The AREDS Formulation and Age-Related Macular Degeneration
Are These High Levels of Antioxidants and Zinc Right For You?
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.
But is the AREDS formulation right for you? Here are some questions and answers that can help you make that decision.
On this page:
- Who Should Take the AREDS Formulation?
- What is the Dosage of the AREDS Formulation?
- Can I Take a Daily Multivitamin if I Am Taking the AREDS Formulation?
- Can a Daily Multivitamin Alone Provide the Same High Levels of Antioxidants and Zinc as the AREDS Formulation?
- Can Diet Alone Provide the Same High Levels of Antioxidants and Zinc as the AREDS Formulation?
- Will Taking the AREDS Formulation Prevent Me from Developing AMD?
- Are There Any Side Effects from the AREDS Formulation?
- Are Former Smokers at an Increased Risk for Developing Lung Cancer if They Take High Doses of Beta-Carotene?
- Should Young People with Inherited Macular Degeneration Take the AREDS Formulation?
- Will taking high dose vitamin E in the AREDS formulation increase my risk of prostate cancer?
Who Should Take the AREDS Formulation?
People who are at high risk for developing advanced AMD should consider taking the combination of nutrients used in the study. Your eye care professional can tell you if you have AMD and are at risk for developing the advanced form of the disease. The doctor should give you a dilated eye exam in which drops are placed in your eyes. This allows for a careful examination of the inside of the eye to look for signs of AMD.
Before taking these high levels of vitamins and minerals, you should talk with your doctor about the risk of developing advanced AMD and whether taking the AREDS formulation is right for you.
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; and two 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.
If you are already taking daily multivitamins and your doctor suggests you take the AREDS formulation, be sure to review all your vitamins with your doctor before you begin.
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 Me 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.
Are There Any Side Effects from the AREDS Formulation?
Some AREDS participants reported minor side effects from the treatments. About 7.5 percent of participants assigned to the zinc treatments - compared with five percent who did not have zinc in their assigned treatment - had urinary tract problems that required hospitalization. Yellowing of the skin, a well-known side effect of large doses of beta-carotene, was reported slightly more often by participants taking antioxidants.
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.
In deciding whether to include beta-carotene in a formulation designed to slow the development of advanced AMD, you and your doctor should balance the apparent increase in the risk of lung cancer associated with beta-carotene with the risk of AMD progression.
Should Young People with Inherited Macular Degeneration Take the AREDS Formulation?
The AREDS only studied age-related macular degeneration. We have no recommendations for younger people with the inherited (juvenile) forms of macular degeneration.
Will taking high dose vitamin E in the AREDS formulation increase my risk of prostate cancer?
The long-term follow-up from The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was published in October 16, 2011 edition of The Journal of the American Medical Association. The study found that taking high dose vitamin E supplements (400 IUs daily) significantly increased the risk of prostate cancer among healthy men when compared with healthy men taking a placebo (a sugar pill). The researchers found that the increased risk means that there will be 1 to 2 more prostate cancers per 1000 patients who took the high dose vitamin E for one year. Interestingly, in men who received both vitamin E and selenium, there was no increased rate of prostate cancer.
These findings from SELECT should be reviewed in the context of prior clinical trials results. Men participating in the Alpha-Tocopherol, Beta Carotene (ATBC) trial who took 50 mg of vitamin E daily had a 35 percent reduction in the risk of prostate cancer. The Physicians Health Study II (PHS II) tested 400 IUs of vitamin E every other day and found no effect on the incident of prostate cancer.
The daily dose of vitamin E in SELECT is the same as in the Age-Related Eye Disease Study (AREDS) formulation (400 IUs daily). However, AREDS study participants who received vitamin E also received other antioxidants (vitamin C and beta carotene with or without zinc). NEI researchers have conducted an analysis of the AREDS data. The AREDS formulation did not have an effect on the rate of prostate cancer in men participating in the study.
The AREDS formulation is given also in the Age-Related Eye Disease Study 2 (AREDS2), a study that is designed to test other supplements, lutein and zeaxanthin and the omega-3 fatty acids, DHA and EPA for the treatment of age-related macular degeneration. The group of independent researchers who monitors the current AREDS2 for safety has not noted any concerns in increased risk prostate cancer. All the AREDS2 study participants will be continuing to take the AREDS formulation that contains vitamin E in this study.
Although the SELECT study has demonstrated a slight increase in prostate cancer with supplementation with vitamin E, it is important to understand that not all clinical trials have found the same results. You are encouraged to speak with your health care professional about these results and your risk for vision loss or prostate cancer.
Revised November 2011