Prevention
Dietary Supplements
Age-Related Eye Disease Study (AREDS)
In 2001, the National Eye Institute completed a 10-year clinical study to evaluate the effects of a high-potency antioxidant vitamin and mineral supplement on AMD.
Results of this large-scale clinical trial showed that patients at high risk of developing advanced AMD reduced that risk 25 percent by taking the complete formulation of antioxidants and zinc. For this same group, the risk of vision loss itself was reduced by 19 percent. Those at high risk include people with intermediate AMD (e.g. presence of large drusen) in one or both eyes or those with advanced AMD in one eye already.
Only a few minor side effects from taking the study medications were found.
Recommendations
(1) If you are at high risk of developing advanced AMD, you should consider taking supplements like those used in AREDS. Supplements provide no apparent benefit for those with early AMD or no AMD, and there is no apparent need to take them. However, yearly eye examinations are advisable to determine if the disease is progressing.
(2) Your eye doctor can tell you if you have the high-risk level of AMD by performing an eye examination including a retinal examination through dilated pupils.
(3) Because the AREDS formulation has a high level of antioxidants and zinc, talk to your eye doctor or primary care physician before starting the regimen. This is especially important for individuals with chronic diseases for which they may be taking several medications.
(4) Bausch & Lomb, the company that prepared the study formulation, markets the supplement under the name PreserVision. It is available over-the-counter in pharmacies and other stores that sell dietary supplements. Other AREDS supplements are also available.
PreserVision is available in two forms – the original AREDS formula and a formula with lutein, which replaces the beta-carotene in the original PreserVision formula. Smokers are advised to use this latter formula because other studies have found that beta-carotene may increase the risk of health problems in smokers.
As an alternative, the ingredients can be purchased separately. The individual supplements and the recommended amount to be taken daily are:
Vitamin C – 500 milligrams
Vitamin E – 400 International Units (IU)
Beta-carotene – 15 milligrams (25,000 IU) – not recommended for smokers
Zinc – 80 milligrams and Copper – 2 milligrams (must be included when taking zinc)
Lutein (optional) – 10 milligrams
Zeaxanthin (optional) 2 milligrams
Age-Related Eye Disease Study 2 (AREDS2)
The National Eye Institute is conducting a second large-scale, long-term study to refine the findings from the original study and to assess the effects of high supplemental doses of lutein and zeaxanthin and omega-3 fatty acids for the treatment of AMD and cataract. Research suggests that lutein and zeaxanthin (pigments found in green, yellow and orange fruits and vegetables) may help protect against macular degeneration, although this has not been proven.
Omega-3 fatty acids found in such cold-water fish as salmon and tuna, as well as in fish oil capsules are important in the management of heart disease. Preliminary research also suggests they may be a protective factor in AMD.
Until now, however, there has been no data to prove that the risk of AMD can be reduced by taking large amounts of any of these nutrients. To address this unanswered question, approximately 4,000 patients in AREDS2 are receiving a placebo, lutein and zeaxanthin, omega 3 fatty acid, or all three nutrients assigned in a randomized fashion. AREDS2 is also studying the feasibility of taking a smaller amount of zinc than what was used in the original AREDS formulation.
The study is being conducted in clinical centers around the United States, including Devers Eye Institute in Portland.
A Healthy Diet
Eating whole, natural foods is considered the safest and most effective way to obtain eye-healthy nutrients. Try to eat several servings a day of fruits and vegetables. These foods include green leafy vegetables and other yellow, orange and green fruits and vegetables. Two or more servings of fish each week, such as salmon, tuna or sardines, or two to three one-gram capsules of fish oil per day will supply omega-3 fatty acids. For overall health, a diet low in cholesterol, saturated and trans fat, sugar and salt are recommended.
