Nutrition for Eye Health

The best nutrition for eye health is a diet rich in antioxidants, carotenoids (especially lutein and zeaxanthin), omega-3 fatty acids, vitamins (A, C, E, B6, folate, niacin), and minerals (zinc, copper, magnesium). High intake of green leafy vegetables (such as spinach, Swiss chard, and kale), colorful fruits and vegetables, cold-water fish (for omega-3s), nuts, and whole grains is associated with reduced risk and slower progression of common eye diseases including age-related macular degeneration (AMD), diabetic retinopathy, cataracts, and glaucoma.

Specifically, regular consumption of green leafy vegetables (≥2.7 servings/week), fish (≥2 servings/week), and foods high in lutein/zeaxanthin (≥2 mg/day) and omega-3 fatty acids (≥0.7 g/week) is linked to lower rates of AMD progression. Plant forward diets rich in antioxidants are associated with decreased risk of diabetic retinopathy, cataracts, glaucoma, and macular degeneration. Plant-forward and Mediterranean dietary patterns, which emphasize these foods and minimize processed foods and animal fats, have consistently shown to be protective.

In 2001, the results of the landmark 5-year Age-Related Eye Disease Study (AREDS) sponsored by the National Eye Institute were published. The research found that a daily antioxidant supplement containing beta-carotene, vitamin C, vitamin E, zinc, and copper reduced the risk of progressive AMD by 25% among those with early and intermediate macular degeneration. Furthermore, visual acuity loss was reduced by 19% in individuals at high-risk for AMD.

AREDS2 was a 5-year follow-up study published in 2013 to assess the effects of lutein and zeaxanthin (without beta-carotene) on the prevention of AMD and other age-related eye diseases. Research reported a 10-25% reduced risk of AMD progression though no benefit was observed for cataract risk or progression. While there is no universally established dosage for all individuals, the AREDS2 trial used: lutein 10 mg, zeaxanthin 2 mg, vitamin C 500 mg, vitamin E 400 IU, zinc 80 mg, and copper 2 mg daily for those at high risk of AMD progression.

Supplementation with AREDS2 formula nutrients is recommended for patients at high risk of advanced AMD, as supported by large clinical trials. However, for the general population, prioritizing dietary sources is preferred unless deficiencies are present.

Key Nutrients & Compounds for Eye Health

Lutein & Zeaxanthin

Lutein and zeaxanthin are xanthophyll carotenoids that accumulate in the macula, where they filter blue light and act as antioxidants. Higher dietary intake of these carotenoids, primarily from green leafy vegetables and eggs, is consistently associated with lower risk and slower progression of AMD and cataract. Oxidation of the lens is a major cause of cataracts, which cloud the lens. As antioxidant nutrients neutralize free radicals, unstable molecules, associated with oxidative stress and retinal damage, lutein and zeaxanthin likely play a role in cataract prevention. While research is stronger related to AMD, research does suggest that higher dietary intakes of lutein and zeaxanthin and vitamin E is associated with a decreased risk of cataract formation. In a study published in the journal Optometry, participants with early AMD who consumed 8 mg per day of dietary zeaxanthin for one year improved their night driving and their visual acuity improved an average of 1.5 lines on an eye chart.

The highest dietary sources include dark green leafy vegetables, particularly kale, spinach, Swiss chard, mustard greens, turnip greens, collard greens, and garden cress. In much smaller amounts, lutein and zeaxanthin are also found in other colorful fruits and vegetables like broccoli, corn, peas, persimmons and tangerines. Note that consuming ½ cup cooked kale, spinach, or Swiss chard approximately provides the amount of lutein and zeaxanthin used in the AREDS2 trial.

Vitamin C
Scientific evidence suggests vitamin C lowers the risk of developing cataracts and when taken in combination with other essential nutrients, it can slow the progression of AMD and visual acuity loss. Vitamin C supports the health of ocular blood vessels. A study demonstrated that women using vitamin C for 10 years or more experienced a 64 percent reduction in the risk of developing nuclear cataracts.

