Information Sheet For Macular Degeneration
The Age-Related Eye Disease Study (AREDS) was a major clinical trial sponsored by the National Eye Institute, one of the Federal government’s National Institutes of Health. The study confirmed that a diet with high levels of antioxidants and zinc reduces the risk of advanced age-related macular degeneration (AMD) by about 25 percent in some AMD patients.
The supplements are not a cure for AMD, nor will they restore vision already lost from the disease. However, they may play a key role in helping people at high risk for developing advanced AMD keep their vision.
The daily amounts of antioxidants and minerals shown to be the most effective were 500 milligrams of vitamin C; 400 International Units of vitamin E; 28,640 International Units of vitamin A (beta-carotene); 80 milligrams of zinc; and 2 milligrams of copper.
Many vitamin manufacturers have brands that advertise the same vitamin supplement combination as used in the AREDS study. Most brands are available locally or through the internet. Prices usually range from $10.00 to $36.00 per bottle.
Another study, conducted by the Harvard School of Medicine, showed that dietary lutein and zeaxanthin play an essential role in protecting the retina from the damaging effects of light. Zeaxanthin and lutein were not commercially available when the AREDS began and were, therefore, not included in that study. Your physician can explain more about the benefits of lutein and zeaxanthin. Many other supplements claim to benefit AMD without real scientific evidence.
Doctors at Retina Consultants of Southwest Florida have advocated the use of certain antioxidants for AMD. We are pleased that the results of this study support the recommendations that we have been making for 20 years.
Patients should discuss the use of these high levels of supplements with their family doctor before use. High dosages of vitamins can have a negative effect on certain health conditions. Patients taking blood thinners, such as the drug Coumadin (Warfarin), should not take vitamin E without consulting the prescribing physician. Other studies indicate that prolonged use of Vitamin A could lead to bone loss and possible bone fractures, and a slight increase in mortality related to cardiac disease. Patients who smoke should not take beta-carotene. Studies have shown beta-carotene may increase the risk of lung cancer in smokers. High levels of zinc may cause anemia. Copper supplements should be included whenever taking high levels of zinc to prevent copper deficiency. If you are already taking vitamin supplements, especially zinc or vitamins A or E, please consult your family physician before taking additional vitamins. Excess dosages of supplements may be harmful. A recent study found a possible increase in mortality with high dose vitamin E. Some minor side effects were reported from the AREDS study treatments.