Pills vs. Food
Although antioxidant supplements are routinely prescribed to people with early signs of macular degeneration, there’s little agreement on whether supplements will help otherwise healthy people preserve their vision. “Most of the evidence to date is very mixed,” Allen Taylor, a leading researcher at the Laboratory for Nutrition and Vision Research at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, tells WebMD. In one recent study, for example, a multivitamin seemed to protect against some forms of cataracts but actually raise the risk of other forms.
"By far the best way to protect your vision from age-related diseases is by eating a healthy diet," says Kathleen Zelman, RD.
Recent findings help make the case for healthy food choices. A study by French scientists, for instance, found eating more vegetables -- including cabbage, broccoli, pepper, corn, or spinach -- improved the condition of the retina in people with age-related macular degeneration.
The Healthiest Diet Pattern for Healthy Eyes
The overall pattern of your diet may be even more important than single foods. Allen Taylor and his colleagues at the Jean Mayer USDA Human Nutrition Research Center on Aging reported a link between AMD and high-glycemic index foods, such as sugar and refined carbohydrates such as pasta and white bread. "We suspect that proteins in cells in the eye become toxic when exposed to high-glycemic index foods, leading to AMD-related injury," Taylor tells WebMD.
If high-glycemic index foods pose a risk, whole and unprocessed foods appear to protect the eyes. The healthiest diet of all may be the Mediterranean diet, which features fruits, vegetables, nuts, whole grains, fish, and heart-healthy oils. A study reported in the Archives of Ophthalmology tracked nearly 2,500 adults over 10 years. The volunteers filled out questionnaires about what they ate. Those who ate fish and nuts frequently had a lower risk of developing AMD by 30% or more. A second study, which included 6,734 older adults tracked for 10 years, found that adults who ate more foods with trans fats (typically found in baked or processed foods) were more likely to develop late-stage AMD. In contrast, those who consumed more olive oil -- a staple of the Mediterranean diet -- had a lower risk.
The Diabetes Connection
Age-related macular degeneration is just one threat to vision. Another serious danger and a leading cause of blindness is diabetic retinopathy. A consequence of diabetes, diabetic retinopathy occurs when blood vessels in the retina are irreversibly damaged.
Researchers don’t yet understand all the factors that lead to blood vessel damage in diabetics. "But it’s clear that food choices that lower your risk of developing type-2 diabetes will help lower the risk of diabetic retinopathy," says Roy. Here, too, a Mediterranean-style diet appears to offer protection. Research from the University of Melbourne in Australia reported that the Mediterranean-style eating pattern can even improve blood sugar control in people with type 2 diabetes.