Dietary sources include bell peppers, kiwi, strawberries, papaya, tomatoes, & citrus fruits.

Vitamin E
Vitamin E protects cells in the eyes from unstable molecules called free radicals, which break down healthy tissue. Studies indicate that vitamin E reduces the progression of AMD and cataract formation.

Good food sources of Vitamin E include avocado, olive oil, and sweet potatoes.

Omega-3 fatty acids
Omega-3 fatty acids, specifically, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are important for proper visual development and retinal function. DHA is found in the highest concentration in the retina, suggesting it has an important functional role while EPA is used in DHA biosynthesis. Studies in pre-term and full-term infants suggest that consuming adequate omega-3 fatty acids in the diet is essential for optimal visual development. Additionally, these fatty acids are important for retinal function, help reduce inflammation, enhance tear production, and support the eye’s oily outer layer. Omega-3 fatty acids, especially EPA and DHA from fish, are linked to reduced progression of AMD and may benefit dry eye syndrome. Note that alpha linolenic acid (ALA) may have beneficial effects on eye health, likely due to its anti-inflammatory and antioxidant properties, but clinical evidence for its efficacy in preventing or treating specific ocular diseases is limited and inconsistent.

The best dietary sources of EPA and DHA are cold-water fish, including salmon, sardines, trout, black cod, mackerel, and herring. For individuals who choose not to consume fish, vegetarian DHA is commercially manufactured from microalgae in smaller amounts. ALA dietary sources include sacha inchi seeds, flax seed, chia seeds, basil seeds, walnuts, and hemp hearts.

Zinc
Zinc plays a vital role in eye health, particularly in retinal physiology and the pathogenesis and progression of AMD. Zinc helps to bring vitamin A from the liver to the retina in order to produce melanin, a protective pigment in the eyes. Impaired vision, such as poor night vision and cloudy cataracts, has been linked to zinc deficiency. Clinical trial data, most notably from AREDS, demonstrated that 40-80 mg zinc supplementation, especially when combined with antioxidants, modestly reduces the risk of progression to advanced AMD and significant visual acuity loss in patients with intermediate AMD or advanced AMD in one eye. The recommended AREDS formulation includes 80 mg of zinc oxide daily, but this dosage should be considered in the context of potential adverse effects such as copper deficiency and gastrointestinal symptoms. Higher levels of zinc may interfere with copper absorption, which is why the AREDS study also included a copper supplement. Additionally, note that zinc oxide is poorly bioavailable and more likely to cause gastrointestinal distress. The absorption rate of zinc oxide from the gastrointestinal tract is generally low, ranging from 5-10%. I would suggest a zinc glycinate that is more highly bioavailable and much better tolerated and a fraction of the dose needed.

The richest dietary source of zinc are oysters; other protein-rich foods also provide zinc, including fish, poultry, tofu, nuts and seeds.

Magnesium
Magnesium plays a critical role in eye health by maintaining the structural and functional integrity of ocular tissues such as the cornea, lens, and retina. Magnesium deficiency disrupts ATPase activity, leading to ionic imbalances (increased intracellular calcium and sodium, decreased potassium), which can contribute to the development of cataract and other ophthalmic diseases. Additionally, lower magnesium status is associated with increased risk of diabetic retinopathy and diabetic macular edema, with higher magnesium intake or supplementation showing a protective effect.

The highest dietary sources of magnesium include spinach, chard, pumpkin seeds, chia seeds, and hemp hearts.

Vitamin A
Vitamin A is essential for good vision, especially in low light, by helping produce rhodopsin. Additionally, vitamin A is crucial for the ocular surface epithelium, and deficiencies are linked to dry eye syndrome. Vitamin A plays a pivotal role in mucin production, which imparts a gel-like consistency to the tear film, essential for its stabilizing function.

Dietary sources of vitamin A include liver, eggs, and animal protein. Rich sources of beta-carotene, the precursor to vitamin A, include carrots, sweet potatoes, and pumpkins.

