Maybe you aren’t fond of spinach. Maybe you’re even less fond of its cousin, collard greens. Well, maybe you’ll want to rethink your dinner options and find a way to like these humble these foods can help protect your vision. B. Randy Hammond, Ph.D., who studies eye disease, is certainly convinced. He eats spinach two or three times a week.
Meet Your Macula
Research suggests that you will probably never know to have a macula until something goes wrong with it. It’s the small light-sensitive area in the middle of your retina at the back of your eyeball. These cells take in the image received by the lens and send it to your brain to interpret. Over the years, light can eventually damage the macula, causing small deposits of cellular waste matter to accumulate or small blood vessels under the retina to leak or swell.
The early result of this macular degeneration is difficulty seeing small print and distant objects, and gradual loss of central vision. Macular degeneration is the leading cause of blindness in older Americans, affecting one of three people older than 75. There are two types of macular degeneration-one with leaking blood vessels that can be treated with laser surgery. Ninety percent of people with macular degeneration, however, have the “dry” type that currently has no effective treatment.
Foods That May Help
Enter the carotenoids. These are the yellow, orange, and red pigments that abound in many fruits and vegetables, giving them their bright colors. Carotenoids supply a number of health benefits. Carrots, are packed with beta-carotene. Researchers are now finding that vegetables such as spinach and collard greens may help protect the macula, possibly partly because of two carotenoids in these foods, lutein, and zeaxanthin.
The natural pigment found in the macula protects the macula from light damage by filtering out harmful light rays, points out Dr. Hammond, a professor at Arizona State University in Tempe. “The thicker it is, the less light gets through to harm the macula,” he says. Because macular pigment is made up of lutein and zeaxanthin, the very same stuff found in spinach and collard greens, it was logical for scientists to investigate whether eating more of these vegetable pigments would thicken the macular pigment.
The Eye Disease Case-Control Study Group at five ophthalmology centers studied 876 people between the ages of 55 and 80. Of this group, 356 had macular degeneration. Researchers found that those who ate the most carotenoids were 43 percent less likely to get macular degeneration-and those who ate spinach and collard greens had the least chance of getting the disease.
Learn to Love Greens
A leading researcher of the Eye Disease Case-Control Study Group, Johanna M. Seddon, M.D., of the Massachusetts Eye and Ear Infirmary in Boston, concluded that increasing the carotenoid-containing foods you eat, particularly dark green, leafy vegetables, may decrease the risk of serious age-related macular degeneration.
Dr. Hammond’s studies also support this theory. In one of Dr. Hammond’s studies, 13 people ate spinach daily for 15 weeks. Macular pigment density increased in four weeks for most of them and remained high several months after they stopped eating the spinach.
Get More Zinc
Some studies suggest that zinc intake may also be related to macular degeneration. When Julie Mares- Perlman, Ph D., assistant professor of ophthalmology and visual sciences at University of Wisconsin Medical School, in Madison, studied nearly 2,000 people ranging in age from 43 to 86, she found that people with the highest intake of zinc from food had the lowest risk for early macular degeneration. (You can find zinc in beef, crab, oysters, poultry, and milk.)
Eat More Fruits and Vegetables
Researchers have long suspected that antioxidants, nutrients found in many fruits and vegetables-which combat damage done by unstable “free radical” molecules-may help protect your eyes. A two-year study at Johns Hopkins Hospital in Baltimore, Maryland, involving 976 people found that those with high blood levels of vitamins C and E and beta-carotene were least likely to have macular degeneration.
Stay Away From Fatty Foods
There’s also a possibility that the more saturated fat you eat, the higher the risk for macular degeneration. In the Wisconsin survey, signs of macular degeneration were 80 percent more common in the people who ate the most saturated fat and cholesterol. How could dietary fat affect your eyesight?
It could clog arteries or collect in the retina and slow nutrient supply, explains Dr. Mares-Perlman, the study’s lead author. She stresses, however, that more research is needed before any definitive link is established. We don’t know whether it was the saturated fat content diet, or other aspects of high-fat diets-perhaps low in antioxidants-that was responsible,” she says.
However, because decreasing fat and cholesterol intake has plenty of known benefits, its best, in any case, to cut back on the butter, cheese, cream sauces, fatty meats, chips, and dips.
To Supplement or Not to Supplement
Maybe you truly hate greens or don’t like to take time to cook. Supplements under the “Eye” in your local vitamin store instead? Supplements offer several problems, says Dr. Hammond. When a study shows that spinach or collard greens help prevent macular degeneration. It’s a good guess that the lutein and zeaxanthin are helping, but they could be working with something else in the food.
The food contains many beneficial compounds that we cannot measure that may actually be the compound of importance,” says Sheila West, Ph.D., associate professor of ophthalmology at the Johns Hopkins University School of Medicine in Baltimore, Maryland. There are two other points to keep in mind. First, studies show that vitamins and minerals alone don’t do the job:
In the Eye Disease Case-Control Study. Which showed the benefit of spinach and collard greens, supplementing with vitamin A, E, or C didn’t have a significant effect.
The Johns Hopkins study that linked high blood levels of certain vitamins to less risk of macular degeneration found that using vitamin supplements showed no benefit. And, second, the results of the effects of many nutrients aren’t definitive.
A Japanese study showed that 35 people with macular degeneration had lower zinc and vitamin E blood levels than 66 people without eye damage, suggesting that low levels of these nutrients are linked with macular degeneration. Conversely, however, a study of 312 people at the Australian National University showed no relation between levels of vitamin E and beta-carotene in the blood and macular degeneration.
Another Australian study, from Sydney University, found no link between levels of vitamin E in the blood and rates of macular degeneration, and only a weak suggestion that selenium levels in smokers might be linked to the disease. What does all this mean? It means no one knows yet exactly what nutrients may help your eyes.
Experts agree that many of us are low in specific nutrients. A large ongoing study at the DVA Medical Center in Chicago showed that people with macular degeneration have a low intake of vitamin E, magnesium, zinc, vitamin B6, and folic acid. But most experts say that the answer is a diet high in fruits and vegetables-not supplements.
There are lots of other food components that have health benefits,” says Dr. Mares-Perlman.”And some nutrients in the form of a supplement aren’t very usable by your body.” Dr. Hammond advises people to increase their intake of lutein- and zeaxanthin-containing foods such as spinach and other dark green leafy vegetables.
If despite your best efforts to pack in nutrients, you’re concerned that you’re not getting enough, experts agree that it’s generally safe to add a multivitamin and mineral supplement. You should never, however, take any other supplement without checking with your doctor.
If you have macular degeneration, you should be under the care of your doctor. Do eat a balanced diet rich in fruits and vegetables and low in fatty foods and cholesterol.