Older Americans are concerned about their vision, and rightly so. Degenerative eye conditions, especially cataract and age-related macular degeneration, become increasingly common as we age.
About one-fourth of us over age 65 have early signs of macular degeneration in our retinas that place us at increased risk for progressing to advanced macular degeneration over the next 10 years. Advanced age-related macular degeneration, AMD, which eventually destroys central vision, is the most common cause of legal blindness and visual impairment in older Americans. The National Eye Institute estimates that 1.6 million seniors have advanced AMD and 8 million are at risk of losing vision from this condition over the next five years.
In addition, by age 75, most of us will have to deal with either cataract surgery or a vision-limiting cataract by curtailing activities, such as driving.
Treatments are expensive. AMD drains $570 million every year in direct medical costs; cataract surgery has been the single most expensive line item in the Medicare budget.
Fortunately, the past two decades of research suggest measures we can take to protect both our eyes and budgets. Payback could be enormous: Former National Eye Institute director Dr. Karl Kupfer estimated that slowing the development of cataracts by 10 years could cut the number of needed surgeries in half.
Epidemiological studies, including many right here in Wisconsin, suggest we can markedly modify risk for cataracts and AMD by avoiding smoking and eating nutrient-rich diets. Two such studies indicate that even modestly above-average diets halve the likelihood of getting the most common type of cataract. Other recent studies suggest that physical activity cuts the risk of AMD; the impact of combining lifestyle changes could be dramatic.
It is tempting to search for a “magic bullet” — a single supplement or medication that would correct a problem such as age-related eye disease. Yet the science more strongly supports the benefit of eating foods that are rich in a variety of nutrients and protective plant chemicals than taking supplements.
The Age-Related Eye Disease Study demonstrated that a specific supplement containing antioxidants and zinc slowed the progression of AMD by 25 percent over six years. A Dutch study, however, showed that people whose diets were high in the same antioxidants but from foods, at much lower levels, had 35 percent lower progression rates of AMD over eight years.
What types of diets might be high in the antioxidants and zinc that are contained in AREDS supplements? They would be likely to include an abundance of colorful vegetables and fruits that supply vitamins C, E and beta-carotene, as the supplement did; adequate zinc, which typically comes in a variety of high-protein foods (beans, fish, dairy, meat, eggs) and in whole refined grains; and low levels of fat, refined grains and/or sugar, which reduce the punch that can be packed into calories. In addition, such diets, because they are high in plant foods, would also be high in many other phytochemicals that may protect the eye by their antioxidant, anti-inflammatory or light-absorbing properties.
These general criteria are met by many recommended diet patterns, including Mediterranean diets, low-fat diets or low-carbohydrate diets, or diets that adhere to the U.S. Dietary Guidelines, even though specific foods emphasized by these patterns vary.
As the eye, so the body. Research in the past decade indicates that healthy diet patterns are related to lower blood pressure, inflammation and overall mortality from cardiovascular disease and cancer.
Eating this way need not be costly, especially compared to the economic consequences of not doing so. For example, beans and eggs are both low-cost protein sources rich in other nutrients. Vegetables are especially inexpensive if we grow them ourselves. Programs to support local agriculture and community gardens can go a long way in facilitating skills and resources needed to grow fruits and vegetables.
Eating healthy foods (as opposed to highly processed foods high in sugar, refined grains and fat) sustains our land and our local economies as well as our health, especially when we buy food grown using sustainable processes and buy locally and in season.
Healthy lifestyles may also sustain our health care system. Tom Daschle pointed out early in the health care reform debate that our current health care system spends most on costly treatment for end-stage conditions, and very little on prevention. In his book “Critical: What We Can Do About the Health Care Crisis” he opines that “a reformed health care system should be aggressive in promoting prevention.” Let us hope that someday it will.
Until then, we do well to enact our own personal “health care reform.” Considering future economic implications, we might even consider it our patriotic duty to do so. We need, individually and collectively, to cultivate a new “vision” of health, less blurred by marketing hype, confusion and lack of a sense of personal empowerment.
Julie Mares is a nutrition professor in the department of ophthalmology and visual sciences in the University of Wisconsin-Madison’s School of Medicine and Public Health.