A growing body of research suggests that higher dietary intake of the carotenoids lutein and zeaxanthin is linked with a lower risk of age-related macular degeneration (AMD). A large prospective cohort study published in JAMA Ophthalmology (2015 Dec;133(12):1415–1424. doi:10.1001/jamaophthalmol.2015.3590) further examined this relationship.
Cohort studies are observational in nature, meaning researchers track outcomes over time without introducing an intervention. In this study, investigators analyzed data from two long-running cohorts: the Nurses’ Health Study and the Health Professionals Follow-up Study. The analysis included 63,443 women and 38,603 men who were followed from 1984 through 2010. All participants were age 50 or older and were free of macular degeneration, diabetes, cancer, and cardiovascular disease at baseline.
Dietary intake was assessed using validated food-frequency questionnaires administered at the start of the study and repeated throughout the follow-up period. During the study, 2,479 cases of AMD were identified, including 1,361 intermediate cases and 1,118 advanced cases.
When researchers compared participants in the highest quintile of carotenoid intake with those in the lowest quintile, they found that the risk of developing advanced AMD was approximately 40% lower among those consuming the greatest amounts of carotenoids.
While observational data cannot establish cause and effect, these findings are consistent with the idea that long-term intake of lutein- and zeaxanthin-rich foods may support retinal health and are associated with a lower risk of advanced macular degeneration.
