Effect of a Nutraceutical-Oriented Dietary Intervention on Serum Carotenoids and Antioxidant Vitamin Concentrations in Patients with Neovascular Age-Related Macular Degeneration

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Background: Age-related macular degeneration (AMD) is one of the most common causes of irreversible impairment of central vision in the elderly population. Although anti-VEGF therapy remains the standard treatment for neovascular AMD, nutritional factors may influence disease progression and retinal health. The aim of this prospective controlled study was to evaluate the effects of an individualized dietary intervention with nutraceutical characteristics on serum concentrations of lutein, zeaxanthin, lycopene, vitamin A, and vitamin E in patients with neovascular AMD receiving anti-VEGF therapy. Methods: This prospective controlled study included 43 patients with neovascular AMD who completed a six-month follow-up period. Participants were allocated to either a control group receiving anti-VEGF therapy alone or an intervention group receiving anti-VEGF therapy combined with an individualized dietary plan. The dietary intervention emphasized foods naturally rich in carotenoids, antioxidant vitamins, trace elements, dietary fiber, and omega-3 fatty acids. Serum concentrations of lutein + zeaxanthin, lycopene, vitamin A, and vitamin E were determined using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) at baseline and after six months. Results: Serum lutein + zeaxanthin concentrations increased significantly within both groups (control 0.31 ± 0.61 to 0.49 ± 0.69 mg/L; intervention 0.51 ± 0.54 to 0.87 ± 0.89 mg/L). The increase was numerically larger in the intervention group, but the between-group difference was not statistically significant after adjustment for baseline concentrations (ANCOVA, p = 0.30). Lycopene increased significantly within the intervention group only (0.20 ± 0.15 to 0.43 ± 0.30 μmol/L); the between-group difference was not significant after baseline adjustment (p = 0.24). Vitamin A increased significantly within both groups and vitamin E within the intervention group only; however, no between-group difference remained significant after baseline adjustment (vitamin A p ≈ 1.00, vitamin E p = 0.96). The greatest increase in lutein + zeaxanthin concentrations was observed among participants with improved retinal status. These descriptive findings should be interpreted cautiously because subgroup analyses were not powered. Correlation analyses performed after six months demonstrated positive associations between serum lutein + zeaxanthin, lycopene, and vitamin A concentrations. Conclusions: An individualized dietary intervention rich in naturally occurring bioactive compounds was associated with within-group improvements in serum carotenoid and antioxidant vitamin status. After adjustment for baseline values, between-group differences did not reach statistical significance, consistent with the exploratory, non-powered pilot design. These preliminary findings, including the observed effect sizes, are intended to inform the design of an adequately powered future study rather than to establish a between-group benefit of dietary management. Particularly pronounced changes were observed for lutein + zeaxanthin and lycopene concentrations. These findings support the potential role of dietary management as an adjunct to anti-VEGF therapy. However, given the nature of the study and the relatively small sample size, larger multicenter studies are needed to confirm these observations.