MedicalResearch.com Interview with:
Richard J. Kryscio, Ph.D.
Statistics and Chair, Biostatistics and Sanders-Brown Center on Aging
Sanders-Brown Center on Aging
University of Kentucky
MedicalResearch.com: What is the background for this study?
Response: At the time the trial was initiated (2002), there was ample evidence that oxidative stress is an important mechanism in brain aging. Research showed that protein oxidation is linked to the brain’s response to the abnormal proteins seen in Alzheimer disease (amyloid beta plaques in particular) leading to inflammation, DNA repair problems, reduced energy production, and other cellular changes that are identified mechanisms in the Alzheimer brain.
Both vitamin E and selenium are antioxidants. Antioxidants, either through food or supplements, are believed to reduce oxidative stress throughout the body. In the brain, they may reduce the formation of amyloid beta plaques, reduce brain inflammation, and improve other brain processes. Studies in humans support these hypotheses. The Rotterdam study in the Netherlands, as an example, showed that initial blood levels of vitamin E could predict dementia risk. Those people with higher vitamin E levels were 25% less likely to develop dementia. Also, selenium deficiency results in cognitive difficulties and several population-based studies have shown an association between selenium level and cognitive decline (lower selenium levels are linked to thinking changes in the elderly).