Roles of Omega-3 Fatty Acids in Eye Health and Disease: A Review

Aims and Study Design: A literature review of the roles of omega-3 fatty acids (FA) and particularly EPA and DHA, in eye health, and, as disease-preventive and curative agents for various ocular ailments was undertaken.

Place and Duration of Study: It was done between December 2021 and May 2024.

at the Department of Food Science and Nutrition, Karatina University, Kenya.

Results: Omega-3 FA are needed for brain and vision development in infants and children, protecting the eye from degenerative damage and conferring anti-inflammatory benefits. They seem to prevent and slow macular degeneration, dry eye disease, and lower the risk of early age-related macular degeneration, glaucoma and retinopathy, thus lowering the risk of early vision loss. Fatty fish from the wild, krill, seaweed and sea algae are rich sources of the ω-3 FA, EPA and DHA, while walnuts, flaxseeds and flaxseed oil, chia seeds, canola and soybean oils, tofu and meat from grass-fed ruminants, are good sources of the nutrients, but as ALA. Commercially-prepared fried fish from restaurants and fast-food establishments, are relatively lower in the omega-3s, but high in trans-fatty acids due to high temperature thermal processing. Boiling in water, broiling or grilling for short periods are recommended for preparing fish for consumption and omega-3 FA retention. Dietary omega-3 FA are more efficacious than omega-3 FA from supplements, probably due to their synergistic interaction with lutein, beta-carotene, Vitamins A, C and E and Zinc.

Conclusion: It seems prudent to incorporate Vitamin A, C, E and Zinc during omega-3 FA supplement manufacture to boost their efficacy. Although health authorities recommend 1-2 meals of fatty fish edible portion/week and a daily intake of 0.5-1 g/day or more of the ω-3 FA for cardiovascular health, no definitive amounts are recommended for eye health and curing the various ocular diseases at this point in time. It is, however, increasingly being recommended that amounts of more than 1 g/day and up to 2 g/day are safe and more beneficial based on age, gender and health condition. The omega-3 index is a useful tool for maintaining the blood status of the omega-3 FA. Although ω-3 FA play important roles in eye health and the prevention of ocular dystrophies, the cardioprotective role of omega-6 FA, especially LA, against coronary heart disease cannot be discounted, such that drastic dietary or reduction of ω-6 FA when taken as supplements may be ill-advised at present, while balancing their ratio with that of the omega-3 FA seems to be appropriate health-wise.