Prevention of Blindness Society...
DECEMBER 2001
The Effect of Nutritional Supplements on Age-Related Macular Degeneration and Cataract
Prevention of Blindness Society...DECEMBER 2001
The Effect of Nutritional Supplements on Age-Related Macular Degeneration and Cataract
On Saturday, November 17, Emily Chew, M.D., an investigator
with the National Eye Institute, addressed a large audience at Sibley Memorial
Hospital for the Society’s Annual Meeting.
The group had gathered to learn about the results of the
Age-Related Eye Disease Study (AREDS), a major clinical trial sponsored by the
National Eye Institute. Dr. Chew
indicated that a dietary supplement with high levels of antioxidants and zinc
significantly reduces the risk of advanced age-related macular degeneration
(AMD) by about 25 percent. These
same supplements also reduce the risk of vision loss caused by advanced AMD by
about 19 percent. They have no
significant effect on the development or progression of cataracts. 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.
Based on the findings of the study, people who are at high
risk for developing advanced AMD should consider taking the supplements. Your eye care professional can tell you
if you have AMD and if you are at risk for developing the advanced form of the
disease. If you are already taking
daily multivitamins and your doctor suggests you take the dietary supplements
used in the AREDS, review all the supplements with your doctor.
The specific daily amounts of antioxidants and minerals used
by the study were 500 milligrams of vitamin C; 400 International Units of
vitamin E; 15 milligrams of beta-carotene; 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, which may be associated with high levels of zinc
supplementation.
The 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.
Participants that took zinc also reported anemia at a slightly higher
rate; however, testing of all patients for this disorder showed no difference
among treatment groups. Yellowing
of the skin, a well-known side effect of large doses of beta-carotene, was
reported slightly more often by participants taking antioxidants.
An eye care company that was a collaborator in the AREDS and
provided the study supplements, currently markets the formulation that was used
in the study. Other companies will
probably provide similar formulations.
Antioxidant and zinc supplements can also be purchased separately;
however consumers should discuss the use of these high levels of supplements
with their doctors, and be certain to include copper whenever taking high
levels of zinc.
Source: “The Effect of Nutritional
Supplements on Age-Related Macular Degeneration and Cataract - Results of the
Age-Related Eye Disease Study,” National Eye Institute, National Institutes of
Health
© 2001 Prevention of Blindness Society of the Metropolitan Area, Washington, DC. All Rights Reserved.