When we wrote about eye health for World Optometry Day, we looked at how changes in blood sugar can temporarily affect the lens and blur your vision. For World Retina Week, we’re looking further back in the eye. The retina can be damaged long before you notice a change in your sight, particularly if you have diabetes. So which of the familiar advice about food and eyesight is useful, and which bits need a closer look?
Myth: Carrots will fix your eyesight.
Truth: Carrots contain beta-carotene, which your body can turn into vitamin A. Vitamin A is essential for normal vision, but extra carrots cannot fix a prescription or treat retinal disease. Leafy greens and eggs provide lutein and zeaxanthin, pigments found in the macula. They are good foods to include, but no single food can promise to protect your sight (1).
Myth: Screens are destroying your eyes.
Truth: Blue light attracts a lot of public concern, but there is no good evidence that normal screen use damages the retina. Screens can cause eye strain and dry eyes, especially with long periods of close-up use. A more serious threat to retinal health is poorly controlled diabetes: long-term high blood sugar can damage the retina and lead to diabetic retinopathy. Diabetic retinopathy is a leading cause of preventable vision loss in working-age adults worldwide (2).
Myth: Supplements are the shortcut to perfect vision.
Truth: AREDS2 formulas, containing lutein, zeaxanthin, zinc, and vitamins C and E, can help slow macular degeneration in people who already have it (3). But most people can get these nutrients from food: eggs, leafy greens, nuts, seeds, fatty fish. Talk to a doctor before starting any supplement, since food does not carry the same risk of overdosing.
Myth: All fat is bad for your eyes.
Truth: The retina actually needs certain fats. Omega‑3 fats from oily fish such as snoek, sardines, and mackerel are important components of retinal cells and may help support healthy blood vessels. Diets high in trans fats and ultra‑processed foods are linked to inflammation and a higher risk of diabetic eye disease (4). The issue is not fat itself, but the type of fat and the overall quality of the diet.
Myth: One “superfood” meal will save your eyes.
Truth: The retina responds to patterns, not single meals. Consistent intake of whole foods instead of refined carbs is what protects it over months and years. Drinking an occasional “eye health smoothie” won’t make a difference on its own; it’s the long‑term habits that count.
Myth: Sugar only wrecks your teeth.
Truth: Sugar does much more than cause cavities. Diets high in glycaemic load accelerate diabetic retinopathy by driving chronic hyperglycaemia and oxidative stress. Managing blood sugar is central to protecting the retina (5).
Myth: Vision problems are all in your genes.
Truth: Genetics play a role, but lifestyle factors such as smoking, poor diet, and metabolic health strongly influence risk and progression of retinal diseases like macular degeneration and cataracts (6).
Myth: If my vision is fine, my retina must be fine.
Truth: Diabetic retinopathy can develop without any noticeable change in vision. By the time sight becomes blurry, damage may already have occurred. If you have diabetes, managing your blood glucose and having regular dilated eye examinations are both important ways to protect your sight (2).
Retina Week is a good moment to separate what sounds true from what is actually backed by evidence. Your plate matters more than your supplement cabinet, and consistency matters more than any single food or habit.
References
- Office of Dietary Supplements. (2025, March 10). Vitamin A and carotenoids: Health professional fact sheet. National Institutes of Health. https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/
- Shukla UV, Tripathy K. Diabetic Retinopathy. [Updated 2023 Aug 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK560805/
- National Center for Complementary and Integrative Health. (2022, June). New analysis confirms benefit of supplements for slowing age‑related macular degeneration. National Institutes of Health. https://www.nccih.nih.gov/research/research-results/new-analysis-confirms-benefit-of-supplements-for-slowing-age-related-macular-degeneration
- Querques, G., Forte, R., & Souied, E. H. (2011). Retina and omega-3. Journal of nutrition and metabolism, 2011, 748361. https://doi.org/10.1155/2011/748361
- Ali, A., Deepshikha, & Nagar, Y. (2026). Dietary glycemic load and risk of diabetic retinopathy: A systematic review and meta‑analysis. International Journal of Research in Medical Sciences, 14(8), 2650. https://doi.org/10.18203/2320-6012.ijrms20262650
- Colijn, J. M., Meester-Smoor, M., Verzijden, T., de Breuk, A., Silva, R., Merle, B. M. J., Cougnard-Grégoire, A., Hoyng, C. B., Fauser, S., Coolen, A., Creuzot-Garcher, C., Hense, H. W., Ueffing, M., Delcourt, C., den Hollander, A. I., Klaver, C. C. W., & EYE-RISK Consortium (2021). Genetic Risk, Lifestyle, and Age-Related Macular Degeneration in Europe: The EYE-RISK Consortium. Ophthalmology, 128(7), 1039–1049. https://doi.org/10.1016/j.ophtha.2020.11.024