The Aging Eye
Just like every other part of the body, eyes age and do not work as well as we get older. Poor diet, excess sun exposure, toxins, infections, and physical and emotional stressors cause wear and tear on the body, including our eyes. This wear and tear produces free radicals, unstable molecules that harm us at the cellular level. The eyes are prone to damage by free radicals. This damage may result in vision problems, age-related macular degeneration or other eye disorders, but you can help protect your eyes by making healthy food choices.
Antioxidants like vitamin C, vitamin E, vitamin A, beta-carotene, zinc, lutein, zeaxanthin, and omega-3 fatty acids protect against free radical damage that can harm your eyes. You can find these nutrients by eating colorful fruits and vegetables that will protect your eyes and boost your overall health. We’ll take a look at these on the following slides.
Vitamin C and Red Peppers
Vitamin C is a nutrient critical for maintaining good eye health. Vitamin C has anti-inflammatory and antioxidant properties that help decrease the risk of age-related eye disease. The recommended dietary allowance (RDA) of vitamin C for adult women is 75 milligrams per day and 90 milligrams per day for men. Raw red peppers have 95 milligrams of vitamin C per half cup. Other great food sources of the vitamin include orange juice, grapefruit juice, papayas, and strawberries. Vitamin C is heat sensitive and breaks down during cooking. Maximize your intake of vitamin C by eating fruits and veggies that contain these nutrients raw.
Vitamin E in Nuts and Sunflower Seeds
Vitamin E is another antioxidant vitamin that is critical to eye health. Vitamin E is actually comprised of eight fat-soluble antioxidants called tocopherols. These nutrients help protect fats that make up cell membranes. The retina of the eye is rich in fatty acids, so antioxidant protection is critical for the eyes. The RDA for vitamin E is 15 milligrams per day for men and women. One-quarter cup of sunflower seeds contains 12 milligrams of vitamin E. Almonds, peanuts, and peanut butter are also good sources of vitamin E.
Vitamins in Dark, Leafy Greens
Dark, leafy greens like collard greens, kale, and spinach are rich in vitamins C and E. They also have carotenoids called zeaxanthin and lutein. These are nutrients that help protect against age-related macular degeneration (AMD) and cataracts. Lutein and zeaxanthin are found in abundance in the retina and lens of the eye. There is no RDA for zeaxanthin and lutein, but diets that provide 6 milligrams per day of these nutrients have been found to be protective against AMD. One half-cup of cooked kale provides 10.3 milligrams of lutein and zeaxanthin. Broccoli, sweet corn, and romaine lettuce are good sources of these nutrients, too. These foods aren't just good for your eyes, but they help prevent other health problems, too.
Omega-3 Fatty Acids in Salmon
DHA and EPA are beneficial fats known as omega-3 fatty acids. These fats combat inflammation and boost the health of blood vessels. They reduce the risk of age-related macular degeneration and glaucoma. Insufficient levels of these fats may contribute to dry eyes. There is no RDA for DHA and EPA; however, the American Heart Association has recommended intake values for people depending on their prior history of cardiac disease. Those with no history of cardiac disease or heart attack should consume fatty fish or fish oil two times per week. Those who have had a heart attack should consume 1 gram of EPA and DHA per day, either from fish oil or oily fish. Herring, salmon, and sardines provide ample amounts of DHA and EPA. Adequate omega-3 fatty acid intake is part of maintaining good nutrition.
Beta-Carotene in Sweet Potatoes
Beta-carotene is a carotenoid. Carotenoids are red, yellow, and orange pigments in similarly colored fruits and vegetables. Your body converts beta-carotene into vitamin A. In a large study, beta-carotene, zinc, copper, and vitamins C and E reduced the risk of developing age-related macular degeneration. The amount of beta-carotene that study participants took was 17 milligrams daily. There is no RDA for this nutrient, but results of several studies suggest daily intake of between 3 and 6 milligrams is associated with a lower risk of several chronic conditions. Sweet potatoes, pumpkin, carrots, and spinach are good sources of beta-carotene. One-half cup of cooked sweet potatoes provides 15.5 milligrams of beta-carotene.
Zinc in Oysters, Meat, and Poultry
Zinc is a mineral critical for the function of many enzymes in the body. You also need it to maintain healthy eyesight. Zinc functions as an antioxidant, boosts immune function, and is a constituent of cell membranes and proteins in the body. The RDA for zinc is 8 milligrams per day for women and 11 milligrams per day for men. People who eat vegetarian diets absorb less zinc than those who eat meat. Three medium cooked oysters provide nearly 25 milligrams of zinc. Crabs, dark turkey, and dark chicken are other good sources of the important mineral. Zinc deficiency is associated with vision problems, immune system problems, skin problems, and psychological disorders.
