured non-invasively; however, the measurement takes less than 5 minutes and generates a single objective value.…”

Profiling of Nutritionally Vital Bioactive Compounds in Emerging Green Leafy Vegetables: A Comparative Study

“…In addition to the (all- E )-β-carotene, significantly high contents of (all- E )-lutein (204.6 μg/g FW) and (all- E )-zeaxanthin (84.2 μg/g FW) were recorded in moringa, compared to other studied GLVs. Lutein and zeaxanthin are macular pigments acting as blue light filters protecting the retina and, therefore, vision [ 49 ]. Studies have shown that increased lutein and zeaxanthin intake can help maintain ocular health [ 49 ].…”