It’s easy to take your ability to see well for granted until you lose it. No, we’re not talking about grabbing your reading glasses to see the menu in a dimly lit restaurant – but more serious vision problems that rob you of your ability to see. Two of the most common causes of age-related visual loss are a condition called age-related macular degeneration and cataracts. Fortunately, there’s growing evidence that diet plays a role in whether you develop either of these eye diseases.
What is age-related macular degeneration (AMD)? First, how does your vision work? It’s your retina, a light-sensitive tissue in the back of your eyes that converts the light you see into signals your brain can process. Once these signals reach your brain through the optic nerve, the brain translates them into visual information you can see. In the center of the retina is an area called the macula. It’s this part of your eye that is responsible for central vision. Age-related macular degeneration attacks the macula, slowly destroying it. As you might expect, this makes things you see in the center of your eyes blurry. Eventually, AMD can progress to complete blindness.
Cataracts, you’re probably familiar with. With this common, age-related condition, the lens in the eye becomes cloudy and opaque. When you have cataracts, the world looks cloudy and lackluster, as if there’s a gray film covering it. Cataracts are the most common cause of visual loss in people over the age of 40. Chances are, you know someone who has had cataracts. Fortunately, they can usually be surgically corrected – but isn’t it better to prevent them? Although genetics is a factor with visual loss, there’s lots of evidence that diet lowers the risk of AMD and cataracts.
Preventing Age-Related Macular Degeneration and Cataracts
The macula of your eye, the portion that’s affected by age-related macular degeneration is made up of zeaxanthin and lutein, compounds called carotenoids. Guess where you find carotenoids naturally? In a variety of fruits and vegetables. In fact, the job of carotenoids in the macula of the retina is to absorb ultraviolet light from the sun and protect the retina from damage. So, it makes sense that getting more carotenoids in your diet might give your retina additional protection against damage. Those extra carotenoids absorb UV light so that the delicate tissues in your retina aren’t harmed by it. Exposure to ultraviolet light plays a role in both age-related macular degeneration and cataracts.
Carotenoids are only one dietary component that could play a protective role against visual loss. The mineral zinc may too and the antioxidant vitamins A, C, and E as well. The reason antioxidant vitamins, like A, C, and E, are important is that oxidative stress likely plays a role in these eye diseases. These vitamins help to counteract oxidative stress.
Supporting the idea that carotenoids protect against age-related macular degeneration is a study published in JAMA of Ophthalmology showing those who consumed the most carotenoid-rich foods had a 25% to 35% lower risk of developing this common disease compared to those who ate the least. Another study showed a 40% reduction in age-related macular degeneration in people with the highest carotenoid intake.
Most of the studies looked at the intake of specific carotenoids, including common ones like zeaxanthin, lutein, and beta-carotene but there are more than 600 pigments in the carotenoid family. Although lutein and zeaxanthin are the carotenoids in the retina, it’s possible that other carotenoids may be of benefit as well. That’s why the best way to get this class of eye-protective nutrients is naturally – from the foods you eat.
Sources of Carotenoids
Of course, you want to protect your vision – so what foods should you eat? Carotenoids are most abundant in orange fruits and vegetables, such as carrots, sweet potato, and pumpkin, while green, leafy vegetables also have high quantities of carotenoids. The reason leafy vegetables don’t look orange is that the chlorophyll in these foods masks the orange pigment. Considering that antioxidants and carotenoid pigments may offer eye-protective benefits, the best approach is to eat a wide variety of fruits and vegetables since all vegetables contain antioxidants that may be beneficial. There’s also some evidence that getting more of the omega-3 fatty acid DHA in fatty fish might offer protection against age-related macular degeneration because these fats reduce inflammation. However, a recent study didn’t support this.
How about Cataracts?
According to research and the American Optometric Association, adding more vitamin C to your diet may lower your risk of cataracts. There’s also evidence that vitamins C and E, both antioxidants, slow the progression of cataracts. As with age-related macular degeneration, adding more carotenoids (lutein and zeaxanthin in particular) may reduce the risk as well. If everyone ate five or more servings of fruits and vegetables daily, the incidence of cataracts and AMD would likely plummet. Produce isn’t just healthy for your heart but for your brain and vision as well.
Other Ways to Lower Your Risk of Visual Loss
Diet is one of the biggest factors in terms of protecting your eyes. Another big one is shielding your eyes from ultraviolet light. Make sure you’re wearing a pair of sunglasses that offers full protection against ultraviolet light and wear them religiously. It doesn’t hurt to wear a cap too when you’re out in direct sunlight – anything to reduce the amount of ultraviolet light that hits the retina in the back of your eyes. Finally, if you smoke, kick the habit. Smokers are more prone towards cataracts and, possibly, age-related macular degeneration as well.
The Bottom Line
It’s nice to know that you can lower your risk of visual problems by eating a healthy diet. Now you have another reason to eat your fruits and vegetables.
Dev Ophthalmol. 2005;38:70-88.
JAMA Ophthalmol. 2015 Dec;133(12):1415-24. doi: 10.1001/jamaophthalmol.2015.3590.
Harvard T.H. Chan School of Public Health. “Pigments in colorful vegetables may ward off macular degeneration”
Medscape Family Medicine. “Do Omega-3 Fatty Acids Help Prevent AMD?”
American Optometric Association. “Nutrition and Cataracts”
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