# Beneficial Effects of a Lutein-Zeaxanthin Complex on Macular Pigment Optical Density Levels of Healthy Individuals With Prolonged Screen Time

## TL;DR

Taking lutein and zeaxanthin supplements can boost eye health by increasing macular pigment in people who spend long hours on screens.

## Contribution

Demonstrates the long-term efficacy and safety of lutein-zeaxanthin supplementation in improving macular pigment and sleep quality in screen-heavy individuals.

## Key findings

- MPOD significantly increased after lutein-zeaxanthin supplementation compared to placebo.
- Improvements in contrast sensitivity and sleep quality were observed in supplemented groups.
- MPOD levels remained elevated even after discontinuation of supplementation.

## Abstract

Introduction

Macular pigment (MP), consisting of lutein (L) and zeaxanthin (Z), is believed to provide retinal protection against photo-oxidative damage. The objective of the study was to evaluate the effect of lutein and zeaxanthin complex 5:1 (extracted from marigold flowers) supplementation on macular pigment optical density (MPOD), contrast sensitivity, and quality of sleep in healthy subjects who exposed themselves to an electronic gadget screen for a minimum of 8 hours every day. This study also aimed to assess the long-term safety of the supplement by administering it for 8 months in one of the groups. The study also assessed the retention effects of lutein and zeaxanthin on MPOD after discontinuation of supplementation.

Methods

The study was registered with the Clinical Trial Registry of India (CTRI/2022/12/048392). Subjects were screened as per the defined inclusion and exclusion criteria. Subjects aged 18-55 years with a screen time of at least 8 hours daily and MPOD values below 0.8 were recruited. The study, conducted at Narayana Nethralaya Super Specialty Eye Hospital, Bangalore, spanned from December 2022 to May 2024. This was a randomized, placebo-controlled, crossover study. Of the 96 volunteers screened for this study, 71 were recruited, and 60 completed the study. Subjects were divided into 3 groups, viz. A, B, and C. Group A received lutein 10mg and zeaxanthin 2mg twice daily for the first four months, had a wash-off period of 15 days, and continued with the same supplementation for the remaining four months. Group B received lutein 10mg and zeaxanthin 2mg twice daily for the first four months, had a wash-off period of 15 days, and then switched over to a placebo for the next four months. Group C received a Placebo for the first 4 months, had a wash-off period of 15 days, and then switched over to lutein 10mg and zeaxanthin 2mg for the next four months.

All the subjects were given either, lutein and zeaxanthin complex-5:1 or placebo capsules as per the randomization chart prepared computationally. Subjects were analyzed for their MPOD values, contrast sensitivity scores, and quality of sleep. Intraocular pressure, retinal thickness, renal function tests, and liver function tests were conducted during visits to ensure clinical safety.

Results

After supplementation with the lutein-zeaxanthin complex-5:1, the average MPOD (at 1ᴏ eccentricity) increased significantly. At the first visit, the mean MPOD for Groups A, B, and C were 0.3, 0.22, and 0.29 (right eye) and 0.31, 0.27, and 0.27 (left eye), respectively. At the second visit, these values were 0.61, 0.66, and 0.21 (right eye) and 0.54, 0.53, and 0.2 (left eye). By the third visit, the mean MPOD values were 0.7, 0.65, and 0.38 (right eye) and 0.66, 0.53, and 0.36 (left eye). Supplementation significantly improved MPOD, contrast sensitivity, and the quality of sleep compared to placebo.

Conclusions

The supplementation with lutein and zeaxanthin resulted in higher MPOD values as compared to that of the placebo. This intervention also led to improvement in contrast sensitivity and quality of sleep. Lutein and zeaxanthin complex-5:1 may be a promising remedial measure for increasing the MPOD of people exposed to prolonged screen time.