Your eyesight is probably the most important of your five senses.Eye health goes hand-in-hand with general health, but there are a few nutrients that are especially important for the eyes.These nutrients help maintain eye function, protect the eyes against harmful light and reduce the development of age-related degenerative diseases.
This article lists the main nutrients that will maximize your eye health, their dietary sources and potential benefits.
1. Vitamin A
Vitamin A deficiency is one of the most common causes of blindness in the world .This vitamin is essential for maintaining the eyes' light-sensing cells, also known as photoreceptors.If you don't consume enough vitamin A, you may experience night blindness, dry eyes or more serious eye diseases, depending on how severe your deficiency is .
Vitamin A is only found in animal-derived foods. The richest dietary sources include liver, egg yolks and dairy products.However, you can also get vitamin A from antioxidant plant compounds called provitamin A carotenoids, found in high amounts in some fruits and vegetables.Provitamin A carotenoids provide around 30% of people's vitamin A requirements, on average. The most efficient of them is beta-carotene, which is found in high amounts in kale, spinach and carrots .
2–3. Lutein and Zeaxanthin
Lutein and zeaxanthin are yellow carotenoid antioxidants known as macular pigments.This is because they are concentrated in the macula, the central part of the retina. The retina is a layer of light-sensitive cells on the back wall of the eyeball.Lutein and zeaxanthin act as a natural sunblock. They're thought to play a central role in protecting the eyes against harmful blue light .
Egg yolks, sweet corn and red grapes may also be high in lutein and zeaxanthin .In fact, egg yolks are considered to be one of the best sources because of their high fat content .Carotenoids are better absorbed when eaten with fat, so it is an excellent idea to add some avocado or healthy oils to your leafy vegetable salad .
4. Omega-3 Fatty Acids
The long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are important for eye health.DHA is found in high amounts in the retina, where it may help maintain eye function. It is also important for brain and eye development during infancy. For this reason, DHA deficiency can impair vision, especially in children .
Evidence also shows that taking omega-3 supplements may benefit those with dry eye disease .Dry eye disease occurs when the eyes don't form enough tear fluid. This causes the eyes to become excessively dry, leading to discomfort and visual problems.
The best dietary source of EPA and DHA is oily fish. Additionally, omega-3 supplements derived from fish or microalgae are widely available.
5. Gamma-Linolenic Acid
Gamma-linolenic acid is an omega-6 fatty acid found in small amounts in the diet.
The richest sources of gamma-linolenic acid are evening primrose oil and starflower oil.Some evidence suggests that taking evening primrose oil may reduce the symptoms of dry eye disease.
6. Vitamin C
The eyes require high amounts of antioxidants — more so than many other organs.
The antioxidant vitamin C appears to be especially important, although controlled studies on its role in eye health are lacking.The concentration of vitamin C is higher in the aqueous humor of the eye than in any other body fluid. The aqueous humor is the liquid that fills the outermost part of the eye.
The levels of vitamin C in the aqueous humor are directly proportional to its dietary intake. In other words, you can increase its concentration by taking supplements or eating foods rich in vitamin C .High amounts of vitamin C are found in many fruits and vegetables, including bell peppers, citrus fruits, guavas, kale and broccoli .
7. Vitamin E
Vitamin E is a group of fat-soluble antioxidants that protect fatty acids from harmful oxidation.
Since the retina is highly concentrated in fatty acids, adequate vitamin E intake is important for optimal eye health .
The best dietary sources of vitamin E include almonds, sunflower seeds and vegetable oils, such as flaxseed oil .
The eyes contain high levels of zinc .
Zinc is a part of many essential enzymes, including superoxide dismutase, which functions as an antioxidant.Zinc also appears to be involved in the formation of visual pigments in the retina. For this reason, zinc deficiency may lead to night blindness .