Vitamin and Mineral Supplements for Age-Related Macular Degeneration
Q. Why were you asked to read this handout?
Q. What were the supplements used in the AREDS study?
Q. How was the study performed?
Q. What was studied?
Q. What were the results?
Q. What if I already have advanced AMD?
Q. What if I can’t tolerate all of the supplements?
Q. What are the side effects of high doses of antioxidants and zinc?
Q. Should all patients with AMD take supplements?
Q. Who should not take the supplements?
Q. Can I eat fruits and vegetables containing beta-carotene if I smoke?
Q. Should I take lutein and zeaxanthin?
Q. Should people without AMD take supplements?
Q. Why were you asked to read this handout?
The Age-Related Eye Disease Study (AREDS) results were reported in October 2002. This 10-year study was sponsored by the National Eye Institute (NEI) demonstrated that large doses of antioxidants and zinc could prevent vision loss from AMD.
Q. What were the supplements used in the AREDS study?
The antioxidants used in the study were vitamin C, vitamin E and beta-carotene. The minerals used in the study were zinc and copper. Daily doses taken by patients in the study are listed below. These doses are much higher than the recommended daily allowances (RDA) from the U.S. Food and Drug Administration. The doses in the multi-vitamin Centrum Silver also are listed for comparison. The majority, 67 percent, of the patients in the study were also taking Centrum Silver.
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Vitamin
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Age-Related Eye Disease Study Doses
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RDA (recommended daily allowances) range for males and females
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Centrum Silver
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Vitamin C (ascorbic acid)
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500 mg
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60-90 mg
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60 mg
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Vitamin E
(dl-alpha tocopheryl acetate)
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400 IU
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22 IU (15 mg)
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45 IU
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Beta-carotene
( Pro-vitamin A)
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15 mg (25,000 IU)
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2333-3000 IU (700 to 900 g) Vitamin A
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5000 IU vitamin A (20% as beta-carotene)
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Zinc (zinc oxide)
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80 mg
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15 mg
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15 mg
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Copper (cupric oxide)*
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2 mg
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2 mg
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2 mg
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* Copper was taken with zinc to prevent anemia (low blood count)
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Q. How was the study performed?
The study followed 3,640 patients ages 55 to 80 who had AMD. The patients were randomly assigned to receive daily tablets from one of these four groups:
- Antioxidants only (vitamin C, vitamin E, beta-carotene)
- Zinc and copper
- Antioxidants plus zinc and copper
- Placebo (nothing, i.e., “sugar pills”)
The patients were then followed by vision testing, dilated eye examinations and ophthalmic photography every six months.
Q. What was studied?
Scientists looked for decreases in vision and development of advanced AMD. Advanced AMD was defined as development of wet macular degeneration (abnormal blood vessel growth with leakage of fluid and bleeding under the retina), or death of the retina (geographic atrophy) involving the central vision. Advanced AMD typically leads to vision loss.
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Q. What were the results?
The study showed that patients who took antioxidants and zinc had less vision loss and were less likely to develop advanced AMD that the other three groups. Patients taking antioxidants and zinc were 20 percent less likely to experience vision loss compared to patients taking placebo, and 25 percent less likely to develop advanced AMD. Only patients with a certain level of early AMD benefited.
Q. What if I already have advanced AMD?
Patients with advanced or late AMD in one eye benefited the most in preventing vision loss in their good eye. Also, antioxidants and zinc reduced further vision loss in the eye with advanced AMD.
Q. What if I can’t tolerate all of the supplements?
The study showed that there is a significant benefit to taking zinc and copper alone. There was less benefit when taking the antioxidants alone. Treatment with zinc alone or antioxidants alone reduced loss of vision, but it was not as beneficial as treatment with zinc and antioxidants in combination.
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Q. What are the side effects of high doses of antioxidants and zinc?
The study carefully documented adverse effects that could have been caused by antioxidant and zinc supplements. There was no increased risk of death, heart problems or anemia (low blood count). There was a slight increase in genitourinary tract infections in both men and women taking zinc (either alone or with antioxidants): 7.5 percent of patients receiving zinc versus 4.9 percent patients not receiving zinc were hospitalized for genitourinary problems. Some patients receiving antioxidants noted yellowing of the skin.
Q. Should all patients with AMD take supplements?
The supplements only benefited patients with enough retinal changes to be at risk for advanced AMD. The supplements did not prevent the accumulation of the early changes of macular degeneration (e.g., the yellow spots under the retina called drusen and pigment changes). An ophthalmologist (a medical doctor specializing in the eyes) can determine if you should take the supplements. UT Southwestern recommends that everyone 55 years of age or older be examined by an ophthalmologist to determine if they have AMD and if they should take the supplements.
Q. Who should not take the supplements?
Current smokers who take beta-carotene (vitamin A) are more likely to develop lung cancer and die. People who smoke should not take beta-carotene. Further study is needed to determine if former smokers are at increased risk for death from beta-carotene. For now, we recommend that former smokers consider taking beta-carotene only if they have not smoked for several years (preferably 15 years) and have advanced AMD in one eye.
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Q. Can I eat fruits and vegetables containing beta-carotene if I smoke?
Yes. Eating foods rich in beta-carotene is associated with a reduced risk of death and cancer from smoking. One medium sized carrot contains 5 mg of beta-carotene and other green and yellow vegetables such as spinach are good sources of vitamin A, lutein, and zeaxanthin.
Q. Should I take lutein and zeaxanthin?
Lutein and zeaxanthin (L+Z) are concentrated in the central macula, the part of the eye used for fine vision and which is affected by AMD. L+Z are referred to as macular pigments. These are thought to protect the retina from blue light damage. We know that L+Z in the macula decreases with age. We also know that dietary supplements can increase macular pigment levels. We do not yet know if such supplements benefit AMD patients.
Q. Should people without AMD take supplements?
At this time there is no evidence that supplements prevent or retard the development of the early symptoms of AMD. Family members of AMD patients are at increased risk of developing the disease and should have a dilated eye exam by age 50 to look for early signs of AMD.
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