LUTEIN AND ZEAXANTHIN IN THE PREVENTION AND TREATMENT OF AGE-RELATED EYE DISEASES: A REVIEW OF EFFICACY AND BIOAVAILABILITY STUDIES WITH A FOCUS ON OCULAR AND COGNITIVE HEALTH

Aim: This review analyses the role of lutein and zeaxanthin in preventing and treating age-related eye diseases, including age-related macular degeneration (AMD), cataracts, and glaucoma. Furthermore, it explores their critical applications in pediatric populations, pregnant women, and the broader socio-economic implications of visual impairment in the digital age. Materials and Methods: The review included scientific articles published from 2000 to 2025, sourced in English from PubMed and Scopus, using keywords such as lutein, zeaxanthin, AMD, cataract, glaucoma, retina, microbiome, and supplementation. The selection followed PRISMA protocols and AMSTAR 2 guidelines, incorporating clinical trials (RCTs), preclinical studies, and systematic reviews. Results: Lutein and zeaxanthin accumulate in the macula, neutralizing reactive oxygen species via the Nrf2 pathway and shielding against UV and digital blue light. Supplementation reduces the risk of AMD progression by 18–26%, cortical cataracts by 20–25%, and glaucoma by 15–20%. Advanced delivery methods, such as PLGA and lipid-based nanoparticles, increase carotenoid bioavailability by up to 40%. In preterm infants, supplementation reduces the risk of retinopathy by 50%. In children, it protects against screen-related photic damage, while in older adults, it boosts cognitive function by up to 12%. Conclusions: Lutein and zeaxanthin play a highly significant role in preventing age-related eye diseases and mitigating digital eye strain. Beyond individual clinical benefits, evidence-based, population-wide supplementation programs—enhanced by novel nanoparticle delivery systems and gut-microbiome modulation—can yield substantial socio-economic benefits by reducing the global burden of visual impairment. Future research must focus on large-scale RCTs to standardize dosing regimens.