Age-Related Macular Degeneration (AMD)
What is age-related macular degeneration?
Age-related macular degeneration (AMD) is a disease associated with aging that gradually destroys sharp, central vision. Central vision is needed for seeing objects clearly and for common daily tasks such as reading and driving. AMD affects the macula, the part of the eye that allows you to see fine detail. AMD causes no pain.
In some cases, AMD advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes. AMD is a leading cause of vision loss in Americans 60 years of age and older. AMD occurs in two forms: wet and dry.
The Age-Related Eye Disease Study (AREDS) – sponsored by the Federal government’s National Eye Institute – has found that taking high levels of antioxidants and zinc can reduce the risk of developing advanced age-related macular degeneration (AMD) by about 25 percent.
This major clinical trial closely followed about 3,600 participants with varying stages of AMD. The results showed that the AREDS formulation, while not a cure for AMD, may play a key role in helping people at high risk for developing advanced AMD keep their remaining vision.
What is the Dosage of the AREDS Formulation?
The specific daily amounts of antioxidants and zinc used by the study researchers were: 500 milligrams of vitamin C
400 International Units of vitamin E
15 milligrams of beta-carotene (often labeled as equivalent to 25,000 International Units of vitamin A)
80 milligrams of zinc as zinc oxide
2 milligrams of copper as cupric oxide (Copper was added to the AREDS formulations containing zinc to prevent copper deficiency anemia, a condition associated with high levels of zinc intake.)
Can I Take a Daily Multivitamin if I Am Taking the AREDS Formulation?
Yes. A daily multivitamin contains many important nutrients not found in the AREDS formulation. For example, elderly people with osteoporosis need to be particularly concerned about taking vitamin D, which is not in the AREDS formulation. The AREDS formulation is not a substitute for a multivitamin. In the Age-Related Eye Disease Study, two-thirds of the study participants took multivitamins along with the AREDS formulation.
Can a Daily Multivitamin Alone Provide the Same High Levels of Antioxidants and Zinc as the AREDS Formulation?
No. The AREDS formulation’s levels of antioxidants and zinc are considerably higher than the amounts in any daily multivitamin.
Can Diet Alone Provide the Same High Levels of Antioxidants and Zinc as the AREDS Formulation?
No. The high levels of vitamins and minerals are difficult to achieve from diet alone. However, previous studies have suggested that people who have diets rich in green, leafy vegetables have a lower risk of developing AMD.
Will Taking the AREDS Formulation Prevent a Person from Developing AMD?
No. There is no known treatment that can prevent the development of AMD. The study did not show that the AREDS formulation prevented people from developing early signs of AMD. No recommendation has been made for taking the AREDS formulation to prevent early AMD.
Taking the formulation reduced the rate of advanced AMD in people at high risk by about 25 percent over a 6-year period. We do not know if this treatment effect will persist over a longer period. However, by continuing to follow the AREDS participants, we hope to find out if the treatment effect will last longer than six years.
Where Can I Buy the AREDS Formulation?
You can purchase the AREDS formulation at drug stores, supermarkets, health food stores, and other retail outlets that sell pharmaceutical products. The vitamins and minerals can also be purchased separately; be certain to include copper whenever taking high levels of zinc. Taking beta-carotene is not recommended for smokers.
Are Former Smokers at an Increased Risk for Developing Lung Cancer if They Take High Doses of Beta-Carotene?
Large clinical trials sponsored by the National Cancer Institute demonstrated that beta-carotene increases the risk of lung cancer in current smokers. In these trials, most of these smokers were heavy smokers. The only other large clinical trial evaluating beta-carotene was the Physicians Health Study (PHS). In the PHS, there was no evidence of increased cancer risk in those randomly assigned to beta-carotene, but few physicians were active smokers. There also was no evidence of an increased risk of lung cancer in former smokers. However, many studies suggest that former smokers maintain some increased risk of lung cancer for years after stopping smoking. Therefore, it is reasonable to expect that beta-carotene may also slightly increase their risk of cancer, at least for a period of several years.
Omega-3 Fatty Acids Protect Eyes Against Retinopathy
Omega-3 polyunsaturated fatty acids (found in fish oil, flaxseed) protect against the development and progression of retinopathy, a deterioration of the retina, in mice.
The researchers found that increasing omega-3 fatty acids and decreasing omega-6 fatty acids in the diet reduced the area of vessel loss that ultimately causes the growth of the abnormal vessels and blindness. Omega-6 fatty acid contributes to the growth of abnormal blood vessels in the retina.
Information obtained from the National Eye Institute Website: www.nei.nih.gov