Vitamin Supplement Use May Reduce Effects of Alzheimer’s Disease
Antioxidant vitamin supplements, particularly vitamins E and C, may protect the aging brain against damage associated with the pathological changes of Alzheimer’s disease, according to a study conducted by the Johns Hopkins Bloomberg School of Public Health and other institutions. The researchers believe antioxidant vitamin supplements may be an ideal prevention strategy for our aging population as they are relatively nontoxic and are thought to have wide-ranging health benefits. The study, “Reduced Risk of Alzheimer’s Disease in Users of Antioxidant Vitamin Supplements” is published in the January 2004, issue of the journal Archives of Neurology.
Peter P. Zandi, PhD, lead author of the study and an assistant professor in the School’s Department of Mental Health, said, “These results are extremely exciting. Our study suggests that the regular use of vitamin E in nutritional supplement doses, especially in combination with vitamin C, may reduce the risk of developing Alzheimer's disease.”
The researchers examined data from the Cache County Study, which is a large, population-based investigation of the prevalence and incidence of Alzheimer’s disease and other dementias. Residents who were 65 or older were assessed from 1996-1997 and again from 1998-2000. Study participants were asked at their first contact about vitamin usage. The researchers then compared the subsequent risk of developing Alzheimer’s disease over the study interval among supplement users versus nonusers to come to their conclusions.
Approximately 17 percent of the study participants reported taking vitamin E or C supplements. These individuals were significantly more likely to be female, younger, better educated and reported better general health when compared to non-supplement users. In addition to those who took vitamin supplements, another 20 percent of study participants used multivitamins, but without a high dosage of vitamin E or C.
The researchers found a trend towards reduced Alzheimer’s disease with a combination of vitamin E and C supplements, even after controlling for age, sex, education and general health. However, there was no notable reduction in the risk of Alzheimer’s disease with vitamin E or vitamin C alone or with multivitamins. Multivitamins typically contain the recommended daily allowance of vitamin E (22 IU or 15 mg) and vitamin C (75-90 mg), while individual supplements contain doses up to 1,000 IU of vitamin E and 500-1,000 mg or more of vitamin C.
The researchers explained that the use of vitamins E and C may offer protection against Alzheimer’s disease when taken together in the higher doses available in individual supplements. In addition, there may be some protective effect with vitamin E when it is combined with the lower doses of vitamin C found in multivitamins.
Dr. Zandi said, “Further study with randomized prevention trials is needed before drawing firm conclusions about the protective effects of these antioxidants. Such trials should consider testing a regimen of vitamin E and C in combination. If effective, the use of these antioxidant vitamins may offer an attractive strategy for the prevention of Alzheimer's disease.”
The study was funded by grants from the National Institutes of Health and National Institute of Mental Health. The Bryan Alzheimer’s Disease Center at Duke University completed the APOE genotyping.
James C. Anthony, Ara S. Khachaturian, Stephanie V. Stone, Deborah Gustafson, JoAnn T. Tschanz, Maria C. Norton and John C. S. Breitner co-authored the study.Public Affairs Media Contacts for the Johns Hopkins Bloomberg School of Public Health: Kenna Brigham or Tim Parsons at 410-955-6878 or firstname.lastname@example.org. Photographs of Peter Zandi are available upon request.