Associations Between Nutritional Factors, Obesity and Ocular Diseases: A Narrative Literature Review

Background: Nutritional imbalances significantly affect ocular physiology, contributing to dry eye disease, cataracts, age-related macular degeneration (AMD), and optic neuropathies. This review summarizes recent evidence on how micronutrient deficiencies and obesity influence eye health. Methods: A narrative search was performed in PubMed, Scopus, and ScienceDirect (last 10 years). Human studies evaluating associations between micronutrients, dietary patterns, obesity, and ocular diseases were included. Out of 843 records, 50 studies met the eligibility criteria. Results: Deficiencies in vitamins A, D, E, C, and B-complex were consistently linked to ocular surface inflammation, retinal oxidative stress, cataracts, AMD, and nutritional optic neuropathies. Altered levels of zinc, copper, selenium, and magnesium were associated with impaired photoreceptor function, glaucoma risk, and retinal degeneration. Obesity emerged as an independent risk factor for AMD, diabetic retinopathy, and glaucoma through mechanisms involving oxidative stress and vascular dysfunction. Evidence from AREDS/AREDS2 supports targeted antioxidant supplementation in intermediate AMD. Conclusions: Adequate nutritional status and metabolic balance play a critical role in preserving ocular health. Early detection and correction of deficiencies may prevent or slow the progression of several eye diseases. Further high-quality trials are needed to define optimal nutritional recommendations.