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Don’t look now, but your eyesight may be failing. More Americans are at risk for losing their sight in the coming years because aging baby boomers make up a big chunk of the population, and the risk of eye disease increases with age. Two of the main threats to aging eyes are cataracts and age-related macular degeneration (AMD). But the key to preventing blindness from cataracts and AMD may be staring at you from your dinner plate.
Cataracts are cloudy, milky spots that form on the normally clear lens of the eye, which are often caused by decreased levels of antioxidants in the lens. A study in the Critical Review of Food Science and Nutrition said regular servings of antioxidant-rich foods can help keep cataracts from forming. Which ones are the best? The American Journal of Epidemiology (1998, volume 147) reported that broccoli, corn, kale, spinach, and tomato sauce are the most protective against cataracts because they abound with the antioxidants glutathione and vitamin C.
Age-related macular degeneration is the leading cause of blindness for Americans over the age of 65. The macula is the part of the retina that focuses an image and is vulnerable to oxidation damage. Approximately 95 percent of AMD occurs when the inner layer of the retina accumulates waste material from oxidation, which then leads to loss of vision from the center of the eye outward.
The macula is made up of the key carotenoids lutein and zeaxanthin, which are not synthesized by the body and must be supplied through a proper diet. The higher the levels of lutein and zeaxanthin, the greater the serum concentrations of macular pigment, a retina protectant. Research at Florida International University in Miami found a direct relationship between dietary intake of lutein and zeaxanthin and increased density of macular pigments. And a study by the National Institutes of Health showed that a higher carotenoid intake was associated with a lower risk of AMD.
Spinach, kale, and collard greens are some of the foods richest in lutein. Mangoes, corn, sweet potatoes, carrots, squash, tomatoes, and bok choy are also good sources. Zeaxanthin is found in spinach, corn, orange bell peppers, and honeydew melon. These foods may not only curb oxidative damage but may also reverse some of its effects. Research at the DVA Medical Hospital of North Chicago tested 14 male patients aged 61 to 79 and showed between a 60 and 92 percent improvement in vision with the addition of four to seven servings of spinach per week.