Your eyes are complex organs that need many different vitamins and nutrients to function properly. Common conditions, such as diabetic retinopathy, age-related macular degeneration, glaucoma and cataracts, can impact your eyes. Though a variety of different factors causes these conditions, nutrition seems to have an influence on all of them — at least in part. Here are 9 key vitamins and nutrients that help maintain eye health.

1. Vitamin A

Vitamin A plays a crucial role in vision by maintaining a clear cornea, which is the outside covering of your eye. This vitamin is also a component of rhodopsin, a protein in your eyes that allows you to see in low light conditions (1Trusted Source). Vitamin A deficiency is rare in developed countries, but if unaddressed can lead to a serious condition called xerophthalmia. Xerophthalmia is a progressive eye disease which begins with night blindness. If vitamin A deficiency continues, your tear ducts and eyes can dry out. Eventually, your cornea softens, resulting in irreversible blindness (1Trusted Source, 2). Vitamin A may also help protect against other eye afflictions. Some studies suggest that diets high in vitamin A may be associated with a reduced risk of cataracts and age-related macular degeneration (AMD) (3Trusted Source, 4Trusted Source, 5Trusted Source, 6Trusted Source). For general eye health, vitamin-A-rich foods are recommended over supplements. Sweet potatoes are an excellent source, as are leafy green vegetables, pumpkins and bell peppers (1Trusted Source).

2. Vitamin E

Many eye conditions are believed to be associated with oxidative stress, which is an imbalance between antioxidants and free radicals in your body (7Trusted Source, 8Trusted Source). Vitamin E is a potent antioxidant that helps protect your cells — including your eye cells — from damage by free radicals, which are harmful, unstable molecules. One seven-year study in 3,640 people with AMD showed that taking 400 IU of vitamin E and several other nutrients in a daily supplement called AREDS reduced the risk of progressing to advanced stages by 25% (9Trusted Source). In addition, some studies suggest that diets high in vitamin E may help prevent age-related cataracts. However, more research is needed as some studies show no association between vitamin E and this condition (10Trusted Source). Nonetheless, a diet that includes adequate vitamin E is recommended to maintain proper eye health. Some vitamin-E-rich options include nuts, seeds and cooking oils. Salmon, avocado and leafy green vegetables are also good sources.

3. Vitamin C

Like vitamin E, vitamin C is a powerful antioxidant that may protect your eyes against damaging free radicals (11Trusted Source). Vitamin C and several other nutrients are used in the supplement AREDS, which may benefit those with AMD. When taken daily, one study suggests that AREDS may reduce the risk of this condition progressing by 25% (9Trusted Source). In addition, vitamin C is required to make collagen, a protein that provides structure to your eye, particularly in the cornea and sclera (12Trusted Source). Several observational studies suggest that vitamin C may help lower your risk of developing cataracts, a condition that causes your eye to become cloudy and impairs vision (13Trusted Source). For example, one observational study showed a 75% reduced risk of developing cataracts when the daily vitamin C intake was above 490 mg, compared to 125 mg or less (14Trusted Source). Another study found that regular vitamin C supplements may reduce the risk of cataracts by 45% (15Trusted Source). Citrus and tropical fruits, bell peppers, broccoli and kale contain particularly high amounts of vitamin C, making them great options to boost your daily intake.

4. Vitamins B6, B9 and B12

Researchers have also studied several B vitamins for their impact on eye health, particularly vitamins B6, B9 and B12. This combination of vitamins can lower levels of homocysteine, a protein in your body that may be associated with inflammation and an increased risk of developing AMD (16Trusted Source). A clinical study in women demonstrated a 34% reduced risk of developing AMD while taking 1,000 mcg of vitamin B12 along with vitamins B6 and B9 (17Trusted Source). However, more research is needed to confirm the benefits of these supplements. In addition, it’s unclear if increasing your intake of vitamin-B-rich foods would have similar effects.

5. Riboflavin

Another B vitamin studied in relation to eye health is riboflavin (vitamin B2). As an antioxidant, riboflavin has the potential to reduce oxidative stress in your body, including your eyes (18). In particular, scientists are studying riboflavin’s potential to prevent cataracts, as prolonged riboflavin deficiency may lead to this condition. Interestingly, many individuals with cataracts also are deficient in this antioxidant (19Trusted Source, 20Trusted Source). One study found a 31–51% decreased risk of cataracts development when participants’ diets included 1.6–2.2 mg of riboflavin per day, compared to .08 mg per day (21Trusted Source). Health authorities recommend consuming 1.1–1.3 mg of riboflavin per day. It’s usually easy to achieve this amount, as many foods are high in riboflavin. Some examples include oats, milk, yogurt, beef and fortified cereals (19Trusted Source).

