In the news: Lutein, Zeaxanthin: Emerging Research

Lutein, Zeaxanthin & Excess Screen Time

Consuming lutein and zeaxanthin has been hypothesized to play a beneficial role in people exposed to prolonged digital screen time. Macular pigment, composed of those two carotenoids plus the lutein by-product meso-zeaxanthin, is believed to provide retinal protection against photo-oxidative damage. Lutein has also been shown to possess anti-inflammatory properties.

Researchers recently evaluated the effect of supplemental lutein and zeaxanthin complex on macular pigment optical density (MPOD), contrast sensitivity, and quality of sleep, in healthy subjects (aged 18-55 years) with MPOD values below 0.8 who were exposed to an electronic device screen for a minimum of 8 hours daily(1).

Participants in this randomized, placebo-controlled, crossover study were divided into 3 groups: Group A received 10 mg lutein and 2 mg of zeaxanthin twice daily for the first 4 months, then continued the same regimen for 4 more months. Group B received 10 mg lutein and 2 mg zeaxanthin twice daily for the first 4 months, then switched to a placebo for the next four. Group C took a placebo for the first 4 months, then switched to the same dose of lutein and zeaxanthin for the subsequent 4 months. All groups underwent a 15-day washout after the first 4-month period.

After supplementation with lutein-zeaxanthin, the average MPOD (at 1ᴏ eccentricity) increased significantly in all groups. The average MPOD (right and left eyes) in group A was approximately two times higher than the placebo group.

In Group B MPOD values were consistent between 4 and 8 months, suggesting that the 4-month effect of supplemental lutein and zeaxanthin was retained.

In Group C, MPOD values between baseline and 4 months were not significantly different during the placebo period. MPOD levels then increased significantly between baseline and 8 months, reflecting the effect of supplementation.

Lutein and zeaxanthin supplementation also significantly improved contrast sensitivity, and the quality of sleep compared to placebo. Poor sleep quality is associated with excess screen time, possibly due to blue-light suppression of the sleep-regulating hormone melatonin.

Though preliminary, results of this study suggest that lutein / zeaxanthin may be promising for improving MPOD, contrast sensitivity and sleep quality in people exposed to prolonged screen time.

Zeaxanthin and Immunity

A team of University of Chicago researchers have long studied how nutrients influence the immune system. In a new experimental study, the group found that zeaxanthin may strengthen anti-tumor immunity(2,3).

In screening a large blood nutrient library, the team identified zeaxanthin as a nutrient that directly enhances the activity of CD8+ T cells. These cells rely on a molecular structure called the T-cell receptor (TCR) to recognize and destroy abnormal cells. The researchers found that zeaxanthin stabilizes and strengthens the formation of TCR complex on CD8+ cells for more robust T-cell activation.

In mouse models, dietary supplementation with zeaxanthin was observed to slow tumor growth. Importantly, when combined with immune checkpoint inhibitors (a state-of-the-art treatment), zeaxanthin significantly enhanced anti-tumor effects compared to immunotherapy alone.

Though this work is still at an early stage, it opens a new field of nutritional immunology and aims to find nutrients such as zeaxanthin that might render standard cancer therapies more effective.

References

1. Vadiraj G, et al. Beneficial effects of a lutein-zeaxanthin complex on macular pigment optical density levels of healthy individuals with prolonged screen time. Cureus (Springer Nature). 7(2):e79481, 2025.
2. Zhang F, et al. Zeaxanthin augments CD8+ effector T cell function and immunotherapy efficacy. Cell Reports Med. 102324 Epub Sept. 1, 2025
3. Abburi C. Univ Chicago Biologic Sci Dept. News. Sept. 1, 2025.