B vitamins
Various B vitamins, including B6, folate, and niacin are protective against the development of cataracts. Folate has been shown to play an important role in eye development; there are folate transport proteins in certain eye tissues. In this trial, higher intakes of vitamin B6 and niacin in the top quartile were significantly associated with a reduced likelihood of cataract occurrence. Among other nutrients, in this study, vitamin B6 and folate were associated with a significant decreased risk of late AMD.

Dietary sources:

Vitamin B6 - turkey, salmon, chicken, tofu, sunflower seeds, pistachios, chickpeas
Folate – edamame, kidney beans, black beans, liver, lentils, spinach, asparagus, broccoli, avocado
Niacin - fish, chicken, hemp hearts, chia seeds, sunflower seeds, peanuts

Saffron
Saffron and its active compounds, crocin and crocetin, have shown promising results in improving visual function. Saffron acts as an antioxidant by depleting free radicals in oxidative stress. Several clinical studies have found that daily supplementation with 20–50 mg of saffron or 5–15 mg of crocin for 3–12 months significantly improved best-corrected visual acuity, contrast sensitivity, and retinal function, with benefits observed in both dry and wet forms of AMD. In a randomized, double-blind, placebo-controlled study on diabetic maculopathy, subjects who received crocin 15 mg/day oral supplementation significantly improved best-corrected visual acuity and reduced central macular thickness, suggesting that crocin may have anti-inflammatory and neuroprotective effects in the treatment of refractory diabetic macular edema. Saffron may delay the progression of AMD through anti-angiogenic, neuroprotective, and antioxidant mechanisms.

Bilberry
Bilberries are a rich source of protective anthocyanins; the extracts from the fruits and leaves have been used for vision-related ailments for many years. Bilberry supplementation may help prevent lens and retina impairments. Furthermore, bilberry extract may offer protective effects against oxidative retinal damage and could serve as a complementary approach in managing early diabetic retinopathy. And bilberry extract (600mg daily for 3 months) has been shown to alleviate the symptoms of dry eye syndrome.

Maqui Berry
If you struggle with dry eyes, I would highly consider maqui berry extract. Maqui berry, native to the Patagonia region of Chile, is rich in anthocyanins, and has been used as a traditional medicine to treat inflammation. Consumption of 60 mg of a maqui berry extract taken once daily for 4 weeks reduced eye dryness and appeared to alleviate eye fatigue. In a separate trial, 60mg maqui berry extract was again shown to improve dry eye syndrome; it also reduced ocular surface inflammation based on tear biomarker profiling.

Is there a connection between GLP-1s and vision?
While currently in the earlier stages of research, glucagon-like peptide-1 receptor agonists (GLP-1 RAs) can influence vision primarily by increasing the risk of certain optic nerve and retinal complications, especially in those who have diabetes. Multiple large observational studies and clinical trials have reported an association between GLP-1 RAs—particularly semaglutide and tirzepatide—and an increased risk of nonarteritic anterior ischemic optic neuropathy (NAION), diabetic retinopathy (DR) progression, and other retinal events such as macular edema, retinal detachment, and vitreous hemorrhage. While the absolute risk remains low, the relative risk is elevated compared to other antidiabetic agents, especially in those with preexisting retinopathy or rapid glycemic improvement. The SUSTAIN 6 trial and subsequent population-based studies have confirmed these findings, with the risk of vision-threatening events such as vitreous hemorrhage and blindness being higher in the GLP-1 RA group. Hence, GLP-1 RAs may increase the risk of acute optic nerve and retinal complications, particularly NAION and worsening diabetic retinopathy, in susceptible individuals, and close ophthalmic monitoring is recommended for patients with diabetes initiating these agents.

In summary, a Mediterranean or plant-based diet emphasizing green leafy vegetables, fruits, fish, nuts, whole grains, and minimizing processed foods and sugars is optimal for eye health. Depending on your vision needs, there may be some dietary supplements that may be of benefit as well.

I hope this newsletter has been helpful in encouraging you to eat some healthful foods to aid your vision.

In Health,
Natalie