6. Niacin

The main function of niacin (vitamin B3) in your body is to help convert food into energy. It can also act as an antioxidant (22). Recently, studies have suggested that niacin may play a role in the prevention of glaucoma, a condition in which the optic nerve of your eye becomes damaged (23). For example, an observational study on the nutrient consumption of Korean adults and their risk for glaucoma found an association between low dietary intake of niacin and this condition (24Trusted Source). In addition, an animal study showed that high doses of niacin supplements were effective in preventing glaucoma (25Trusted Source). Overall, more research on the potential link between niacin and glaucoma is needed. Supplements should be used with caution. When consumed in high amounts of 1.5–5 grams per day, niacin may pose adverse effects to the eyes, including blurred vision, macular damage and inflammation of the cornea (26Trusted Source, 27Trusted Source). However, there is no evidence that consuming foods naturally high in niacin has any adverse effects. Some food sources include beef, poultry, fish, mushrooms, peanuts and legumes.

7. Lutein and Zeaxanthin

Lutein and zeaxanthin are part of the carotenoid family, a group of beneficial compounds synthesized by plants. Both of these carotenoids can be found in the macula and retina of your eyes, where they help filter potentially harmful blue light, thus protecting your eyes from damage (28Trusted Source). Several studies suggest that these plant compounds may prevent cataracts and prevent or slow the progression of AMD (29Trusted Source, 30Trusted Source). A randomized, controlled study found potential benefits of lutein for people with cataracts. Over two years, those taking supplements containing 15 mg of lutein three times per week experienced improvements in vision (31Trusted Source). Recommended daily intakes and safe supplemental doses have not been established for these compounds. However, up to 20 mg of lutein per day for 6 months has been used in studies without adverse effects (32). Nonetheless, supplements may not be necessary. As little as 6 mg of lutein and zeaxanthin may yield benefits, and a diet rich in fruits and vegetables naturally provides this amount. Cooked spinach, kale and collard greens are particularly high in these carotenoids (32).

8. Omega-3 Fatty Acids

Omega-3 fatty acids are a type of polyunsaturated fat. The cell membranes of your retina contain a high concentration of DHA, a particular type of omega-3 (33Trusted Source). Besides helping form the cells of your eye, omega-3 fats have anti-inflammatory properties which may play a role in the prevention of diabetic retinopathy (DR). A review of 31 studies suggested that diets high in oily fish — such as the traditional Mediterranean diet — may protect against DR. Although these findings need to be corroborated with more research, they imply that fatty acids may be responsible (34Trusted Source). Omega-3 fats may also benefit individuals with dry eye disease by helping them produce more tears. With this condition, a lack of tears causes dryness, discomfort and occasional blurry vision (33Trusted Source, 35Trusted Source, 36Trusted Source). To increase omega-3 fatty acids in your diet, include rich sources such as fish, flaxseed, chia seeds, soy and nuts. Omega-3s can also be found in cooking oils such as canola and olive oil.

9. Thiamine

Thiamine, or vitamin B1, plays a role in proper cell function and converting food into energy (37Trusted Source). It’s possibly effective at reducing the risk of cataracts (38Trusted Source, 39Trusted Source). An observational study in 2,900 people in Australia suggests that a diet high in thiamine reduces your risk of developing cataracts by 40%. This study also indicates that protein, vitamin A, niacin and riboflavin may protect against cataracts (38Trusted Source). What’s more, thiamine has been proposed as a potential treatment for the early stages of DR. A clinical study found that 100 mg of thiamine taken three times daily reduced the amount of albumin in urine — an indication of DR in type 2 diabetes (40Trusted Source). Food sources of thiamine include whole grains, meat and fish. In addition, thiamine is often added to foods like breakfast cereals, bread and pasta (37Trusted Source).

The Bottom Line

Research suggests that certain vitamins and nutrients may help prevent or slow the progression of several different eye conditions. Supplements may be beneficial if you suspect you’re missing any of these vitamins in your diet. However, eating a balanced diet rich in fruits, vegetables, whole grains, protein and healthy fats will provide you with all the nutrients your eyes — and the rest of your body — need for optimal health.