Vegetarian Sources of Zinc
Animal products are high in zinc, but plant-based foods also supply this mineral. Beans and legumes are high in fiber, low in fat, and are great sources of vegetarian protein. They also supply zinc. One-half cup of baked beans contains 0.9 milligrams of zinc. One ounce of peanuts supplies the same amount of the mineral. One-half cup of chickpeas or garbanzo beans has 1.3 milligrams of zinc. Other good vegetarian dietary sources of zinc include yogurt, milk, corn flakes, cheese, cereal, cashews, and almonds.
Carotenoids in Eggs
Egg yolks get their vibrant yellow color from carotenoid pigments called lutein and zeaxanthin. These pigment compounds concentrate in a part of the eye called the macula. This is a yellow spot that lies in the center of the retina. The macula controls central vision, which is the part of vision that we use when focusing straight ahead. We rely on central vision to read, drive, and see details sharply. The macular pigment protects the macula from dangerous blue light. It also aids in the function of the macula. Eggs also contain zinc, which helps your body use lutein and zeaxanthin, which are critical for maintaining good eye health.
Nutrients in Squash
Summer squash is full of lutein, zeaxanthin, zinc, and other vitamins that are beneficial for eyesight, including vitamin C. Winter squash provides vitamins A and C and even omega-3 fatty acids, too. One medium summer squash has just 33 calories. It also supplies more than 500 milligrams of potassium. Nutrients in squash help guard against eye problems and vision loss. These nutrients are also available in vision supplements designed to protect ocular health. The National Eye Institute Age-Related Eye Disease Study (AREDS) concluded that use of a supplement formula called the AREDS formula reduces the risk of developing advanced age-related macular degeneration. The formula contains beta-carotene, copper, zinc, and vitamins C and E. A subsequent trial called the Age-Related Eye Disease Study 2 (AREDS2) tested a similar vision supplement formula that replaced beta-carotene with lutein and zeaxanthin and added omega-3 fatty acids. The formula also replaced the high doses of zinc with a lower dose of the mineral. Multivitamins like Ocuvite contain the mix of vitamins, minerals, and other nutrients necessary to help prevent age-related vision problems like advanced AMD.
Nutrients in Broccoli and Brussels Sprouts
Broccoli and Brussels sprouts contain beneficial nutrients like lutein, zeaxanthin, beta-carotene, and vitamins A, C, and E. These are nutrients that act as antioxidants. They scavenge free radicals, unstable molecules that can attack and damage healthy tissue. Retinal tissue is especially susceptible to free radical damage. It is important to eat foods rich in nutrients to protect eye health. If you are at risk for vision problems and blindness, ask your eye doctor if you would benefit from a vision supplement, such as an AREDS2 multivitamin formula.
The Sunshine Vitamin
Vitamin D is a fat-soluble vitamin the body needs to absorb calcium, support bone growth, and modulate immune function and inflammation. There is some evidence that vitamin D also decreases the risk of age-related macular degeneration (AMD). Fatty fish like swordfish, tuna, and salmon contain vitamin D. Cod liver oil contains more. Smaller amounts of the vitamin are found in milk, beef liver, eggs, and cheese. Adult men and women under the age of 70 need 600 international units (IU) of vitamin D per day. By far the best source of vitamin D is the sun. Your skin produces vitamin D when exposed to sunlight. Just be careful not to get burned. Sunburns increase the risk of skin cancer. The more fair-skinned you are, the more careful you need to be about getting too much sun. If you have darker skin and/or live further away from the equator in areas that get less sunlight, ask your doctor if you should take a vitamin D supplement.
Get Your Fill of Folate
Folate is a water-soluble B vitamin that the body needs to repair DNA and produce new cells. It also serves important roles for the function of the nervous system and immune system. Results of some studies suggest that high folate intake decreases the risk of dry age-related macular degeneration (AMD) advancing to geographic atrophy (GA), the late stage of the eye disorder that may lead to blindness. Adult men and women need 400 micrograms (mcg) of folate per day. Women who are pregnant or lactating need more. Get your fill of folate from beef liver, spinach, black-eyed peas, fortified breakfast cereal, and leafy green vegetables.