John McComas, 46, looks forward to watching his wife grow old with him and hopes to see his two teenage daughters graduate from high school and college. But, if he ends up like his father and grandfather, McComas, a sales representative, will be lucky if he can witness anything beyond age 50. Age-related macular degeneration, a condition that is the leading cause of legal blindness in people older than 60, runs in his family. "I want to do all I can to prevent this disease from stealing my sight," McComas says. "One day, I'd like to see my grandchildren clearly, a luxury my father did not enjoy."
If you have the same concerns, read on as Liam McClintock, ND, LAc, the founder of Rising Tide Natural Medicine in Yarmouth, Maine, and Natural Resources in Boulder, Colorado, answers questions McComas posed on how to prevent and treat this degenerative disease, which affects more than 10 million Americans.
Q. John McComas: I've heard that macular degeneration has different phases. What are they?
A. Liam McClintock, ND, LAc: The "dry" phase of macular degeneration occurs when the retinal pigment epithelium breaks down and interferes with the metabolism of the retina and the retina thins. Most people with mild dry macular degeneration will never have disabling central vision loss. However, there is no way to predict who will progress to a more severe form of the disease. If the disease gets worse, it may promote new blood vessel formation and fluid leakage (the "wet" phase). The wet form of macular degeneration often leads to significant vision loss like that suffered by your father and grandfather.
Q. What symptoms should I look out for?
A. Symptoms of macular degeneration include blurred, distorted, dim, or absent central vision. Among the ultimate effects of macular degeneration is central vision loss, but peripheral fields remain intact. Although this disease by itself never results in complete blindness, you may not be able to perform tasks that require central visual acuity, such as reading or driving, as well as before. If you're concerned, consult your doctor, who can perform tests to gauge your risk and monitor any worsening of the disease.
Q. Who's at risk?
A. Everyone has some risk of getting macular degeneration. The disease becomes increasingly common among people over age 50. By age 75, nearly 15 percent of people have this condition. Other important risk factors are family history, cigarette smoking, and being Caucasian. Protecting the eyes from ultraviolet radiation can help keep the disease from accelerating due to oxidative damage. Also, it helps to treat concurrent medical conditions, such as diabetes and high blood pressure, that are known to cause deterioration of the retina, glaucoma, and cataracts.
Q. Will any vitamins or supplements help prevent or slow the disease?
A. Zinc has been shown to slow the progression of dry macular degeneration, but other studies have shown the supplement to be less effective in the late-developing wet form. Typically, zinc is best absorbed in the form of citrate or picolinate and can be taken in doses near 50 mg per day. When you take higher amounts of zinc (above 50 mg) over an extended period of time, you should also take copper to prevent its depletion.
Also, studies show that taking lutein significantly improves vision in subjects with both early and advanced stages of macular degeneration. Although results have been mixed, some research has demonstrated an improvement in those taking a combination of zinc, copper, manganese, selenium, vitamin E, vitamin C, riboflavin, and beta-carotene.
Q. Can certain foods help, too?
A. A higher intake of saturated fat and cholesterol may be associated with an increased risk for macular degeneration, so avoid the burgers and fries to save your healthy eyes. On the other hand, eating fish, which contains important omega-3 fatty acids, more than once per week has been shown to reduce the risk of developing age-related macular degeneration by 50 percent.
Some studies have linked beer consumption with the disease, but other studies have shown that moderate wine consumption may reduce macular degeneration risk, likely because wine, and especially red wine, is rich in antioxidants. Antioxidants that have proven to be most effective at preventing oxidative damage in the eye, and hence macular degeneration, are lutein and zeaxanthin, both carotenoids found in particularly high concentrations in collards, kale, and spinach.
Denver-based freelance science and health writer Anne Burnett is a frequent contributor to Delicious Living.